TY - JOUR ID - 195 TI - Combinatorial biosynthesis in yeast leads to over 200 diterpenoids JO - Metab. Eng. PY - 2024 SP - 193-200 AU - Frey, M. AU - Bathe, U. AU - Meink, L. AU - Balcke, G. U. AU - Schmidt, J. AU - Frolov, A. AU - Soboleva, A. AU - Hassanin, A. AU - Davari, M. D. AU - Frank, O. AU - Schlagbauer, V. AU - Dawid, C. AU - Tissier, A. AU - VL - 82 UR - https://doi.org/10.1016/j.ymben.2024.02.006 DO - 10.1016/j.ymben.2024.02.006 AB - Diterpenoids form a diverse group of natural products, many of which are or could become pharmaceuticals or industrial chemicals. The modular character of diterpene biosynthesis and the promiscuity of the enzymes involved make combinatorial biosynthesis a promising approach to generate libraries of diverse diterpenoids. Here, we report on the combinatorial assembly in yeast of ten diterpene synthases producing (+)-copalyldiphosphate-derived backbones and four cytochrome P450 oxygenases (CYPs) in diverse combinations. This resulted in the production of over 200 diterpenoids. Based on literature and chemical database searches, 162 of these compounds can be considered new-to-Nature. The CYPs accepted most substrates they were given but remained regioselective with few exceptions. Our results provide the basis for the systematic exploration of the diterpenoid chemical space in yeast using sequence databases. A2 - C1 - Bioorganic Chemistry; Cell and Metabolic Biology ER - TY - JOUR ID - 193 TI - Sydnone imines as a new class of promising plant growth and stress tolerance modulators—A first experimental structure–activity overview JO - Stresses PY - 2024 SP - 133-154 AU - Cherevatskaya, M. AU - Cherepanov, I. AU - Kalganova, N. AU - Erofeeva, N. AU - Romanovskaya, E. AU - Frolov, A. AU - Bilova, T. AU - Moiseev, S. AU - Wessjohann, L. A. AU - VL - 4 UR - https://doi.org/10.3390/stresses4010008 DO - 10.3390/stresses4010008 AB - Due to the oncoming climate changes, various environmental stresses (drought, salinity, heavy-metals, low or high temperatures, etc.) might dramatically affect crop yields and the quality of produced foods. Therefore, to meet the growing food demand of the human population, improvement of stress tolerance of the currently cultured crops is required. The knowledge of the molecular underlying mechanisms provides a versatile instrument to correct plant metabolism via chemical tools and to thereby increase their adaptive potential. This will preserve crop productivity and quality under abiotic stress conditions. Endogenously produced nitric oxide (NO) is one of the key signaling factors activating stress tolerance mechanisms in plants. Thus, the application of synthetic NO donors as stress-protective phytoeffectors might support maintaining plant growth and productivity under stressful conditions. Sydnone imines (sydnonimines) are a class of clinically established mesoionic heterocyclic NO donors which represent a promising candidate group for such phytoeffectors. Therefore, here, we provide an overview of the current progress in the application of sydnone imines as exogenous NO donors in plants, with a special emphasis on their potential as herbicides as well as herbicide antidotes, growth stimulants and stress protectors triggering plant tolerance mechanisms. We specifically address the structure–activity relationships in the context of the growth modulating activity of sydnone imines. Growth stimulating or antidote effects are typical for 4-α-hydroxybenzyl derivatives of sydnone imines containing an alkyl substituent in position N-3. The nature of the substituent of the N-6 atom has a significant influence on the activity profile and the intensity of the effect. Nevertheless, further investigations are necessary to establish reliable structure–activity relationships (SAR). Consequently, sydnone imines might be considered promising phytoeffector candidates, which are expected to exert either protective effects on plants growing under unfavorable conditions, or herbicidal ones, depending on the exact structure. A2 - C1 - Bioorganic Chemistry ER - TY - INPR ID - 2490 TI - Maximizing the value of indole-3-carbinol, from its distribution in dietary sources, health effects, metabolism, extraction, and analysis in food and biofluids JO - Crit. Rev. Food Sci. Nutr. PY - 2023 SP - 1-22 AU - Nagia, M. AU - Morgan, I. AU - Gamel, M. A. AU - Farag, M. A. AU - VL - UR - https://doi.org/10.1080/10408398.2023.2197065 DO - 10.1080/10408398.2023.2197065 AB - Indole-3-carbinol (I3C) is a major dietary component produced in Brassica vegetables from glucosinolates (GLS) upon herbivores’ attack. The compound is gaining increasing interest due to its anticancer activity. However, reports about improving its level in plants or other sources are still rare. Unfortunately, I3C is unstable in acidic media and tends to polymerize rendering its extraction and detection challenging. This review presents a multifaceted overview of I3C regarding its natural occurrence, biosynthesis, isolation, and extraction procedure from dietary sources, and optimization for the best recovery yield. Further, an overview is presented on its metabolism and biotransformation inside the body to account for its health benefits and factors to ensure the best metabolic yield. Compile of the different analytical approaches for I3C analysis in dietary sources is presented for the first time, together with approaches for its detection and its metabolism in body fluids for proof of efficacy. Lastly, the chemopreventive effects of I3C and the underlying action mechanisms are summarized. Optimizing the yield and methods for the detection of I3C will assist for its incorporation as a nutraceutical or adjuvant in cancer treatment programs. Highlighting the complete biosynthetic pathway and factors involved in I3C production will aid for its future biotechnological production. A2 - C1 - Bioorganic Chemistry ER - TY - JOUR ID - 287 TI - Averrhoa carambola L. fruit and stem metabolites profiling and immunostimulatory action mechanisms against cyclosporine induced toxic effects in rat model as analyzed using UHPLC/MS-MS-based chemometrics and bioassays JO - Food Chem. Toxicol. PY - 2023 SP - 114001 AU - S. Ramadan, N. AU - Fayek, N. M. AU - M. El-Sayed, M. AU - S. Mohamed, R. AU - Wessjohann, L. A. AU - Farag, M. A. AU - VL - 179 UR - https://doi.org/10.1016/j.fct.2023.114001 DO - 10.1016/j.fct.2023.114001 AB - The Averrhoa carambola L. tree encompasses a myriad of phytochemicals contributing to its nutritional and health benefits. The current study aims at investigating the A. carambola L. the metabolite profile grown in tropical and temperate regions represented by fruit and stem, for the first time using UPLC/MS-based molecular networking and chemometrics. Asides, assessment of the immunostimulatory effect of ripe fruit and stem, was compared in relation to metabolite fingerprints. Eighty metabolites were identified, 8 of which are first-time to be reported including 3 dihydrochalcone-C-glycosides, 4 flavonoids, and one phenolic. Multivariate data analysis revealed dihydrochalcones as origin-discriminating metabolites between temperate and tropical grown fruits. Further, an in vivo immunomodulatory assay in a cyclosporine A-induced rat model revealed a potential immune-enhancing effect as manifested by down-regulation of inflammatory markers (IL-6, INF-γ, IL-1, TLR4, and ESR) concurrent with the up-regulation of CD4 level and the CD4/CD8 ratio. Moreover, both extracts suppressed elevation of liver and kidney functions in serum as well as reduction in oxidative stress with concurrent increased levels of T-protein, albumin, globulin, and A/G ratio. This study pinpoints differences in secondary metabolite profiles amongst A. carambola L. accessions from different origins and organ type and its immunomodulatory action mechanisms. A2 - C1 - Bioorganic Chemistry ER - TY - JOUR ID - 285 TI - Identification and characterization of three new antimicrobial peptides from the marine mollusk Nerita versicolor (Gmelin, 1791) JO - Int. J. Mol. Sci. PY - 2023 SP - 3852 AU - Rodriguez, A. AU - Martell-Huguet, E. M. AU - González-García, M. AU - Alpízar-Pedraza, D. AU - Alba, A. AU - Vazquez, A. A. AU - Grieshober, M. AU - Spellerberg, B. AU - Stenger, S. AU - Münch, J. AU - Kissmann, A.-K. AU - Rosenau, F. AU - Wessjohann, L. A. AU - Wiese, S. AU - Ständker, L. AU - Otero-González, A. J. AU - VL - 24 UR - https://doi.org/10.3390/ijms24043852 DO - 10.3390/ijms24043852 AB - Mollusks have been widely investigated for antimicrobial peptides because their humoral defense against pathogens is mainly based on these small biomolecules. In this report, we describe the identification of three novel antimicrobial peptides from the marine mollusk Nerita versicolor. A pool of N. versicolor peptides was analyzed with nanoLC-ESI-MS-MS technology, and three potential antimicrobial peptides (Nv-p1, Nv-p2 and Nv-p3) were identified with bioinformatical predictions and selected for chemical synthesis and evaluation of their biological activity. Database searches showed that two of them show partial identity to histone H4 peptide fragments from other invertebrate species. Structural predictions revealed that they all adopt a random coil structure even when placed near a lipid bilayer patch. Nv-p1, Nv-p2 and Nv-p3 exhibited activity against Pseudomonas aeruginosa. The most active peptide was Nv-p3 with an inhibitory activity starting at 1.5 µg/mL in the radial diffusion assays. The peptides were ineffective against Klebsiella pneumoniae, Listeria monocytogenes and Mycobacterium tuberculosis. On the other hand, these peptides demonstrated effective antibiofilm action against Candida albicans, Candida parapsilosis and Candida auris but not against the planktonic cells. None of the peptides had significant toxicity on primary human macrophages and fetal lung fibroblasts at effective antimicrobial concentrations. Our results indicate that N. versicolor-derived peptides represent new AMP sequences and have the potential to be optimized and developed into antibiotic alternatives against bacterial and fungal infections. A2 - C1 - Bioorganic Chemistry ER - TY - JOUR ID - 281 TI - Correction to: Simple and robust multiple shoot regeneration and root induction cycle from different explants of Hypericum perforatum L. genotypes JO - Plant Cell Tiss. Organ Cult. PY - 2023 SP - 19 AU - Ravindran, B. M. AU - Rizzo, P. AU - Franke, K. AU - Fuchs, J. AU - D’Auria, J. AU - VL - 152 UR - https://doi.org/10.1007/s11240-022-02418-x DO - 10.1007/s11240-022-02418-x AB - A2 - C1 - Bioorganic Chemistry ER - TY - JOUR ID - 223 TI - Prenylated isoflavanones with antimicrobial potential from the root bark of Dalbergia melanoxylon JO - Metabolites PY - 2023 SP - 678 AU - Chalo, D. M. AU - Franke, K. AU - Nchiozem-Ngnitedem, V.-A. AU - Kakudidi, E. AU - Origa-Oryem, H. AU - Namukobe, J. AU - Kloss, F. AU - Yenesew, A. AU - Wessjohann, L. A. AU - VL - 13 UR - https://doi.org/10.3390/metabo13060678 DO - 10.3390/metabo13060678 AB - Dalbergia melanoxylon Guill. & Perr (Fabaceae) is widely utilized in the traditional medicine of East Africa, showing effects against a variety of ailments including microbial infections. Phytochemical investigation of the root bark led to the isolation of six previously undescribed prenylated isoflavanones together with eight known secondary metabolites comprising isoflavanoids, neoflavones and an alkyl hydroxylcinnamate. Structures were elucidated based on HR-ESI-MS, 1- and 2-D NMR and ECD spectra. The crude extract and the isolated compounds of D. melanoxylon were tested for their antibacterial, antifungal, anthelmintic and cytotoxic properties, applying established model organisms non-pathogenic to humans. The crude extract exhibited significant antibacterial activity against Gram-positive Bacillus subtilis (97% inhibition at 50 μg/mL) and antifungal activity against the phytopathogens Phytophthora infestans, Botrytis cinerea and Septoria tritici (96, 89 and 73% at 125 μg/mL, respectively). Among the pure compounds tested, kenusanone H and (3R)-tomentosanol B exhibited, in a panel of partially human pathogenic bacteria and fungi, promising antibacterial activity against Gram-positive bacteria including methicillin-resistant Staphylococcus aureus (MRSA) and Mycobacterium showing MIC values between 0.8 and 6.2 μg/mL. The observed biological effects support the traditional use of D. melanoxylon and warrant detailed investigations of its prenylated isoflavanones as antibacterial lead compounds. A2 - C1 - Bioorganic Chemistry ER - TY - JOUR ID - 217 TI - Characterization and bioactive potential of secondary metabolites isolated from Piper sarmentosum Roxb. JO - Int. J. Mol. Sci. PY - 2023 SP - 1328 AU - Bin Ware, I. AU - Franke, K. AU - Dube, M. AU - Ali El Enshasy, H. AU - Wessjohann, L. A. AU - VL - 24 UR - https://doi.org/10.3390/ijms24021328 DO - 10.3390/ijms24021328 AB - Piper sarmentosum Roxb. (Piperaceae) is a traditional medicinal plant in South-East Asian countries. The chemical investigation of leaves from this species resulted in the isolation of three previously not described compounds, namely 4″-(3-hydroxy-3-methylglutaroyl)-2″-β-D-glucopyranosyl vitexin (1), kadukoside (2), and 6-O-trans-p-coumaroyl-D-glucono-1,4-lactone (3), together with 31 known compounds. Of these known compounds, 21 compounds were isolated for the first time from P. sarmentosum. The structures were established by 1D and 2D NMR techniques and HR-ESI-MS analyses. The compounds were evaluated for their anthelmintic (Caenorhabditis elegans), antifungal (Botrytis cinerea, Septoria tritici and Phytophthora infestans), antibacterial (Aliivibrio fischeri) and cytotoxic (PC-3 and HT-29 human cancer cells lines) activities. Methyl-3-(4-methoxyphenyl)propionate (8), isoasarone (12), and trans-asarone (15) demonstrated anthelmintic activity with IC50 values between 0.9 and 2.04 mM. Kadukoside (2) was most active against S. tritici with IC50 at 5.0 µM and also induced 94% inhibition of P. infestans growth at 125 µM. Trans-asarone (15), piperolactam A (23), and dehydroformouregine (24) displayed a dose-dependent effect against B. cinerea from 1.5 to 125 µM up to more than 80% inhibition. Paprazine (19), cepharadione A (21) and piperolactam A (23) inhibited bacterial growth by more than 85% at 100 µM. Only mild cytotoxic effects were observed. A2 - C1 - Bioorganic Chemistry ER - TY - JOUR ID - 209 TI - Dissection of Moringa oleifera leaf metabolome in context of its different extracts, origin and in relationship to its biological effects as analysed using molecular networking and chemometrics JO - Food Chem. PY - 2023 SP - 133948 AU - Abdel Shakour, Z. T. AU - El-Akad, R. H. AU - Elshamy, A. I. AU - El Gendy, A. E.-N. G. AU - Wessjohann, L. A. AU - Farag, M. A. AU - VL - 399 UR - https://doi.org/10.1016/j.foodchem.2022.133948 DO - 10.1016/j.foodchem.2022.133948 AB - M. oleifera known as “miracle tree” is increasingly used in nutraceuticals for the reported health effects and nutritional value of its leaves. This study presents the first metabolome profiling of M. oleifera leaves of African origin using different solvent polarities via HR-UPLC/MS based molecular networking followed by multivariate data analyses for samples classification. 119 Chemicals were characterized in both positive and negative modes belonging to 8 classes viz. phenolic acids, flavonoids, peptides, fatty acids/amides, sulfolipids, glucosinolates and carotenoids. New metabolites i.e., polyphenolics, fatty acids, in addition to a new class of sulfolipids were annotated for the first time in Moringa leaves. In vitro anti-inflammatory and anti-aging bioassays of the leaf extracts were assessed and in correlation to their metabolite profile via multivariate data analyses. Kaempferol, quercetin and apigenin-O/C-glycosides, fatty acyl amides and carotenoids appeared crucial for biological activities and leaves origin discrimination. A2 - C1 - Bioorganic Chemistry ER - TY - JOUR ID - 264 TI - Indonesian marine and its medicinal contribution JO - Natural Products and Bioprospecting PY - 2023 SP - 38 AU - Nugraha, A. S. AU - Firli, L. N. AU - Rani, D. M. AU - Hidayatiningsih, A. AU - Lestari, N. D. AU - Wongso, H. AU - Tarman, K. AU - Rahaweman, A. C. AU - Manurung, J. AU - Ariantari, N. P. AU - Papu, A. AU - Putra, M. Y. AU - Pratama, A. N. W. AU - Wessjohann, L. A. AU - Keller, P. A. AU - VL - 13 UR - https://doi.org/10.1007/s13659-023-00403-1 DO - 10.1007/s13659-023-00403-1 AB - The archipelagic country of Indonesia is populated by the densest marine biodiversity in the world which has created strong global interest and is valued by both Indigenous and European settlements for different purposes. Nearly 1000 chemicals have been extracted and identified. In this review, a systematic data curation was employed to collate bioprospecting related manuscripts providing a comprehensive directory based on publications from 1988 to 2022. Findings with significant pharmacological activities are further discussed through a scoping data collection. This review discusses macroorganisms (Sponges, Ascidian, Gorgonians, Algae, Mangrove) and microorganism (Bacteria and Fungi) and highlights significant discoveries, including a potent microtubule stabilizer laulimalide from Hyattella sp., a prospective doxorubicin complement papuamine alkaloid from Neopetrosia cf exigua, potent antiplasmodial manzamine A from Acanthostrongylophora ingens, the highly potent anti trypanosomal manadoperoxide B from Plakortis cfr. Simplex, mRNA translation disrupter hippuristanol from Briareum sp, and the anti-HIV-1 (+)-8-hydroxymanzamine A isolated from Acanthostrongylophora sp. Further, some potent antibacterial extracts were also found from a limited biomass of bacteria cultures. Although there are currently no examples of commercial drugs from the Indonesian marine environment, this review shows the molecular diversity present and with the known understudied biodiversity, reveals great promise for future studies and outcomes. A2 - C1 - Bioorganic Chemistry ER - TY - JOUR ID - 251 TI - Purpurascenines A–C, azepino-indole alkaloids from Cortinarius purpurascens: Isolation, biosynthesis, and activity studies on the 5-HT2A receptor JO - J. Nat. Prod. PY - 2023 SP - 1373-1384 AU - Lam, Y. T. H. AU - Hoppe, J. AU - Dang, Q. N. AU - Porzel, A. AU - Soboleva, A. AU - Brandt, W. AU - Rennert, R. AU - Hussain, H. AU - Davari, M. D. AU - Wessjohann, L. AU - Arnold, N. AU - VL - 86 UR - https://doi.org/10.1021/acs.jnatprod.2c00716 DO - 10.1021/acs.jnatprod.2c00716 AB - Three previously undescribed azepino-indole alkaloids, named purpurascenines A−C (1−3), together with the new-to-nature 7-hydroxytryptophan (4) as well as two known compounds, adenosine (5) and riboflavin (6), were isolated from fruiting bodies of Cortinarius purpurascens Fr. (Cortinariaceae). The structures of 1−3 were elucidated based on spectroscopic analyses and ECD calculations. Furthermore, the biosynthesis of purpurascenine A (1) was investigated by in vivo experiments using 13C-labeled sodium pyruvate, alanine, and sodium acetate incubated with fruiting bodies of C. purpurascens. The incorporation of 13C into 1 was analyzed using 1D NMR and HRESIMS methods. With [3-13C]-pyruvate, a dramatic enrichment of 13C was observed, and hence a biosynthetic route via a direct Pictet−Spengler reaction between α-keto acids and 7-hydroxytryptophan (4) is suggested for the biosynthesis of purpurascenines A−C (1−3). Compound 1 exhibits no antiproliferative or cytotoxic effects against human prostate (PC-3), colorectal (HCT-116), and breast (MCF-7) cancer cells. An in silico docking study confirmed the hypothesis that purpurascenine A (1) could bind to the 5-HT2A serotonin receptor’s active site. A new functional 5-HT2A receptor activation assay showed no functional agonistic but some antagonistic effects of 1 against the 5-HT-dependent 5-HT2A activation and likely antagonistic effects on putative constitutive activity of the 5-HT2A receptor. A2 - C1 - Bioorganic Chemistry ER - TY - JOUR ID - 250 TI - Challenging structure elucidation of lumnitzeralactone, an ellagic acid derivative from the Mangrove Lumnitzera racemosa JO - Mar. Drugs PY - 2023 SP - 242 AU - Kappen, J. AU - Manurung, J. AU - Fuchs, T. AU - Vemulapalli, S. P. B. AU - Schmitz, L. M. AU - Frolov, A. AU - Agusta, A. AU - Muellner-Riehl, A. N. AU - Griesinger, C. AU - Franke, K. AU - Wessjohann, L. A. AU - VL - 21 UR - https://doi.org/10.3390/md21040242 DO - 10.3390/md21040242 AB - The previously undescribed natural product lumnitzeralactone (1), which represents a derivative of ellagic acid, was isolated from the anti-bacterial extract of the Indonesian mangrove species Lumnitzera racemosa Willd. The structure of lumnitzeralactone (1), a proton-deficient and highly challenging condensed aromatic ring system, was unambiguously elucidated by extensive spectroscopic analyses involving high-resolution mass spectrometry (HRMS), 1D 1H and 13C nuclear magnetic resonance spectroscopy (NMR), and 2D NMR (including 1,1-ADEQUATE and 1,n-ADEQUATE). Determination of the structure was supported by computer-assisted structure elucidation (CASE system applying ACD-SE), density functional theory (DFT) calculations, and a two-step chemical synthesis. Possible biosynthetic pathways involving mangrove-associated fungi have been suggested. A2 - C1 - Bioorganic Chemistry ER - TY - JOUR ID - 232 TI - Bichromonol, a dimeric coumarin with anti-HIV activity from the stem bark of Hypericum roeperianum JO - Nat. Prod. Res. PY - 2023 SP - 1947-1953 AU - Fobofou, S. A. T. AU - Franke, K. AU - Brandt, W. AU - Manzin, A. AU - Madeddu, S. AU - Serreli, G. AU - Sanna, G. AU - Wessjohann, L. A. AU - VL - 37 UR - https://doi.org/10.1080/14786419.2022.2110094 DO - 10.1080/14786419.2022.2110094 AB - Infectious diseases caused by viruses like HIV and SARS-COV-2 (COVID-19) pose serious public health threats. In search for new antiviral small molecules from chemically underexplored Hypericum species, a previously undescribed atropisomeric C8-C8’ linked dimeric coumarin named bichromonol (1) was isolated from the stem bark of Hypericum roeperianum. The structure was elucidated by MS data and NMR spectroscopy. The absolute configuration at the biaryl axis was determined by comparing the experimental ECD spectrum with those calculated for the respective atropisomers. Bichromonol was tested in cell-based assays for cytotoxicity against MT-4 (CC50 ¼ 54 mM) cells and anti-HIV activity in infected MT-4 cells. It exhibits significant activity at EC50 ¼ 6.6–12.0 mM against HIV-1 wild type and its clinically relevant mutant strains. Especially, against the resistant variants A17 and EFVR, bichromonol is more effective than the commercial drug nevirapine and might thus have potential to serve as a new anti-HIV lead. A2 - C1 - Bioorganic Chemistry ER - TY - JOUR ID - 231 TI - Comparison of Balanites aegyptiaca parts: metabolome providing insights into plant health benefits and valorization purposes as analyzed using multiplex GC-MS, LC-MS, NMR-based metabolomics, and molecular networking JO - RSC Adv. PY - 2023 SP - 21471-21493 AU - Farag, M. A. AU - Baky, M. H. AU - Morgan, I. AU - Khalifa, M. R. AU - Rennert, R. AU - Mohamed, O. G. AU - El-Sayed, M. M. AU - Porzel, A. AU - Wessjohann, L. A. AU - Ramadan, N. S. AU - VL - 13 UR - https://doi.org/10.1039/D3RA03141A DO - 10.1039/d3ra03141a AB - Balanites aegyptiaca (L.) Delile (Zygophyllaceae), also known as the desert date, is an edible fruit-producing tree popular for its nutritional and several health benefits. In this study, multi-targeted comparative metabolic profiling and fingerprinting approaches were conducted for the assessment of the nutrient primary and secondary metabolite heterogeneity in different parts, such as leaves, stems, seeds, unripe, and ripe fruits of B. aegyptiaca using nuclear magnetic resonance (NMR), ultra-performance liquid chromatography (UPLC-MS), and gas chromatography mass-spectrometry (GC-MS) based metabolomics coupled to multivariate analyses and in relation to its cytotoxic activities. NMR-based metabolomic study identified and quantified 15 major primary and secondary metabolites belonging to alkaloids, saponins, flavonoids, sugars, and amino and fatty acids. Principal component analysis (PCA) of the NMR dataset revealed α-glucose, sucrose, and isorhamnetin as markers for fruit and stem and unsaturated fatty acids for predominated seeds. Orthogonal projections to latent structure discriminant analysis (OPLS-DA) revealed trigonelline as a major distinctive metabolite in the immature fruit and isorhamnetin as a major distinct marker in the mature fruit. UPLC-MS/MS analysis using feature-based molecular networks revealed diverse chemical classes viz. steroidal saponins, N-containing metabolites, phenolics, fatty acids, and lipids as the constitutive metabolome in Balanites. Gas chromatography-mass spectroscopy (GC-MS) profiling of primary metabolites led to the detection of 135 peaks belonging to sugars, fatty acids/esters, amino acids, nitrogenous, and organic acids. Monosaccharides were detected at much higher levels in ripe fruit and disaccharides in predominate unripe fruits, whereas B. aegyptiaca vegetative parts (leaves and stem) were rich in amino acids and fatty acids. The antidiabetic compounds, viz, nicotinic acid, and trigonelline, were detected in all parts especially unripe fruit in addition to the sugar alcohol D-pinitol for the first time providing novel evidence for B. aegyptiaca use in diabetes. In vitro cytotoxic activity revealed the potential efficacy of immature fruit and seeds as cytotoxic agents against human prostate cancer (PC3) and human colorectal cancer (HCT-116) cell lines. Collectively, such detailed profiling of parts provides novel evidence for B. aegyptiaca medicinal uses. A2 - C1 - Bioorganic Chemistry ER - TY - JOUR ID - 230 TI - Synthesis, crystallographic structure, theoretical analysis, molecular docking studies, and biological activity evaluation of Binuclear Ru(II)-1-Naphthylhydrazine Complex JO - Int. J. Mol. Sci. PY - 2023 SP - 689 AU - Eichhorn, T. AU - Kolbe, F. AU - Mišić, S. AU - Dimić, D. AU - Morgan, I. AU - Saoud, M. AU - Milenković, D. AU - Marković, Z. AU - Rüffer, T. AU - Dimitrić Marković, J. AU - Kaluđerović, G. N. AU - VL - 24 UR - https://doi.org/10.3390/ijms24010689 DO - 10.3390/ijms24010689 AB - Ruthenium(II)–arene complexes have gained significant research interest due to their possible application in cancer therapy. In this contribution two new complexes are described, namely [{RuCl(η6-p-cymene)}2(μ-Cl)(μ-1-N,N′-naphthyl)]X (X = Cl, 1; PF6, 2), which were fully characterized by IR, NMR, and elemental microanalysis. Furthermore, the structure of 2 in the solid state was determined by a single crystal X-ray crystallographic study, confirming the composition of the crystals as 2·2MeOH. The Hirshfeld surface analysis was employed for the investigation of interactions that govern the crystal structure of 2·2MeOH. The structural data for 2 out of 2·2MeOH was used for the theoretical analysis of the cationic part [{RuCl(η6-p-cymene)}2(μ-Cl)(μ-1-N,N′-naphthyl)]+ (2a) which is common to both 1 and 2. The density functional theory, at B3LYP/6-31+G(d,p) basis set for H, C, N, and Cl atoms and LanL2DZ for Ru ions, was used for the optimization of the 2a structure. The natural bond orbital and quantum theory of atoms in molecules analyses were employed to quantify the intramolecular interactions. The reproduction of experimental IR and NMR spectra proved the applicability of the chosen level of theory. The binding of 1 to bovine serum albumin was examined by spectrofluorimetry and molecular docking, with complementary results obtained. Compound 1 acted as a radical scavenger towards DPPH• and HO• radicals, along with high activity towards cancer prostate and colon cell lines. A2 - C1 - Bioorganic Chemistry ER - TY - JOUR ID - 227 TI - 12-Oxophytodienoate reductase overexpression compromises tolerance to Botrytis cinerea in hexaploid and tetraploid wheat JO - Plants PY - 2023 SP - 2050 AU - Degtyaryov, E. AU - Pigolev, A. AU - Miroshnichenko, D. AU - Frolov, A. AU - Basnet, A. T. AU - Gorbach, D. AU - Leonova, T. AU - Pushin, A. S. AU - Alekseeva, V. AU - Dolgov, S. AU - Savchenko, T. AU - VL - 12 UR - https://doi.org/10.3390/plants12102050 DO - 10.3390/plants12102050 AB - 12-Oxophytodienoate reductase is the enzyme involved in the biosynthesis of phytohormone jasmonates, which are considered to be the major regulators of plant tolerance to biotic challenges, especially necrotrophic pathogens. However, we observe compromised tolerance to the necrotrophic fungal pathogen Botrytis cinerea in transgenic hexaploid bread wheat and tetraploid emmer wheat plants overexpressing 12-OXOPHYTODIENOATE REDUCTASE-3 gene from Arabidopsis thaliana, while in Arabidopsis plants themselves, endogenously produced and exogenously applied jasmonates exert a strong protective effect against B. cinerea. Exogenous application of methyl jasmonate on hexaploid and tetraploid wheat leaves suppresses tolerance to B. cinerea and induces the formation of chlorotic damages. Exogenous treatment with methyl jasmonate in concentrations of 100 µM and higher causes leaf yellowing even in the absence of the pathogen, in agreement with findings on the role of jasmonates in the regulation of leaf senescence. Thereby, the present study demonstrates the negative role of the jasmonate system in hexaploid and tetraploid wheat tolerance to B. cinerea and reveals previously unknown jasmonate-mediated responses. A2 - C1 - Bioorganic Chemistry ER - TY - JOUR ID - 224 TI - Prenylated acylphloroglucinol alcohols and peroxides from Hypericum coris JO - Phytochem. Lett. PY - 2023 SP - 11-15 AU - Corrêa dos Santos, C. H. AU - Stark, P. AU - Rizzo, P. AU - Franke, K. AU - Wessjohann, L. AU - VL - 57 UR - https://doi.org/10.1016/j.phytol.2023.07.011 DO - 10.1016/j.phytol.2023.07.011 AB - Two so far undescribed prenylated acylphloroglucinol derivatives were isolated from Hypericum coris (hypercorisins A-B) together with their two, also yet undescribed, peroxide derivatives (hypercorisins C-D), and seven known compounds (2-geranyloxy-1-(2-methylpropanoyl)-phloroglucinol, sucrose, vanillic acid 4-O-β-D-glucoside, chlorogenic acid, neochlorogenic acid, shikimic acid, quercitrin). The structures were determined by means of 1D and 2D NMR experiments and high-resolution mass spectrometry. Hypercorisins A, B and D induced complete inhibition of the gram-positive bacterium Bacillus subtilis at the highest concentration tested (100 μM) but showed no appreciable antibacterial effect on the gram-negative Aliivibrio fischeri nor cytotoxic activity on PC-3 or HCT-116 cancer cell lines. A2 - C1 - Bioorganic Chemistry ER - TY - JOUR ID - 277 TI - Triphenyltin(IV) carboxylates with exceptionally high cytotoxicity against different breast cancer cell lines JO - Biomolecules PY - 2023 SP - 595 AU - Predarska, I. AU - Saoud, M. AU - Morgan, I. AU - Lönnecke, P. AU - Kaluđerović, G. N. AU - Hey-Hawkins, E. AU - VL - 13 UR - https://doi.org/10.3390/biom13040595 DO - 10.3390/biom13040595 AB - Organotin(IV) carboxylates are a class of compounds explored as alternatives to platinum-containing chemotherapeutics due to propitious in vitro and in vivo results, and distinct mechanisms of action. In this study, triphenyltin(IV) derivatives of non-steroidal anti-inflammatory drugs (indomethacin (HIND) and flurbiprofen (HFBP)) are synthesized and characterized, namely [Ph3Sn(IND)] and [Ph3Sn(FBP)]. The crystal structure of [Ph3Sn(IND)] reveals penta-coordination of the central tin atom with almost perfect trigonal bipyramidal geometry with phenyl groups in the equatorial positions and two axially located oxygen atoms belonging to two distinct carboxylato (IND) ligands leading to formation of a coordination polymer with bridging carboxylato ligands. Employing MTT and CV probes, the antiproliferative effects of both organotin(IV) complexes, indomethacin, and flurbiprofen were evaluated on different breast carcinoma cells (BT-474, MDA-MB-468, MCF-7 and HCC1937). [Ph3Sn(IND)] and [Ph3Sn(FBP)], unlike the inactive ligand precursors, were found extremely active towards all examined cell lines, demonstrating IC50 concentrations in the range of 0.076–0.200 µM. Flow cytometry was employed to examine the mode of action showing that neither apoptotic nor autophagic mechanisms were triggered within the first 48 h of treatment. However, both tin(IV) complexes inhibited cell proliferation potentially related to the dramatic reduction in NO production, resulting from downregulation of nitric oxide synthase (iNOS) enzyme expression. A2 - C1 - Bioorganic Chemistry ER - TY - JOUR ID - 404 TI - Dissecting coffee seeds metabolome in context of genotype, roasting degree, and blending in the Middle East using NMR and GC/MS techniques JO - Food Chem. PY - 2022 SP - 131452 AU - Zayed, A. AU - Abdelwareth, A. AU - Mohamed, T. A. AU - Fahmy, H. A. AU - Porzel, A. AU - Wessjohann, L. A. AU - Farag, M. A. AU - VL - 373 UR - https://doi.org/10.1016/j.foodchem.2021.131452 DO - 10.1016/j.foodchem.2021.131452 AB - With a favored taste and various bioactivities, coffee has been consumed as a daily beverage worldwide. The current study presented a multi-faceted comparative metabolomics approach dissecting commercially available coffee products in the Middle East region for quality assessment and functional food purposes using NMR and GC/MS platforms. NMR metabolites fingerprinting led to identification of 18 metabolites and quantification (qNMR) of six prominent markers for standardization purposes. An increase of β-ethanolamine (MEA) reported for the first time, 5-(hydroxymethyl) furfural (5-HMF), concurrent with a reduction in chlorogenic acid, kahweol, and sucrose levels post roasting as revealed using multivariate data analyses (MVA). The diterpenes kahweol and cafestol were identified in green and roasted Coffea arabica, while 16-O-methyl cafestol in roasted C. robusta. Moreover, GC/MS identified a total of 143 metabolites belonging to 15 different chemical classes, with fructose found enriched in green C. robusta versus fatty acids abundance, i.e., palmitic and stearic acids in C. arabica confirming NMR results. These potential results aided to identify novel quality control attributes, i.e., ethanolamine, for coffee in the Middle East region and have yet to be confirmed in other coffee specimens. A2 - C1 - Bioorganic Chemistry ER - TY - JOUR ID - 399 TI - Heterocyclic and alkyne terpenoids by terpene synthase‐mediated biotransformation of non‐natural prenyl diphosphates: Access to new fragrances and probes JO - ChemBioChem PY - 2022 SP - e202200211 AU - Weigel, B. AU - Ludwig, J. AU - Weber, R. A. AU - Ludwig, S. AU - Lennicke, C. AU - Schrank, P. AU - Davari, M. D. AU - Nagia, M. AU - Wessjohann, L. A. AU - VL - 23 UR - https://doi.org/10.1002/cbic.202200211 DO - 10.1002/cbic.202200211 AB - Terpene synthase-mediated biotransformation of eleven synthetic sulfur- or oxygen-containing non-natural prenyl diphosphates resulted in the formation of five novel terpenoids and analogues. Uniquely, they trap intermediate steps and form heterocycles or compounds with alkyne side chains. Computational modelling differentiates convertible from inconvertible substrates and thereby provides an understanding of the detailed molecular mechanism of terpene cyclases. Two terpene cyclases were used as biocatalytic tool, namely, limonene synthase from Cannabis sativa (CLS) and 5-epi-aristolochene synthase (TEAS) from Nicotiana tabacum. They showed significant substrate flexibility towards non-natural prenyl diphosphates to form novel terpenoids, including core oxa- and thia-heterocycles and alkyne-modified terpenoids. We elucidated the structures of five novel monoterpene-analogues and a known sesquiterpene-analogue. These results reflected the terpene synthases′ ability and promiscuity to broaden the pool of terpenoids with structurally complex analogues. Docking studies highlight an on-off conversion of the unnatural substrates. A2 - C1 - Bioorganic Chemistry ER - TY - JOUR ID - 393 TI - Multicomponent functionalization of the octreotide peptide macrocyclic scaffold JO - Eur. J. Org. Chem. PY - 2022 SP - e202200687 AU - Vasco, A. V. AU - Ceballos, L. G. AU - Wessjohann, L. A. AU - Rivera, D. G. AU - VL - 2022 UR - https://doi.org/10.1002/ejoc.202200687 DO - 10.1002/ejoc.202200687 AB - The replacement of the disulfide bridge by other types of side chain linkages has been a continuous endeavor in the development of cyclic peptide drugs with improved metabolic stability. Octreotide is a potent and selective somatostatin analog that has been used as an anticancer agent, in radiolabeled conjugates for the localization of tumors and as targeting moiety in peptide-drug conjugates. Here, we describe an onresin methodology based on a multicomponent macrocyclization that enables the substitution of the disulfide bond by a tertiary lactam bridge functionalized with a variety of exocyclic moieties, including lipids, fluorophores, and charged groups. Conformational analysis in comparison with octreotide provides key information on the type of functionalization permitting the conformational mimicry of the bioactive peptide. A2 - C1 - Bioorganic Chemistry ER - TY - JOUR ID - 387 TI - Dynamics of Reactive Carbonyl Species in Pea Root Nodules in Response to Polyethylene Glycol (PEG)-Induced Osmotic Stress JO - Int. J. Mol. Sci. PY - 2022 SP - 2726 AU - Soboleva, A. AU - Frolova, N. AU - Bureiko, K. AU - Shumilina, J. AU - Balcke, G. U. AU - Zhukov, V. A. AU - Tikhonovich, I. A. AU - Frolov, A. AU - VL - 23 UR - https://doi.org/10.3390/ijms23052726 DO - 10.3390/ijms23052726 AB - Drought dramatically affects crop productivity worldwide. For legumes this effect is especially pronounced, as their symbiotic association with rhizobia is highly-sensitive to dehydration. This might be attributed to the oxidative stress, which ultimately accompanies plants’ response to water deficit. Indeed, enhanced formation of reactive oxygen species in root nodules might result in up-regulation of lipid peroxidation and overproduction of reactive carbonyl compounds (RCCs), which readily modify biomolecules and disrupt cell functions. Thus, the knowledge of the nodule carbonyl metabolome dynamics is critically important for understanding the drought-related losses of nitrogen fixation efficiency and plant productivity. Therefore, here we provide, to the best of our knowledge, for the first time a comprehensive overview of the pea root nodule carbonyl metabolome and address its alterations in response to polyethylene glycol-induced osmotic stress as the first step to examine the changes of RCC patterns in drought treated plants. RCCs were extracted from the nodules and derivatized with 7-(diethylamino)coumarin-3-carbohydrazide (CHH). The relative quantification of CHH-derivatives by liquid chromatography-high resolution mass spectrometry with a post-run correction for derivative stability revealed in total 194 features with intensities above 1 × 105 counts, 19 of which were down- and three were upregulated. The upregulation of glyceraldehyde could accompany non-enzymatic conversion of glyceraldehyde-3-phosphate to methylglyoxal. The accumulation of 4,5-dioxovaleric acid could be the reason for down-regulation of porphyrin metabolism, suppression of leghemoglobin synthesis, inhibition of nitrogenase and degradation of legume-rhizobial symbiosis in response to polyethylene glycol (PEG)-induced osmotic stress effect. This effect needs to be confirmed with soil-based drought models. A2 - C1 - Bioorganic Chemistry; Cell and Metabolic Biology ER - TY - JOUR ID - 386 TI - Seed-to-seedling transition in Pisum sativum L.: A transcriptomic approach JO - Plants PY - 2022 SP - 1686 AU - Smolikova, G. AU - Strygina, K. AU - Krylova, E. AU - Vikhorev, A. AU - Bilova, T. AU - Frolov, A. AU - Khlestkina, E. AU - Medvedev, S. AU - VL - 11 UR - https://doi.org/10.3390/plants11131686 DO - 10.3390/plants11131686 AB - The seed-to-seedling transition is a crucial step in the plant life cycle. The transition occurs at the end of seed germination and corresponds to the initiation of embryonic root growth. To improve our understanding of how a seed transforms into a seedling, we germinated the Pisum sativum L. seeds for 72 h and divided them into samples before and after radicle protrusion. Before radicle protrusion, seeds survived after drying and formed normally developed seedlings upon rehydration. Radicle protrusion increased the moisture content level in seed axes, and the accumulation of ROS first generated in the embryonic root and plumule. The water and oxidative status shift correlated with the desiccation tolerance loss. Then, we compared RNA sequencing-based transcriptomics in the embryonic axes isolated from pea seeds before and after radicle protrusion. We identified 24,184 differentially expressed genes during the transition to the post-germination stage. Among them, 2101 genes showed more prominent expression. They were related to primary and secondary metabolism, photosynthesis, biosynthesis of cell wall components, redox status, and responses to biotic stress. On the other hand, 415 genes showed significantly decreased expression, including the groups related to water deprivation (eight genes) and response to the ABA stimulus (fifteen genes). We assume that the water deprivation group, especially three genes also belonging to ABA stimulus (LTI65, LTP4, and HVA22E), may be crucial for the desiccation tolerance loss during a metabolic switch from seed to seedling. The latter is also accompanied by the suppression of ABA-related transcription factors ABI3, ABI4, and ABI5. Among them, HVA22E, ABI4, and ABI5 were highly conservative in functional domains and showed homologous sequences in different drought-tolerant species. These findings elaborate on the critical biochemical pathways and genes regulating seed-to-seedling transition. A2 - C1 - Bioorganic Chemistry ER - TY - JOUR ID - 351 TI - Assessing phytoequivalency of four Zingiberaceae spices (galangals, turmeric and ginger) using a biochemometric approach: A case study JO - Industrial Crops and Products PY - 2022 SP - 115722 AU - Khattab, A. R. AU - Rasheed, D. M. AU - El-Haddad, A. E. AU - Porzel, A. AU - Wessjohann, L. A. AU - Farag, M. A. AU - VL - 188 UR - https://doi.org/10.1016/j.indcrop.2022.115722 DO - 10.1016/j.indcrop.2022.115722 AB - The Zingiberaceae family (the ginger family) encompasses featured candidates used extensively in perfume, dyes, medicine as well as food industries. This study provides NMR metabolite fingerprinting, quantification and biological evaluation of four major plants viz. lesser and greater galangal, curcuma and ginger. 1H NMR derived metabolite profiles of the four spices were modeled via orthogonal partial least squares discriminate analysis (OPLS-DA). The cytotoxic activity of the four plants against colon and prostate cancer cell lines and in-vitro cyclooxygenase-1 inhibition activity were also evaluated. A correlation between the plants’ bioactivities and their 1H NMR metabolite profiles was established using OPLS and revealed putative metabolites responsible for these bioactivities. The most active cytotoxic plant was greater galangal due to its enrichment in galangal acetate. In contrast, lesser galangal exhibited the strongest anti-inflammatory action being enriched in 5-hydroxy-7-(4ꞌ-hydroxy-3 ꞌ-methoxyphenyl)-1-phenyl-3-heptanone and kaempferide. This study provides insight on the potential medicinal merit of genus Alpinia comparable to the more explored drugs turmeric and ginger within the Zingiberaceae family. A2 - C1 - Bioorganic Chemistry ER - TY - JOUR ID - 333 TI - Authentication of saffron spice accessions from its common substitutes via a multiplex approach of UV/VIS fingerprints and UPLC/MS using molecular networking and chemometrics JO - Food Chem. PY - 2022 SP - 130739 AU - Hegazi, N. M. AU - Khattab, A. R. AU - Frolov, A. AU - Wessjohann, L. A. AU - Farag, M. A. AU - VL - 367 UR - https://doi.org/10.1016/j.foodchem.2021.130739 DO - 10.1016/j.foodchem.2021.130739 AB - Saffron is a spice revered for its unique flavor and health attributes often subjected to fraudulence. In this study, molecular networking as a visualization tool for UPLC/MS dataset of saffron and its common substitutes i.e. safflower and calendula (n = 21) was employed for determining genuineness of saffron and detecting its common substitutes i.e. safflower and calendula. Saffron was abundant in flavonol-O-glycosides and crocetin esters versus richness of flavanones/chalcones glycosides in safflower and cinnamates/terpenes in calendula. OPLS-DA identified differences in UPLC/MS profiles of different saffron accessions where oxo-hydroxy-undecenoic acid-O-hexoside was posed as saffron authentication marker and aided in discrimination between Spanish saffron of high quality from its inferior grade i.e. Iranian saffron along with crocetin di-O-gentiobiosyl ester and kaempferol-O-sophoroside. Kaempferol-O-neohesperidoside and N,N,N,-p-coumaroyl spermidine were characteristic safflower metabolites, whereas, calendulaglycoside C and di-O-caffeoyl quinic acid were unique to calendula. UV/VIS fingerprint spectral regions of picrocrocin (230–260 nm) and crocin derivatives (400–470 nm) were posed as being discriminatory of saffron authenticity and suggestive it can replace UPLC/MS in saffrom quality determination. A2 - C1 - Bioorganic Chemistry ER - TY - JOUR ID - 329 TI - Chemometric analysis based on GC-MS chemical profiles of three Stachys Species from Uzbekistan and their biological activity JO - Plants PY - 2022 SP - 1215 AU - Gad, H. A. AU - Mukhammadiev, E. A. AU - Zengin, G. AU - Musayeib, N. M. A. AU - Hussain, H. AU - Bin Ware, I. AU - Ashour, M. L. AU - Mamadalieva, N. Z. AU - VL - 11 UR - https://doi.org/10.3390/plants11091215 DO - 10.3390/plants11091215 AB - The chemical composition of the essential oils (EOs) of Stachys byzantina, S. hissarica and S. betoniciflora growing in Uzbekistan were determined, and their antioxidant and enzyme inhibitory activity were assessed. A gas chromatography-mass spectrometry (GC-MS) analysis revealed the presence of 143 metabolites accounting for 70.34, 76.78 and 88.63% of the total identified components of S. byzantina, S. hissarica and S. betoniciflora, respectively. Octadecanal (9.37%) was the most predominant in S. betoniciflora. However, n-butyl octadecenoate (4.92%) was the major volatile in S. byzantina. Benzaldehyde (5.01%) was present at a higher percentage in S. hissarica. A chemometric analysis revealed the ability of volatile profiling to discriminate between the studied Stachys species. The principal component analysis plot displayed a clear diversity of Stachys species where the octadecanal and benzaldehyde were the main discriminating markers. The antioxidant activity was evaluated in vitro using 2,2-diphenyl-1-picryl-hydrazyl (DPPH), 2,2-azino bis (3-ethylbenzothiazoline-6-sulphonic acid) (ABTS), cupric reducing antioxidant capacity (CUPRAC), ferric reducing power (FRAP), chelating and phosphomolybdenum (PBD). Moreover, the ability of the essential oils to inhibit both acetyl/butyrylcholinesterases (AChE and BChE), α-amylase, α-glucosidase and tyrosinase was assessed. The volatiles from S. hissarica exhibited the highest activity in both the ABTS (226.48 ± 1.75 mg Trolox equivalent (TE)/g oil) and FRAP (109.55 ± 3.24 mg TE/g oil) assays. However, S. betoniciflora displayed the strongest activity in the other assays (174.94 ± 0.20 mg TE/g oil for CUPRAC, 60.11 ± 0.36 mg EDTA equivalent (EDTAE)/g oil for chelating and 28.24 ± 1.00 (mmol TE/g oil) for PBD. Regarding the enzyme inhibitory activity, S. byzantina demonstrated the strongest AChE (5.64 ± 0.04 mg galantamine equivalent (GALAE)/g oil) and tyrosinase inhibitory (101.07 ± 0.60 mg kojic acid equivalent (KAE)/g) activity. The highest activity for BChE (11.18 ± 0.19 mg GALAE/g oil), amylase inhibition (0.76 ± 0.02 mmol acarbose equivalent (ACAE)/g oil) and glucosidase inhibition (24.11 ± 0.06 mmol ACAE/g oil) was observed in S. betoniciflora. These results showed that EOs of Stachys species could be used as antioxidant, hypoglycemic and skincare agents. A2 - C1 - Bioorganic Chemistry ER - TY - JOUR ID - 326 TI - Metabolomics-based approach for coffee beverage improvement in the context of processing, brewing methods, and quality attributes JO - Foods PY - 2022 SP - 864 AU - Farag, M. A. AU - Zayed, A. AU - Sallam, I. E. AU - Abdelwareth, A. AU - Wessjohann, L. A. AU - VL - 11 UR - https://doi.org/ 10.3390/foods11060864 DO - 10.3390/foods11060864 AB - Coffee is a worldwide beverage of increasing consumption, owing to its unique flavor and several health benefits. Metabolites of coffee are numerous and could be classified on various bases, of which some are endogenous to coffee seeds, i.e., alkaloids, diterpenes, sugars, and amino acids, while others are generated during coffee processing, for example during roasting and brewing, such as furans, pyrazines, and melanoidins. As a beverage, it provides various distinct flavors, i.e., sourness, bitterness, and an astringent taste attributed to the presence of carboxylic acids, alkaloids, and chlorogenic acids. To resolve such a complex chemical makeup and to relate chemical composition to coffee effects, large-scale metabolomics technologies are being increasingly reported in the literature for proof of coffee quality and efficacy. This review summarizes the applications of various mass spectrometry (MS)- and nuclear magnetic resonance (NMR)-based metabolomics technologies in determining the impact of coffee breeding, origin, roasting, and brewing on coffee chemical composition, and considers this in relation to quality control (QC) determination, for example, by classifying defected and non-defected seeds or detecting the adulteration of raw materials. Resolving the coffee metabolome can aid future attempts to yield coffee seeds of desirable traits and best flavor types. A2 - C1 - Bioorganic Chemistry ER - TY - JOUR ID - 319 TI - Albatrellus confluens (Alb. & Schwein.) Kotl. & Pouz.: Natural fungal compounds and synthetic derivatives with in vitro anthelmintic activities and antiproliferative effects against two human cancer cell lines JO - Molecules PY - 2022 SP - 2950 AU - Dube, M. AU - Llanes, D. AU - Saoud, M. AU - Rennert, R. AU - Imming, P. AU - Häberli, C. AU - Keiser, J. AU - Arnold, N. AU - VL - 27 UR - https://doi.org/10.3390/molecules27092950 DO - 10.3390/molecules27092950 AB - Neglected tropical diseases affect the world’s poorest populations with soil-transmitted helminthiasis and schistosomiasis being among the most prevalent ones. Mass drug administration is currently the most important control measure, but the use of the few available drugs is giving rise to increased resistance of the parasites to the drugs. Different approaches are needed to come up with new therapeutic agents against these helminths. Fungi are a source of secondary metabolites, but most fungi remain largely uninvestigated as anthelmintics. In this report, the anthelmintic activity of Albatrellus confluens against Caenorhabditis elegans was investigated using bio-assay guided isolation. Grifolin (1) and neogrifolin (2) were identified as responsible for the anthelmintic activity. Derivatives 4–6 were synthesized to investigate the effect of varying the prenyl chain length on anthelmintic activity. The isolated compounds 1 and 2 and synthetic derivatives 4–6, as well as their educts 7–10, were tested against Schistosoma mansoni (adult and newly transformed schistosomula), Strongyloides ratti, Heligmosomoides polygyrus, Necator americanus, and Ancylostoma ceylanicum. Prenyl-2-orcinol (4) and geranylgeranyl-2-orcinol (6) showed promising activity against newly transformed schistosomula. The compounds 1, 2, 4, 5, and 6 were also screened for antiproliferative or cytotoxic activity against two human cancer lines, viz. prostate adenocarcinoma cells (PC-3) and colorectal adenocarcinoma cells (HT-29). Compound 6 was determined to be the most effective against both cell lines with IC50 values of 16.1 µM in PC-3 prostate cells and 33.7 µM in HT-29 colorectal cells. A2 - C1 - Bioorganic Chemistry ER - TY - JOUR ID - 309 TI - Bioactive phenolic compounds from Peperomia obtusifolia JO - Molecules PY - 2022 SP - 4363 AU - Bin Ware, I. AU - Franke, K. AU - Hussain, H. AU - Morgan, I. AU - Rennert, R. AU - Wessjohann, L. A. AU - VL - 27 UR - https://doi.org/10.3390/molecules27144363 DO - 10.3390/molecules27144363 AB - Peperomia obtusifolia (L.) A. Dietr., native to Middle America, is an ornamental plant also traditionally used for its mild antimicrobial properties. Chemical investigation on the leaves of P. obtusifolia resulted in the isolation of two previously undescribed compounds, named peperomic ester (1) and peperoside (2), together with five known compounds, viz. N-[2-(3,4-dihydroxyphenyl)ethyl]-3,4-dihydroxybenzamide (3), becatamide (4), peperobtusin A (5), peperomin B (6), and arabinothalictoside (7). The structures of these compounds were elucidated by 1D and 2D NMR techniques and HREIMS analyses. Compounds 1–7 were evaluated for their anthelmintic (against Caenorhabditis elegans), antifungal (against Botrytis cinerea, Septoria tritici and Phytophthora infestans), antibacterial (against Bacillus subtilis and Aliivibrio fischeri), and antiproliferative (against PC-3 and HT-29 human cancer cell lines) activities. The known peperobtusin A (5) was the most active compound against the PC-3 cancer cell line with IC50 values of 25.6 µM and 36.0 µM in MTT and CV assays, respectively. This compound also induced 90% inhibition of bacterial growth of the Gram-positive B. subtilis at a concentration of 100 µM. In addition, compound 3 showed anti-oomycotic activity against P. infestans with an inhibition value of 56% by using a concentration of 125 µM. However, no anthelmintic activity was observed. A2 - C1 - Bioorganic Chemistry ER - TY - JOUR ID - 307 TI - The loss of polyphenol oxidase function is associated with hilum pigmentation and has been selected during pea domestication JO - New Phytol. PY - 2022 SP - 1807–1821 AU - Balarynová, J. AU - Klčová, B. AU - Sekaninová, J. AU - Kobrlová, L. AU - Cechová, M. Z. AU - Krejčí, P. AU - Leonova, T. AU - Gorbach, D. AU - Ihling, C. AU - Smržová, L. AU - Trněný, O. AU - Frolov, A. AU - Bednář, P. AU - Smýkal, P. AU - VL - 235 UR - https://doi.org/10.1111/nph.18256 DO - 10.1111/nph.18256 AB - Seed coats serve as protective tissue to the enclosed embryo. As well as mechanical there are also chemical defence functions. During domestication, the property of the seed coat was altered including the removal of the seed dormancy. We used a range of genetic, transcriptomic, proteomic and metabolomic approaches to determine the function of the pea seed polyphenol oxidase (PPO) gene. Sequencing analysis revealed one nucleotide insertion or deletion in the PPO gene, with the functional PPO allele found in all wild pea samples, while most cultivated peas have one of the three nonfunctional ppo alleles. PPO functionality cosegregates with hilum pigmentation. PPO gene and protein expression, as well as enzymatic activity, was downregulated in the seed coats of cultivated peas. The functionality of the PPO gene relates to the oxidation and polymerisation of gallocatechin in the seed coat. Additionally, imaging mass spectrometry supports the hypothesis that hilum pigmentation is conditioned by the presence of both phenolic precursors and sufficient PPO activity. Taken together these results indicate that the nonfunctional polyphenol oxidase gene has been selected during pea domestication, possibly due to better seed palatability or seed coat visual appearance. A2 - C1 - Bioorganic Chemistry ER - TY - JOUR ID - 378 TI - Mesoporous silica nanoparticles enhance the anticancer efficacy of platinum(IV)-phenolate conjugates in breast cancer cell lines JO - Nanomaterials PY - 2022 SP - 3767 AU - Predarska, I. AU - Saoud, M. AU - Drača, D. AU - Morgan, I. AU - Komazec, T. AU - Eichhorn, T. AU - Mihajlović, E. AU - Dunđerović, D. AU - Mijatović, S. AU - Maksimović-Ivanić, D. AU - Hey-Hawkins, E. AU - Kaluđerović, G. N. AU - VL - 12 UR - https://doi.org/10.3390/nano12213767 DO - 10.3390/nano12213767 AB - The main reasons for the limited clinical efficacy of the platinum(II)-based agent cisplatin include drug resistance and significant side effects. Due to their better stability, as well as the possibility to introduce biologically active ligands in their axial positions constructing multifunctional prodrugs, creating platinum(IV) complexes is a tempting strategy for addressing these limitations. Another strategy for developing chemotherapeutics with lower toxicity relies on the ability of nanoparticles to accumulate in greater quantities in tumor tissues through passive targeting. To combine the two approaches, three platinum(IV) conjugates based on a cisplatin scaffold containing in the axial positions derivatives of caffeic and ferulic acid were prepared and loaded into SBA-15 to produce the corresponding mesoporous silica nanoparticles (MSNs). The free platinum(IV) conjugates demonstrated higher or comparable activity with respect to cisplatin against different human breast cancer cell lines, while upon immobilization, superior antiproliferative activity with markedly increased cytotoxicity (more than 1000-fold lower IC50 values) compared to cisplatin was observed. Mechanistic investigations with the most potent conjugate, cisplatin-diacetyl caffeate (1), and the corresponding MSNs (SBA-15|1) in a 4T1 mouse breast cancer cell line showed that these compounds induce apoptotic cell death causing strong caspase activation. In vivo, in BALB/c mice, 1 and SBA-15|1 inhibited the tumor growth while decreasing the necrotic area and lowering the mitotic rate. A2 - C1 - Bioorganic Chemistry ER - TY - JOUR ID - 377 TI - Cisplatin−cyclooxygenase inhibitor conjugates, free and immobilised in mesoporous silica SBA-15, prove highly potent against triple-negative MDA-MB-468 breast cancer cell line JO - Dalton Trans. PY - 2022 SP - 857–869 AU - Predarska, I. AU - Saoud, M. AU - Morgan, I. AU - Eichhorn, T. AU - Kaluđerović, G. N. AU - Hey-Hawkins, E. AU - VL - 51 UR - https://doi.org/10.1039/D1DT03265H DO - 10.1039/d1dt03265h AB - For the development of anticancer drugs with higher activity and reduced toxicity, two approaches were combined: preparation of platinum(IV) complexes exhibiting higher stability compared to their platinum(II) counterparts and loading them into mesoporous silica SBA-15 with the aim to utilise the passive enhanced permeability and retention (EPR) effect of nanoparticles for accumulation in tumour tissues. Three conjugates based on a cisplatin scaffold bearing the anti-inflammatory drugs naproxen, ibuprofen or flurbiprofen in the axial positions (1, 2 and 3, respectively) were synthesised and loaded into SBA-15 to afford the mesoporous silica nanoparticles (MSNs) SBA-15|1, SBA-15|2 and SBA-15|3. Superior antiproliferative activity of both free and immobilised conjugates in a panel of four breast cancer cell lines (MDA-MB-468, HCC1937, MCF-7 and BT-474) with markedly increased cytotoxicity with respect to cisplatin was demonstrated. All compounds exhibit highest activity against the triple-negative cell line MDA-MB-468, with conjugate 1 being the most potent. However, against MCF-7 and BT-474 cell lines, the most notable improvement was found, with IC50 values up to 240-fold lower than cisplatin. Flow cytometry assays clearly show that all compounds induce apoptotic cell death elevating the levels of both early and late apoptotic cells. Furthermore, autophagy as well as formation of reactive oxygen species (ROS) and nitric oxide (NO) were elevated to a similar or greater extent than with cisplatin. A2 - C1 - Bioorganic Chemistry ER - TY - JOUR ID - 368 TI - Structural elucidation of an atropisomeric entcassiflavan-(4β→8)-epicatechin isolated from Dalbergia monetaria L.f. based on NMR and ECD calculations in comparison to experimental data JO - Molecules PY - 2022 SP - 2512 AU - Moura, P. H. B. AU - Brandt, W. AU - Porzel, A. AU - Martins, R. C. C. AU - Leal, I. C. R. AU - Wessjohann, L. A. AU - VL - 27 UR - https://doi.org/10.3390/molecules27082512 DO - 10.3390/molecules27082512 AB - A rare dihydoxyflavan-epicatechin proanthocyanidin, entcassiflavan-(4β→8)-epicatechin, was isolated from Dalbergia monetaria, a plant widely used by traditional people from the Amazon to treat urinary tract infections. The constitution and relative configuration of the compound were elucidated by HR-MS and detailed 1D- and 2D-NMR measurements. By comparing the experimental electronic circular dichroism (ECD) spectrum with the calculated ECD spectra of all 16 possible isomers, the absolute configuration, the interflavan linkage, and the atropisomers could be determined. A2 - C1 - Bioorganic Chemistry ER - TY - JOUR ID - 356 TI - Does filter-aided sample preparation provide sufficient method linearity for quantitative plant shotgun proteomics? JO - Front. Plant Sci. PY - 2022 SP - 874761 AU - Leonova, T. AU - Ihling, C. AU - Saoud, M. AU - Frolova, N. AU - Rennert, R. AU - Wessjohann, L. A. AU - Frolov, A. AU - VL - 13 UR - https://doi.org/10.3389/fpls.2022.874761 DO - 10.3389/fpls.2022.874761 AB - Due to its outstanding throughput and analytical resolution, gel-free LC-based shotgun proteomics represents the gold standard of proteome analysis. Thereby, the efficiency of sample preparation dramatically affects the correctness and reliability of protein quantification. Thus, the steps of protein isolation, solubilization, and proteolysis represent the principal bottleneck of shotgun proteomics. The desired performance of the sample preparation protocols can be achieved by the application of detergents. However, these compounds ultimately compromise reverse-phase chromatographic separation and disrupt electrospray ionization. Filter-aided sample preparation (FASP) represents an elegant approach to overcome these limitations. Although this method is comprehensively validated for cell proteomics, its applicability to plants and compatibility with plant-specific protein isolation protocols remain to be confirmed. Thereby, the most important gap is the absence of the data on the linearity of underlying protein quantification methods for plant matrices. To fill this gap, we address here the potential of FASP in combination with two protein isolation protocols for quantitative analysis of pea (Pisum sativum) seed and Arabidopsis thaliana leaf proteomes by the shotgun approach. For this aim, in comprehensive spiking experiments with bovine serum albumin (BSA), we evaluated the linear dynamic range (LDR) of protein quantification in the presence of plant matrices. Furthermore, we addressed the interference of two different plant matrices in quantitative experiments, accomplished with two alternative sample preparation workflows in comparison to conventional FASP-based digestion of cell lysates, considered here as a reference. The spiking experiments revealed high sensitivities (LODs of up to 4 fmol) for spiked BSA and LDRs of at least 0.6 × 102. Thereby, phenol extraction yielded slightly better recoveries, whereas the detergent-based method showed better linearity. Thus, our results indicate the very good applicability of FASP to quantitative plant proteomics with only limited impact of the protein isolation technique on the method’s overall performance. A2 - C1 - Bioorganic Chemistry ER - TY - JOUR ID - 355 TI - Agar-based polyethylene glycol (PEG) infusion model for pea (Pisum sativum L.) — perspectives of translation to legume crop plants JO - Biol. Commun. PY - 2022 SP - 236-244 AU - Leonova, T. AU - Shumilina, J. AU - Kim, A. AU - Frolova, N. AU - Wessjohann, L. AU - Bilova, T. AU - Frolov, A. AU - VL - 67 UR - https://doi.org/10.21638/spbu03.2022.309 DO - 10.21638/spbu03.2022.309 AB - Due to the oncoming climate changes water deficit represents one of the most important abiotic stressors which dramatically affects crop productivity worldwide. Because of their importance as the principal source of food protein, legumes attract a special interest of plant scientists. Moreover, legumes are involved in symbiotic association with rhizobial bacteria, which is morphologically localized to root nodules. These structures are critical for fixation of atmospheric nitrogen and highly sensitive to drought. Therefore, new drought-tolerant legume cultivars need to be developed to meet the growing food demand. However, this requires a comprehensive knowledge of the molecular mechanisms behind the plant stress response. To access these mechanisms, adequate and reliable drought stress models need to be established. The agar-based polyethylene glycol (PEG) infusion model allows a physiologically relevant reduction of soil water potential (Ψw), although it is restricted to seedlings and does not give access to proteomics and metabolomics studies. Earlier, we successfully overcame this limitation and optimized this model for mature Arabidopsis plants. Here we make the next step forward and address its application to one of the major crop legumes — pea. Using a broad panel of physiological and biochemical markers, we comprehensively prove the applicability of this setup to legumes. The patterns of drought-related physiological changes are well-interpretable and generally resemble the stress response of plants grown in soil-based stop-watering models. Thus, the proposed model can be efficiently used in the study of stress-related metabolic adjustment in green parts, roots and root nodules of juvenile and flowering plants. A2 - C1 - Bioorganic Chemistry ER - TY - JOUR ID - 420 TI - Machine learning-supported analyses improve quantitative histological assessments of amyloid-β deposits and activated Microglia JO - J. Alzheimers Dis. PY - 2021 SP - 597-605 AU - Bascuñana, P. AU - Brackhan, M. AU - Pahnke, J. AU - VL - 79 UR - https://content.iospress.com/articles/journal-of-alzheimers-disease/jad201120 DO - 10.3233/JAD-201120 AB - Background: Detailed pathology analysis and morphological quantification is tedious and prone to errors. Automatic image analysis can help to increase objectivity and reduce time. Here, we present the evaluation of the DeePathology STUDIO™ for automatic analysis of histological whole-slide images using machine learning/artificial intelligence. Objective: To evaluate and validate the use of DeePathology STUDIO for the analysis of histological slides at high resolution. Methods: We compared the DeePathology STUDIO and our current standard method using macros in AxioVision for the analysis of amyloid-β (Aβ) plaques and microglia in APP-transgenic mice at different ages. We analyzed density variables and total time invested with each approach. In addition, we correlated Aβ concentration in brain tissue measured by ELISA with the results of Aβ staining analysis. Results: DeePathology STUDIO showed a significant decrease of the time for establishing new analyses and the total analysis time by up to 90%. On the other hand, both approaches showed similar quantitative results in plaque and activated microglia density in the different experimental groups. DeePathology STUDIO showed higher sensitivity and accuracy for small-sized plaques. In addition, DeePathology STUDIO allowed the classification of plaques in diffuse- and dense-packed, which was not possible with our traditional analysis. Conclusion: DeePathology STUDIO substantially reduced the effort needed for a new analysis showing comparable quantitative results to the traditional approach. In addition, it allowed including different objects (categories) or cell types in a single analysis, which is not possible with conventional methods. A2 - C1 - Bioorganic Chemistry ER - TY - JOUR ID - 409 TI - Structural characterization of plant glucosylceramides and thecorresponding ceramides by UHPLC-LTQ-Orbitrap mass spectrometry JO - J. Pharm. Biomed. Anal. PY - 2021 SP - 113677 AU - Adem, A. A. AU - Belete, A. AU - Soboleva, A. AU - Frolov, A. AU - Tessema, E. N. AU - Gebre-Mariam, T. AU - Neubert, R. H. AU - VL - 192 UR - https://doi.org/10.1016/j.jpba.2020.113677 DO - 10.1016/j.jpba.2020.113677 AB - Ceramides (CERs) play a major role in skin barrier function and direct replacement of depleted skin CERs,due to skin disorder or aging, has beneficial effects in improving skin barrier function and skin hydration.Though, plants are reliable source of CERs, absence of economical and effective method of hydrolysis toconvert the dominant plant sphingolipid, glucosylceramides (GlcCERs), into CERs remains a challenge.This study aims at exploring alternative GlcCERs sources and chemical method of hydrolysis into CERsfor dermal application. GlcCERs isolated from lupin bean (Lupinus albus), mung bean (Vigna radiate) andnaked barley (Hordium vulgare) were identified using ultra high performance liquid chromatographyhyphenated with atmospheric pressure chemical ionization - high resolution tandem mass spectrometer(UHPLC/APCI-HRMS/MS) and quantified with validated automated multiple development-high perfor-mance thin layer chromatography (AMD-HPTLC) method. Plant GlcCERs were hydrolyzed into CERs withmild acid hydrolysis (0.1 N HCl) after treating them with oxidizing agent, NaIO4,and reducing agent,NaBH4. GlcCERs with 4,8-sphingadienine, 8-sphingenine and 4-hydroxy-8-sphingenine sphingoid baseslinked with C14 to C26 -hydroxylated fatty acids (FAs) were identified. Single GlcCER (m/z 714.5520)was dominant in lupin and mung beans while five major GlcCERs species (m/z 714.5520, m/z 742.5829,m/z 770.6144, m/z 842.6719 and m/z 844.56875) were obtained from naked barley. The GlcCERs con-tents of the three plants were comparable. However, lupin bean contains predominantly (> 98 %) a singleGlcCER (m/z 714.5520). Considering the affordability, GlcCER content and yield, lupin bean would bethe preferred alternative commercial source of GlcCERs. CER species bearing 4,8-sphingadienine and 8-sphingenine sphingoid bases attached to C14 to 24 FAs were found after mild acid hydrolysis. CER specieswith m/z 552.4992 was the main component in the beans while CER with m/z 608.5613 was dominantin the naked barley. However, CERs with 4-hydroxy-8-sphingenine sphingoid base were not detected inUHPLC-HRMS/MS study suggesting that the method works for mainly GlcCERs carrying dihydroxy sph-ingoid bases. The method is economical and effective which potentiates the commercialization of plantCERs for dermal application. A2 - C1 - Bioorganic Chemistry ER - TY - JOUR ID - 443 TI - Probing glycation potential of dietary sugars in human blood by anintegrated in vitro approach JO - Food Chem. PY - 2021 SP - 128951 AU - Frolova, N. AU - Soboleva, A. AU - Nguyen, V. D. AU - Kim, A. AU - Ihling, C. AU - Eisenschmidt-Bönn, D. AU - Mamontova, T. AU - Herfurth, U. M. AU - Wessjohann, L. A. AU - Sinz, A. AU - Birkenmeyer, C. AU - Frolov, A. AU - VL - 347 UR - https://doi.org/10.1016/j.foodchem.2020.128951 DO - 10.1016/j.foodchem.2020.128951 AB - Glycation is referred to as the interaction of protein amino and guanidino groups with reducing sugars and carbonyl products of their degradation. Resulting advanced glycation end-products (AGEs) contribute to pathogenesis of diabetes mellitus and neurodegenerative disorders. Upon their intestinal absorption, dietary sugars and á-dicarbonyl compounds interact with blood proteins yielding AGEs. Although the differences in glycation potential of monosaccharides are well characterized, the underlying mechanisms are poorly understood. To address this question, D-glucose, D-fructose and L-ascorbic acid were incubated with human serum albumin (HSA). The sugars and á-dicarbonyl intermediates of their degradation were analyzed in parallel to protein glycation patterns (exemplified with hydroimidazolone modifications of arginine residues and products of their hydrolysis) by bottom-up proteomics and computational chemistry. Glycation of HSA with sugars revealed 9 glyoxal- and 14 methylglyoxal-derived modification sites. Their dynamics was sugar-specific and depended on concentrations of á-dicarbonyls, their formation kinetics, and presence of stabilizing residues in close proximity to the glycation sites. A2 - C1 - Bioorganic Chemistry ER - TY - JOUR ID - 440 TI - Downy mildew resistance is genetically mediated by prophylactic production of phenylpropanoids in hop JO - Plant Cell Environ. PY - 2021 SP - 323-338 AU - Feiner, A. AU - Pitra, N. AU - Matthews, P. AU - Pillen, K. AU - Wessjohann, L. A. AU - Riewe, D. AU - VL - 44 UR - https://onlinelibrary.wiley.com/doi/10.1111/pce.13906 DO - 10.1111/pce.13906 AB - Downy mildew in hop (Humulus lupulus L.) is caused by Pseudoperonospora humuli and generates significant losses in quality and yield. To identify the biochemical processes that confer natural downy mildew resistance (DMR), a metabolome- and genomewide association study was performed. Inoculation of a high density genotyped F1 hop population (n = 192) with the obligate biotrophic oomycete P. humuli led to variation in both the levels of thousands of specialized metabolites and DMR. We observed that metabolites of almost all major phytochemical classes were induced 48 hr after inoculation. But only a small number of metabolites were found to be correlated with DMR and these were enriched with phenylpropanoids. These metabolites were also correlated with DMR when measured from the non-infected control set. A genome-wide association study revealed co-localization of the major DMR loci and the phenylpropanoid pathway markers indicating that the major contribution to resistance is mediated by these metabolites in a heritable manner. The application of three putative prophylactic phenylpropanoids led to a reduced degree of leaf infection in susceptible genotypes, confirming their protective activity either directly or as precursors of active compounds. A2 - C1 - Bioorganic Chemistry ER - TY - JOUR ID - 439 TI - UPLC-MS Metabolome-Based Seed Classification of 16 Vicia Species: A Prospect for Phyto-Equivalency and Chemotaxonomy of Different Accessions JO - J. Agr. Food Chem. PY - 2021 SP - 5252-5266 AU - Fayek, N. M. AU - Mekky, R. H. AU - Dias, C. N. AU - Kropf, M. AU - Heiss, A. G. AU - Wessjohann, L. A. AU - Farag, M. A. AU - VL - 69 UR - DO - 10.1021/acs.jafc.0c06054 AB - Seeds of domesticated Vicia (vetch) species (family Fabaceae-Faboideae) are produced and consumed worldwide for their nutritional value. Seed accessions belonging to 16 different species of Vicia—both domesticated and wild taxa—were subjected to a chemotaxonomic study using ultraperformance liquid chromatography–mass spectrometry (UPLC-MS) analyzed by chemometrics. A total of 89 metabolites were observed in the examined Vicia accessions. Seventy-eight out of the 89 detected metabolites were annotated. Metabolites quantified belonged to several classes, viz., flavonoids, procyanidins, prodelphinidins, anthocyanins, stilbenes, dihydrochalcones, phenolic acids, coumarins, alkaloids, jasmonates, fatty acids, terpenoids, and cyanogenics, with flavonoids and fatty acids amounting to the major classes. Flavonoids, fatty acids, and anthocyanins showed up as potential chemotaxonomic markers in Vicia species discrimination. Fatty acids were more enriched in Vicia faba specimens, while the abundance of flavonoids was the highest in Vicia parviflora. Anthocyanins allowed for discrimination between Vicia hirsuta and Vicia sepium. To the best of our knowledge, this is the first report on employing UPLC-MS metabolomics to discern the diversity of metabolites at the intrageneric level among Vicia species. A2 - C1 - Bioorganic Chemistry ER - TY - JOUR ID - 438 TI - Unraveling the metabolome composition and its implication for Salvadora persica L. use as dental brush via a multiplex approach of NMR and LC–MS metabolomics JO - J. Pharm. Biomed. Anal. PY - 2021 SP - 113727 AU - Farag, M. A. AU - Shakour, Z. T. AU - Lübken, T. AU - Frolov, A. AU - Wessjohann, L. A. AU - Mahrous, E. AU - VL - 193 UR - https://doi.org/10.1016/j.jpba.2020.113727 DO - 10.1016/j.jpba.2020.113727 AB - Salvadora persica L. (toothbrush tree, Miswak) is well recognized in most Middle Eastern and African countries for its potential role in dental care, albeit the underlying mechanism for its effectiveness is still not fully understood. A comparative MS and NMR metabolomics approach was employed to investigate the major primary and secondary metabolites composition of S. persica in context of its organ type viz., root or stem to rationalize for its use as a tooth brush. NMR metabolomics revealed its enrichment in nitrogenous compounds including proline-betaines i.e., 4-hydroxy-stachydrine and stachydrine reported for the first time in S. persica. LC/MS metabolomics identified flavonoids (8), benzylurea derivatives (5), butanediamides (3), phenolic acids (8) and 5 sulfur compounds, with 21 constituents reported for the first time in S. persica. Principal component analysis (PCA) and hierarchical cluster analysis (HCA) of either NMR or LC/MS dataset clearly separated stem from root specimens based on nitrogenous compounds abundance in roots and is justifying for its preference as toothbrush versus stems. The presence of betaines at high levels in S. persica (9−12 μg/mg dry weight) offers novel insights into its functioning as an osmoprotectant that maintains the hydration of oral mucosa. Additionally, the previously described anti-inflammatory activity of stachydrine along with the antimicrobial effects of sulfonated flavonoids, benzylisothiocynate and ellagic acid derivatives are likely contributors to S. persica oral hygiene health benefits. Among root samples, variation in sugars and organic acids levels were the main discriminatory criterion. This study provides the first standardization of S. persica extract using qNMR for further inclusion in nutraceuticals. A2 - C1 - Bioorganic Chemistry ER - TY - JOUR ID - 437 TI - Nuclear magnetic resonance metabolomics approach for the analysis of major legume sprouts coupled to chemometrics JO - Molecules PY - 2021 SP - 761 AU - Farag, M. A. AU - Sharaf El-Din, M. G. AU - Selim, M. A. AU - Owis, A. I. AU - Abouzid, S. F. AU - Porzel, A. AU - Wessjohann, L. A. AU - Otify, A. AU - VL - 26 UR - https://www.mdpi.com/1420-3049/26/3/761 DO - 10.3390/molecules26030761 AB - Legume sprouts are a fresh nutritive source of phytochemicals of increasing attention worldwide owing to their many health benefits. Nuclear magnetic resonance (NMR) was utilized for the metabolite fingerprinting of 4 major legume sprouts, belonging to family Fabaceae, to be exploited for quality control purposes. Thirty-two metabolites were identified belonging to different classes, i.e., fatty acids, sugars, amino acids, nucleobases, organic acids, sterols, alkaloids, and isoflavonoids. Quantitative NMR was employed for assessing the major identified metabolite levels and multivariate data analysis was utilized to assess metabolome heterogeneity among sprout samples. Isoflavones were detected exclusively in Cicer sprouts, whereas Trigonella was characterized by 4-hydroxyisoleucine. Vicia sprouts were distinguished from other legume sprouts by the presence of L-Dopa versus acetate abundance in Lens. A common alkaloid in all sprouts was trigonelline, detected at 8–25 µg/mg, suggesting its potential role in legume seeds’ germination. Trigonelline was found at highest levels in Trigonella sprouts. The aromatic NMR region data (δ 11.0–5.0 ppm) provided a better classification power than the full range (δ 11.0–0.0 ppm) as sprout variations mostly originated from secondary metabolites, which can serve as chemotaxonomic markers. A2 - C1 - Bioorganic Chemistry ER - TY - JOUR ID - 435 TI - Anthelmintic activity and cytotoxic effects of compounds isolated from the fruits of Ozoroa insignis Del. (Anacardiaceae) JO - Biomolecules PY - 2021 SP - 1893 AU - Dube, M. AU - Saoud, M. AU - Rennert, R. AU - Fotso, G. W. AU - Andrae-Marobela, K. AU - Imming, P. AU - Häberli, C. AU - Keiser, J. AU - Arnold, N. AU - VL - 11 UR - https://doi.org/10.3390/biom11121893 DO - 10.3390/biom11121893 AB - Ozoroa insignis Del. is an ethnobotanical plant widely used in traditional medicine for various ailments, including schistosomiasis, tapeworm, and hookworm infections. From the so far not investigated fruits of Ozoroa insignis, the anthelmintic principles could be isolated through bioassay-guided isolation using Caenorhabditis elegans and identified by NMR spectroscopic analysis and mass spectrometric studies. Isolated 6-[8(Z)-pentadecenyl] anacardic (1), 6-[10(Z)-heptadecenyl] anacardic acid (2), and 3-[7(Z)-pentadecenyl] phenol (3) were evaluated against the 5 parasitic organisms Schistosoma mansoni (adult and newly transformed schistosomula), Strongyloides ratti, Heligmosomoides polygyrus, Necator americanus, and Ancylostoma ceylanicum, which mainly infect humans and other mammals. Compounds 1–3 showed good activity against Schistosoma mansoni, with compound 1 showing the best activity against newly transformed schistosomula with 50% activity at 1µM. The isolated compounds were also evaluated for their cytotoxic properties against PC-3 (human prostate adenocarcinoma) and HT-29 (human colorectal adenocarcinoma) cell lines, whereby compounds 2 and 3 showed antiproliferative activity in both cancer cell lines, while compound 1 exhibited antiproliferative activity only on PC-3 cells. With an IC50 value of 43.2 µM, compound 3 was found to be the most active of the 3 investigated compounds. A2 - C1 - Bioorganic Chemistry ER - TY - JOUR ID - 434 TI - Antitumor potential of cisplatin loaded into SBA-15 mesoporous silica nanoparticles against B16F1 melanoma cells: in vitro and in vivo studies JO - J. Inorg. Biochem. PY - 2021 SP - 111383 AU - Drača, D. AU - Edeler, D. AU - Saoud, M. AU - Dojčinović, B. AU - Dunđerović, D. AU - Đmura, G. AU - Maksimović-Ivanić, D. AU - Mijatović, S. AU - Kaluđerović, G. N. AU - VL - 217 UR - https://doi.org/10.1016/j.jinorgbio.2021.111383 DO - 10.1016/j.jinorgbio.2021.111383 AB - CP (cisplatin) and mesoporous silica SBA-15 (Santa Barbara amorphous 15) loaded with CP (→SBA-15|CP) were tested in vitro and in vivo against low metastatic mouse melanoma B16F1 cell line. SBA-15 only, as drug carrier, is found to be not active, while CP and SBA-15|CP revealed high cytotoxicity in lower μM range. The activity of SBA-15|CP was found similar to the activity of CP alone. Both CP and SBA-15|CP induced inhibition of cell proliferation (carboxyfluorescein succinimidyl ester - CFSE assay) along with G2/M arrest (4′,6-diamidino-2-phenylindole - DAPI assay). Apoptosis (Annexin V/ propidium iodide - PI assay), through caspase activation (apostat assay) and nitric oxide (NO) production (diacetate(4-amino-5-methylamino-2′,7′-difluorofluorescein-diacetat) - DAF FM assay), was identified as main mode of cell death. However, slight elevated autophagy (acridine orange - AO assay) was detected in treated B16F1 cells. CP and SBA-15|CP did not affect production of ROS (reactive oxygen species) in B16F1 cells. Both SBA-15|CP and CP induced in B16F1 G2 arrest and subsequent senescence. SBA-15|CP, but not CP, blocked the growth of melanoma in C57BL/6 mice. Moreover, hepato- and nephrotoxicity in SBA-15|CP treated animals were diminished in comparison to CP confirming multiply improved antitumor potential of immobilized CP. Outstandingly, SBA-15 boosted in vivo activity and diminished side effects of CP. A2 - C1 - Bioorganic Chemistry ER - TY - JOUR ID - 432 TI - Synthesis and biological evaluation of highly potent fungicidal deoxy‐hygrophorones JO - Eur. J. Org. Chem. PY - 2021 SP - 3827-3836 AU - Ditfe, T. AU - Bette, E. AU - N. Sultani, H. AU - Otto, A. AU - Wessjohann, L. A. AU - Arnold, N. AU - Westermann, B. AU - VL - 2021 UR - https://chemistry-europe.onlinelibrary.wiley.com/doi/full/10.1002/ejoc.202100729 DO - 10.1002/ejoc.202100729 AB - Although stripped from hydroxyl-groups, deoxygenated hygrophorones remain highly active against severe phytopathogens. The synthesis to these natural product congeners is achieved in rearrangement sequences, with an optimized deprotection strategy avoiding retro-aldol reactions. The activities are comparable to fungicides used in agriculture. Based on naturally occurring hygrophorones, racemic di- and mono-hydroxylated cyclopentenones bearing an aliphatic side chain have been produced in short synthetic sequences starting from furfuryl aldehyde. For the series of dihydroxylated trans-configured derivatives, an Achmatowicz-rearrangement and a Caddick-ring contraction were employed, and for the series of trans-configured mono-hydroxylated derivatives a Piancatelli-rearrangement. All final products showed good to excellent fungicidal activities against the plant pathogens B. cinerea, S. tritici and P. infestans. A2 - C1 - Bioorganic Chemistry ER - TY - JOUR ID - 431 TI - Role of ABCA7 in human health and in alzheimer’s disease JO - Int. J. Mol. Sci. PY - 2021 SP - 4603 AU - Dib, S. AU - Pahnke, J. AU - Gosselet, F. AU - VL - 22 UR - https://doi.org/10.3390/ijms22094603 DO - 10.3390/ijms22094603 AB - Several studies, including genome wide association studies (GWAS), have strongly suggested a central role for the ATP-binding cassette transporter subfamily A member 7 (ABCA7) in Alzheimer’s disease (AD). This ABC transporter is now considered as an important genetic determinant for late onset Alzheimer disease (LOAD) by regulating several molecular processes such as cholesterol metabolism and amyloid processing and clearance. In this review we shed light on these new functions and their cross-talk, explaining its implication in brain functioning, and therefore in AD onset and development. A2 - C1 - Bioorganic Chemistry ER - TY - JOUR ID - 511 TI - Access to new cytotoxic triterpene and steroidal Acid-TEMPO Conjugates by ugi multicomponent-reactions JO - Int. J. Mol. Sci. PY - 2021 SP - 7125 AU - Sultani, H. N. AU - Morgan, I. AU - Hussain, H. AU - Roos, A. H. AU - Haeri, H. H. AU - Kaluđerović, G. N. AU - Hinderberger, D. AU - Westermann, B. AU - VL - 22 UR - https://doi.org/10.3390/ijms22137125 DO - 10.3390/ijms22137125 AB - Multicomponent reactions, especially the Ugi-four component reaction (U-4CR), provide powerful protocols to efficiently access compounds having potent biological and pharmacological effects. Thus, a diverse library of betulinic acid (BA), fusidic acid (FA), cholic acid (CA) conjugates with TEMPO (nitroxide) have been prepared using this approach, which also makes them applicable in electron paramagnetic resonance (EPR) spectroscopy. Moreover, convertible amide modified spin-labelled fusidic acid derivatives were selected for post-Ugi modification utilizing a wide range of reaction conditions which kept the paramagnetic center intact. The nitroxide labelled betulinic acid analogue 6 possesses cytotoxic effects towards two investigated cell lines: prostate cancer PC3 (IC50 7.4 ± 0.7 μM) and colon cancer HT29 (IC50 9.0 ± 0.4 μM). Notably, spin-labelled fusidic acid derivative 8 acts strongly against these two cancer cell lines (PC3: IC50 6.0 ± 1.1 μM; HT29: IC50 7.4 ± 0.6 μM). Additionally, another fusidic acid analogue 9 was also found to be active towards HT29 with IC50 7.0 ± 0.3 μM (CV). Studies on the mode of action revealed that compound 8 increased the level of caspase-3 significantly which clearly indicates induction of apoptosis by activation of the caspase pathway. Furthermore, the exclusive mitochondria targeting of compound 18 was successfully achieved, since mitochondria are the major source of ROS generation. A2 - C1 - Bioorganic Chemistry ER - TY - JOUR ID - 509 TI - Transition from seeds to seedlings: Hormonal and epigenetic aspects JO - Plants PY - 2021 SP - 1884 AU - Smolikova, G. AU - Strygina, K. AU - Krylova, E. AU - Leonova, T. AU - Frolov, A. AU - Khlestkina, E. AU - Medvedev, S. AU - VL - 10 UR - https://doi.org/10.3390/plants10091884 DO - 10.3390/plants10091884 AB - Transition from seed to seedling is one of the critical developmental steps, dramatically affecting plant growth and viability. Before plants enter the vegetative phase of their ontogenesis, massive rearrangements of signaling pathways and switching of gene expression programs are required. This results in suppression of the genes controlling seed maturation and activation of those involved in regulation of vegetative growth. At the level of hormonal regulation, these events are controlled by the balance of abscisic acid and gibberellins, although ethylene, auxins, brassinosteroids, cytokinins, and jasmonates are also involved. The key players include the members of the LAFL network—the transcription factors LEAFY COTYLEDON1 and 2 (LEC 1 and 2), ABSCISIC ACID INSENSITIVE3 (ABI3), and FUSCA3 (FUS3), as well as DELAY OF GERMINATION1 (DOG1). They are the negative regulators of seed germination and need to be suppressed before seedling development can be initiated. This repressive signal is mediated by chromatin remodeling complexes—POLYCOMB REPRESSIVE COMPLEX 1 and 2 (PRC1 and PRC2), as well as PICKLE (PKL) and PICKLE-RELATED2 (PKR2) proteins. Finally, epigenetic methylation of cytosine residues in DNA, histone post-translational modifications, and post-transcriptional downregulation of seed maturation genes with miRNA are discussed. Here, we summarize recent updates in the study of hormonal and epigenetic switches involved in regulation of the transition from seed germination to the post-germination stage. A2 - C1 - Bioorganic Chemistry ER - TY - JOUR ID - 508 TI - Desiccation tolerance as the basis of long-term seed viability JO - Int. J. Mol. Sci. PY - 2021 SP - 101 AU - Smolikova, G. AU - Leonova, T. AU - Vashurina, N. AU - Frolov, A. AU - Medvedev, S. AU - VL - 22 UR - https://www.mdpi.com/1422-0067/22/1/101 DO - 10.3390/ijms22010101 AB - Desiccation tolerance appeared as the key adaptation feature of photoautotrophic organisms for survival in terrestrial habitats. During the further evolution, vascular plants developed complex anatomy structures and molecular mechanisms to maintain the hydrated state of cell environment and sustain dehydration. However, the role of the genes encoding the mechanisms behind this adaptive feature of terrestrial plants changed with their evolution. Thus, in higher vascular plants it is restricted to protection of spores, seeds and pollen from dehydration, whereas the mature vegetative stages became sensitive to desiccation. During maturation, orthodox seeds lose up to 95% of water and successfully enter dormancy. This feature allows seeds maintaining their viability even under strongly fluctuating environmental conditions. The mechanisms behind the desiccation tolerance are activated at the late seed maturation stage and are associated with the accumulation of late embryogenesis abundant (LEA) proteins, small heat shock proteins (sHSP), non-reducing oligosaccharides, and antioxidants of different chemical nature. The main regulators of maturation and desiccation tolerance are abscisic acid and protein DOG1, which control the network of transcription factors, represented by LEC1, LEC2, FUS3, ABI3, ABI5, AGL67, PLATZ1, PLATZ2. This network is complemented by epigenetic regulation of gene expression via methylation of DNA, post-translational modifications of histones and chromatin remodeling. These fine regulatory mechanisms allow orthodox seeds maintaining desiccation tolerance during the whole period of germination up to the stage of radicle protrusion. This time point, in which seeds lose desiccation tolerance, is critical for the whole process of seed development. A2 - C1 - Bioorganic Chemistry ER - TY - JOUR ID - 499 TI - Metabolism of photosynthetic organisms JO - Life PY - 2021 SP - 946 AU - Savchenko, T. AU - Frolov, A. AU - VL - 11 UR - https://doi.org/10.3390/life11090946 DO - 10.3390/life11090946 AB - A2 - C1 - Bioorganic Chemistry ER - TY - JOUR ID - 478 TI - pH-responsive release of ruthenium metallotherapeutics from mesoporous silica-based nanocarriers JO - Pharmaceutics PY - 2021 SP - 460 AU - Mladenović, M. AU - Morgan, I. AU - Ilić, N. AU - Saoud, M. AU - Pergal, M. V. AU - Kaluderović, G. N. AU - Knežević, N. ?. AU - VL - 13 UR - https://www.mdpi.com/1999-4923/13/4/460 DO - 10.3390/pharmaceutics13040460 AB - Ruthenium complexes are attracting interest in cancer treatment due to their potent cytotoxic activity. However, as their high toxicity may also affect healthy tissues, efficient and selective drug delivery systems to tumour tissues are needed. Our study focuses on the construction of such drug delivery systems for the delivery of cytotoxic Ru(II) complexes upon exposure to a weakly acidic environment of tumours. As nanocarriers, mesoporous silica nanoparticles (MSN) are utilized, whose surface is functionalized with two types of ligands, (2-thienylmethyl)hydrazine hydrochloride (H1) and (5,6-dimethylthieno[2,3-d]pyrimidin-4-yl)hydrazine (H2), which were attached to MSN through a pH-responsive hydrazone linkage. Further coordination to ruthenium(II) center yielded two types of nanomaterials MSN-H1[Ru] and MSN-H2[Ru]. Spectrophotometric measurements of the drug release kinetics at different pH (5.0, 6.0 and 7.4) confirm the enhanced release of Ru(II) complexes at lower pH values, which is further supported by inductively coupled plasma optical emission spectrometry (ICP-OES) measurements. Furthermore, the cytotoxicity effect of the released metallotherapeutics is evaluated in vitro on metastatic B16F1 melanoma cells and enhanced cancer cell-killing efficacy is demonstrated upon exposure of the nanomaterials to weakly acidic conditions. The obtained results showcase the promising capabilities of the designed MSN nanocarriers for the pH-responsive delivery of metallotherapeutics and targeted treatment of cancer. A2 - C1 - Bioorganic Chemistry ER - TY - JOUR ID - 472 TI - Analysis of Unusual Sulfated Constituents and Anti-infective Properties of Two Indonesian Mangroves, Lumnitzera littorea and Lumnitzera racemosa (Combretaceae) JO - Separations PY - 2021 SP - 82 AU - Manurung, J. AU - Kappen, J. AU - Schnitzler, J. AU - Frolov, A. AU - Wessjohann, L. A. AU - Agusta, A. AU - Muellner-Riehl, A. N. AU - Franke, K. AU - VL - 8 UR - https://www.mdpi.com/2297-8739/8/6/82 DO - 10.3390/separations8060082 AB - Lumnitzera littorea and Lumnitzera racemosa are mangrove species distributed widely along the Indonesian coasts. Besides their ecological importance, both are of interest owing to their wealth of natural products, some of which constitute potential sources for medicinal applications. We aimed to discover and characterize new anti-infective compounds, based on population-level sampling of both species from across the Indonesian Archipelago. Root metabolites were investigated by TLC, hyphenated LC-MS/MS and isolation, the internal transcribed spacer (ITS) region of rDNA was used for genetic characterization. Phytochemical characterization of both species revealed an unusual diversity in sulfated constituents with 3,3’,4’-tri-O-methyl-ellagic acid 4-sulfate representing the major compound in most samples. None of these compounds was previously reported for mangroves. Chemophenetic comparison of L. racemosa populations from different localities provided evolutionary information, as supported by molecular phylogenetic evidence. Samples of both species from particular locations exhibited anti-bacterial potential (Southern Nias Island and East Java against Gram-negative bacteria, Halmahera and Ternate Island against Gram-positive bacteria). In conclusion, Lumnitzera roots from natural mangrove stands represent a promising source for sulfated ellagic acid derivatives and further sulfur containing plant metabolites with potential human health benefits. A2 - C1 - Bioorganic Chemistry ER - TY - JOUR ID - 469 TI - Bruceadysentoside A, a new pregnane glycoside and others secondary metabolites with cytotoxic activity from brucea antidysenterica J. F. Mill. (simaroubaceae) JO - Nat. Prod. Res. PY - 2021 SP - 2037-2043 AU - Makong, Y. S. AU - Fotso, G. W. AU - Mouthe, G. H. AU - Lenta, B. AU - Rennert, R. AU - Sewald, N. AU - Arnold, N. AU - Wansi, J. D. AU - Ngadjui, B. T. AU - VL - 35 UR - https://doi.org/10.1080/14786419.2019.1655024 DO - 10.1080/14786419.2019.1655024 AB - The chemical investigation of the root barks leaves and stem barks of Brucea antidysenterica J. F. Mill. (Simaroubaceae) led to the isolation of a new pregnane glycoside, named Bruceadysentoside A or 3-O-β-L-arabinopyranosyl-pregn-5-en-20-one (1) together with seventeen known compounds. Their structures were established from spectral data, mainly HRESIMS, 1 D and 2 D NMR and by comparison with literature data. Compounds 1, 2, 5, 6, 8, 10, 12 and 13 were tested in vitro for their effects on the viability of two different human cancer cell lines, namely prostate PC-3 adenocarcinoma cells and colorectal HT-29 adenocarcinoma cells. No substantial activities were recorded for 2, 10, 12 and 13 (up to 10 μM concentration). 1, 5 and 8 did not show strong anti-proliferative effects up to 100 μM, however, 6 exhibited a stronger anti-proliferative effect with IC50 values of ∼ 100 μM against PC-3 and ∼ 200 μM against HT-29. A2 - C1 - Bioorganic Chemistry ER - TY - JOUR ID - 456 TI - Fluorescent spherical mesoporous silica nanoparticles loaded with emodin: Synthesis, cellular uptake and anticancer activity JO - Mater. Sci. Eng. C-Mater. Biol. Appl. PY - 2021 SP - 111619 AU - Jänicke, P. AU - Lennicke, C. AU - Meister, A. AU - Seliger, B. AU - Wessjohann, L. A. AU - Kaluđerović, G. N. AU - VL - 119 UR - https://doi.org/10.1016/j.msec.2020.111619 DO - 10.1016/j.msec.2020.111619 AB - The natural product emodin (EO) exhibits anti-inflammatory, antiangiogenesis and antineoplastic properties in vitro and in vivo. Due to its biological properties as well as its fluorescence, EO can be useful in pharmacology and pharmacokinetics. To enhance its selectivity to cancer cells, EO was loaded into non-fluorescent and novel fluorescent spherical mesoporous nanoparticles bearing N-methyl isatoic anhydride (SNM~M) or lissamine rhodamine B sulfonyl moieties (SNM~L). The propylamine functionalized mesoporous silica nanomaterial (SNM) were characterized by powder X-ray diffraction (XRD), nitrogen gas sorption, scanning electron microscopy (SEM), transmission electron microscopy (TEM), fluorescence spectroscopy, thermogravimetric analysis (TGA) and UV spectroscopy. The cytotoxicity of EO-loaded nanoparticles was tested against the human colon carcinoma cell line HT-29. Non-loaded SNM did not affect cell proliferation, whereas those loaded with EO were at least as efficient as EO alone. It could be shown by fluorescence microscopy that the uptake of silica nanomaterial by the tumor cells occurred within 2 h and the release of EO occurred within 48 h of treatment. Flow cytometry and Western blot analysis showed that SNM containing EO induced apoptosis in HT-29 cells. A2 - C1 - Bioorganic Chemistry ER - TY - JOUR ID - 495 TI - Total synthesis of Aetokthonotoxin, the cyanobacterial neurotoxin causing vacuolar myelinopathy JO - Chem.-Eur. J. PY - 2021 SP - 12032-12035 AU - Ricardo, M. G. AU - Schwark, M. AU - Llanes, D. AU - Niedermeyer, T. H. J. AU - Westermann, B. AU - VL - 27 UR - https://doi.org/10.1002/chem.202101848 DO - 10.1002/chem.202101848 AB - Aetokthonotoxin has recently been identified as the cyanobacterial neurotoxin causing Vacuolar Myelinopathy, a fatal neurologic disease, spreading through a trophic cascade and affecting birds of prey such as the bald eagle in the USA. Here, we describe the total synthesis of this specialized metabolite. The complex, highly brominated 1,2’-biindole could be synthesized via a Somei-type Michael reaction as key step. The optimised sequence yielded the natural product in five steps with an overall yield of 29 %. A2 - C1 - Bioorganic Chemistry ER - TY - JOUR ID - 487 TI - In Vitro Evaluation of Antiproliferative Properties of Novel Organotin(IV) Carboxylate Compounds with Propanoic Acid Derivatives on a Panel of Human Cancer Cell Lines JO - Molecules PY - 2021 SP - 3199 AU - Pantelić, N. ?. AU - Božić, B. AU - Zmejkovski, B. B. AU - Banjac, N. R. AU - Dojčinović, B. AU - Wessjohann, L. A. AU - Kaluđerović, G. N. AU - VL - 26 UR - https://www.mdpi.com/1420-3049/26/11/3199 DO - 10.3390/molecules26113199 AB - The synthesis of novel triphenyltin(IV) compounds, Ph3SnLn (n = 1–3), with oxaprozin (3-(4,5-diphenyloxazol-2-yl)propanoic acid), HL1, and the new propanoic acid derivatives 3-(4,5-bis(4-methoxylphenyl)oxazol-2-yl)propanoic acid, HL2, and 3-(2,5-dioxo-4,4-diphenylimidazolidin-1-yl)propanoic acid, HL3, has been performed. The ligands represent commercial drugs or their derivatives and the tin complexes have been characterized by standard analytical methods. The in vitro antiproliferative activity of both ligands and organotin(IV) compounds has been evaluated on the following tumour cell lines: human prostate cancer (PC-3), human colorectal adenocarcinoma (HT-29), breast cancer (MCF-7), and hepatocellular cancer (HepG2), as well as on normal mouse embryonic fibroblast cells (NIH3T3) with the aid of MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-12 diphenyltetrazolium bromide) and CV (crystal violet) assays. Contrary to the inactive ligand precursors, all organotin(IV) carboxylates showed very good activity with IC50 values ranging from 0.100 to 0.758 µM. According to the CV assay (IC50 = 0.218 ± 0.025 µM), complex Ph3SnL1 demonstrated the highest cytotoxicity against the caspase 3 deficient MCF-7 cell line. Inductively coupled plasma mass spectrometry (ICP-MS) analysis indicated a two-fold lower concentration of tin in MCF-7 cells in comparison to platinum. To investigate the mechanism of action of the compound Ph3SnL1 on MCF-7 cells, morphological, autophagy and cell cycle analysis, as well as the activation of caspase and ROS/RNS and NO production, has been performed. Results suggest that Ph3SnL1 induces caspase-independent apoptosis in MCF-7 cells. A2 - C1 - Bioorganic Chemistry ER - TY - JOUR ID - 484 TI - Computational Applications in Secondary Metabolite Discovery (CAiSMD): an online workshop JO - J. Cheminform. PY - 2021 SP - 64 AU - Ntie-Kang, F. AU - Telukunta, K. K. AU - Fobofou, S. A. T. AU - Chukwudi Osamor, V. AU - Egieyeh, S. A. AU - Valli, M. AU - Djoumbou-Feunang, Y. AU - Sorokina, M. AU - Stork, C. AU - Mathai, N. AU - Zierep, P. AU - Chávez-Hernández, A. L. AU - Duran-Frigola, M. AU - Babiaka, S. B. AU - Tematio Fouedjou, R. AU - Eni, D. B. AU - Akame, S. AU - Arreyetta-Bawak, A. B. AU - Ebob, O. T. AU - Metuge, J. A. AU - Bekono, B. D. AU - Isa, M. A. AU - Onuku, R. AU - Shadrack, D. M. AU - Musyoka, T. M. AU - Patil, V. M. AU - van der Hooft, J. J. J. AU - da Silva Bolzani, V. AU - Medina-Franco, J. L. AU - Kirchmair, J. AU - Weber, T. AU - Tastan Bishop, ?. AU - Medema, M. H. AU - Wessjohann, L. A. AU - Ludwig-Müller, J. AU - VL - 13 UR - https://doi.org/10.1186/s13321‑021‑00546‑8 DO - 10.1186/s13321-021-00546-8 AB - AbstractWe report the major conclusions of the online open-access workshop “Computational Applications in Secondary Metabolite Discovery (CAiSMD)” that took place from 08 to 10 March 2021. Invited speakers from academia and industry and about 200 registered participants from five continents (Africa, Asia, Europe, South America, and North America) took part in the workshop. The workshop highlighted the potential applications of computational methodologies in the search for secondary metabolites (SMs) or natural products (NPs) as potential drugs and drug leads. During 3 days, the participants of this online workshop received an overview of modern computer-based approaches for exploring NP discovery in the “omics” age. The invited experts gave keynote lectures, trained participants in hands-on sessions, and held round table discussions. This was followed by oral presentations with much interaction between the speakers and the audience. Selected applicants (early-career scientists) were offered the opportunity to give oral presentations (15 min) and present posters in the form of flash presentations (5 min) upon submission of an abstract. The final program available on the workshop website (https://caismd.indiayouth.info/) comprised of 4 keynote lectures (KLs), 12 oral presentations (OPs), 2 round table discussions (RTDs), and 5 hands-on sessions (HSs). This meeting report also references internet resources for computational biology in the area of secondary metabolites that are of use outside of the workshop areas and will constitute a long-term valuable source for the community. The workshop concluded with an online survey form to be completed by speakers and participants for the goal of improving any subsequent editions. A2 - C1 - Bioorganic Chemistry ER - TY - JOUR ID - 481 TI - C@PA: Computer-aided pattern analysis to predict multitarget ABC transporter inhibitors JO - J. Med. Chem. PY - 2021 SP - 3350-3366 AU - Namasivayam, V. AU - Silbermann, K. AU - Wiese, M. AU - Pahnke, J. AU - Stefan, S. M. AU - VL - 64 UR - DO - 10.1021/acs.jmedchem.0c02199 AB - Based on literature reports of the last two decades, a computer-aided pattern analysis (C@PA) was implemented for the discovery of novel multitarget ABCB1 (P-gp), ABCC1 (MRP1), and ABCG2 (BCRP) inhibitors. C@PA included basic scaffold identification, substructure search and statistical distribution, as well as novel scaffold extraction to screen a large virtual compound library. Over 45,000 putative and novel broad-spectrum ABC transporter inhibitors were identified, from which 23 were purchased for biological evaluation. Our investigations revealed five novel lead molecules as triple ABCB1, ABCC1, and ABCG2 inhibitors. C@PA is the very first successful computational approach for the discovery of promiscuous ABC transporter inhibitors. A2 - C1 - Bioorganic Chemistry ER - TY - CHAP ID - 12 TI - Individual glycation sites as biomarkers of Type 2 diabetes mellitus T2 - Type 2 Diabetes from Pathophysiology to Cyber Systems PB - IntechOpen PY - 2021 SP - AU - Soboleva, A. AU - Vashurina, N. AU - Frolov, A. AU - VL - UR - http://dx.doi.org/10.5772/intechopen.95532 SN - 978-1-83881-903-3 DO - 10.5772/intechopen.95532 AB - Type 2 diabetes mellitus (T2DM) is a widely spread metabolic disease, the initial stages of which are asymptomatic and have no clinically recognizable manifestation. At the molecular level, T2DM is manifested with essential non-enzymatic structural changes of intra- and extracellular proteins, mostly represented with oxidation and glycation of multiple residues. Protein glycation is one of the most universal markers of T2DM, and is recognized as an indirect, but adequate indicator of plasma glucose levels over prolonged periods of time. Unfortunately, glycated hemoglobin (HbA1c) – the universally accepted T2DM marker, is insensitive for short-term excursions of blood glucose, which are known to precede the onset of disease. Therefore, new generation biomarkers, giving access to the time dimension of Maillard reaction in blood, are desired. In this context, establishment of individual glycation sites of plasma proteins as new T2DM biomarkers might be a promising approach. Indeed, involvement of proteins with different half-life times in such analysis will make the time dimension of protein glycation in blood available and will allow early recognition of blood sugar fluctuations, occurring within few weeks or even days. A2 - Dr. Anca Pantea Stoian C1 - Bioorganic Chemistry ER - TY - JOUR ID - 618 TI - Measurement of cerebral ABCC1 transport activity in wild-type and APP/PS1-21 mice with positron emission tomography JO - J. Cereb. Blood Flow Metab. PY - 2020 SP - 954-965 AU - Zoufal, V. AU - Mairinger, S. AU - Krohn, M. AU - Wanek, T. AU - Filip, T. AU - Sauberer, M. AU - Stanek, J. AU - Kuntner, C. AU - Pahnke, J. AU - Langer, O. AU - VL - 40 UR - DO - 10.1177/0271678X19854541 AB - Previous data suggest a possible link between multidrug resistance-associated protein 1 (ABCC1) and brain clearance of beta-amyloid (Aβ). We used PET with 6-bromo-7-[11C]methylpurine ([11C]BMP) to measure cerebral ABCC1 transport activity in a beta-amyloidosis mouse model (APP/PS1-21) and in wild-type mice aged 50 and 170 days, without and with pretreatment with the ABCC1 inhibitor MK571. One hundred seventy days-old-animals additionally underwent [11C]PiB PET scans to measure Aβ load. While baseline [11C]BMP PET scans detected no differences in the elimination slope of radioactivity washout from the brain (kelim) between APP/PS1-21 and wild-type mice of both age groups, PET scans after MK571 pretreatment revealed significantly higher kelim values in APP/PS1-21 mice than in wild-type mice aged 170 days, suggesting increased ABCC1 activity. The observed increase in kelim occurred across all investigated brain regions and was independent of the presence of Aβ plaques measured with [11C]PiB. Western blot analysis revealed a trend towards increased whole brain ABCC1 levels in 170 days-old-APP/PS1-21 mice versus wild-type mice and a significant positive correlation between ABCC1 levels and kelim. Our data point to an upregulation of ABCC1 in APP/PS1-21 mice, which may be related to an induction of ABCC1 in astrocytes as a protective mechanism against oxidative stress. A2 - C1 - Bioorganic Chemistry ER - TY - JOUR ID - 617 TI - Imaging P-Glycoprotein Induction at the Blood–Brain Barrier of a β-Amyloidosis Mouse Model with 11C-Metoclopramide PET JO - J. Nucl. Med. PY - 2020 SP - 1050-1057 AU - Zoufal, V. AU - Mairinger, S. AU - Brackhan, M. AU - Krohn, M. AU - Filip, T. AU - Sauberer, M. AU - Stanek, J. AU - Wanek, T. AU - Tournier, N. AU - Bauer, M. AU - Pahnke, J. AU - Langer, O. AU - VL - 61 UR - https://doi.org/10.2967/jnumed.119.237198 DO - 10.2967/jnumed.119.237198 AB - P-glycoprotein (ABC subfamily B member 1, ABCB1) plays an important role at the blood-brain barrier (BBB) in promoting clearance of neurotoxic β-amyloid (Aβ) peptides from the brain into the blood. ABCB1 expression and activity were found to be decreased in the brains of Alzheimer disease patients. Treatment with drugs that induce cerebral ABCB1 activity may be a promising approach to delay the build-up of Aβ deposits in the brain by enhancing clearance of Aβ peptides from the brain. The aim of this study was to investigate whether PET with the weak ABCB1 substrate radiotracer 11C-metoclopramide can measure ABCB1 induction at the BBB in a β-amyloidosis mouse model (APP/PS1-21 mice) and in wild-type mice. Methods: Groups of wild-type and APP/PS1-21 mice aged 50 or 170 d underwent 11C-metoclopramide baseline PET scans or scans after intraperitoneal treatment with the rodent pregnane X receptor activator 5-pregnen-3β-ol-20-one-16α-carbonitrile (PCN, 25 mg/kg) or its vehicle over 7 d. At the end of the PET scans, brains were harvested for immunohistochemical analysis of ABCB1 and Aβ levels. In separate groups of mice, radiolabeled metabolites of 11C-metoclopramide were determined in plasma and brain at 15 min after radiotracer injection. As an outcome parameter of cerebral ABCB1 activity, the elimination slope of radioactivity washout from the brain (k E,brain) was calculated. Results: PCN treatment resulted in an increased clearance of radioactivity from the brain as reflected by significant increases in k E,brain (from +26% to +54% relative to baseline). Immunohistochemical analysis confirmed ABCB1 induction in the brains of PCN-treated APP/PS1-21 mice with a concomitant decrease in Aβ levels. There was a significant positive correlation between k E,brain and ABCB1 levels in the brain. In wild-type mice, a significant age-related decrease in k E,brain was found. Metabolite analysis showed that most radioactivity in the brain comprised unmetabolized 11C-metoclopramide in all animal groups. Conclusion: 11C-metoclopramide can measure ABCB1 induction in the mouse brain without the need to consider an arterial input function and may find potential application in Alzheimer disease patients to noninvasively evaluate strategies to enhance the clearance properties of the BBB. A2 - C1 - Bioorganic Chemistry ER - TY - JOUR ID - 616 TI - Age dependency of cerebral P-glycoprotein function in wild-type and APPPS1 mice measured with PET JO - J. Cereb. Blood Flow Metab. PY - 2020 SP - 150-162 AU - Zoufal, V. AU - Wanek, T. AU - Krohn, M. AU - Mairinger, S. AU - Filip, T. AU - Sauberer, M. AU - Stanek, J. AU - Pekar, T. AU - Bauer, M. AU - Pahnke, J. AU - Langer, O. AU - VL - 40 UR - DO - 10.1177/0271678X18806640 AB - P-glycoprotein (P-gp, ABCB1) is an efflux transporter at the blood–brain barrier (BBB), which mediates clearance of beta-amyloid (Aβ) from brain into blood. We used (R)-[11C]verapamil PET in combination with partial P-gp inhibition with tariquidar to measure cerebral P-gp function in a beta-amyloidosis mouse model (APPtg) and in control mice at three different ages (50, 200 and 380 days). Following tariquidar pre-treatment (4 mg/kg), whole brain-to-plasma radioactivity concentration ratios (Kp,brain) were significantly higher in APPtg than in wild-type mice aged 50 days, pointing to decreased cerebral P-gp function. Moreover, we found an age-dependent decrease in cerebral P-gp function in both wild-type and APPtg mice of up to −50%. Alterations in P-gp function were more pronounced in Aβ-rich brain regions (hippocampus, cortex) than in a control region with negligible Aβ load (cerebellum). PET results were confirmed by immunohistochemical staining of P-gp in brain microvessels. Our results confirm previous findings of reduced P-gp function in Alzheimer’s disease mouse models and show that our PET protocol possesses adequate sensitivity to measure these functional changes in vivo. Our PET protocol may find use in clinical studies to test the efficacy of drugs to induce P-gp function at the human BBB to enhance Aβ clearance. A2 - C1 - Bioorganic Chemistry ER - TY - JOUR ID - 603 TI - Mesomeric form of quaternary indoloquinazoline alkaloid and other constituents from the Cameroonian Rutaceae Araliopsis soyauxii Engl. JO - Biochem. Syst. Ecol. PY - 2020 SP - 104050 AU - Tchatchouang Noulala, C. G. AU - Fotso, G. W. AU - Rennert, R. AU - Lenta, B. N. AU - Sewald, N. AU - Arnold, N. AU - Happi, E. N. AU - Ngadjui, B. T. AU - VL - 91 UR - DO - 10.1016/j.bse.2020.104050 AB - A mesomeric form of quaternary indoloquinazoline alkaloid, soyauxinium chloride (1) was obtained through the chemical investigation of stem bark and roots of Araliopsis soyauxii Engl. [syn. Vepris soyauxii (Engl.) Mziray] (Rutaceae) together with fifteen known compounds, including three furoquinoline alkaloids, three 2-quinolones, two limonoids, two triterpenes, two steroids, a coumarin, an acridone alkaloid, and a flavonoid glycoside. Their structures were established by comprehensive spectroscopic and spectrometric analyses (1D and 2D NMR, ESI-HR-MS) and by comparison with previously reported data. 13C NMR data of araliopsinine are also reported here for the first time. The isolated compounds were screened in vitro for their effects on the viability of two different human cancer cell lines, namely prostate PC-3 adenocarcinoma cells and colorectal HT-29 adenocarcinoma cells. However, none of the tested compounds exhibited strong anti-proliferative or cytotoxic activities, to either prostate PC-3 cells or colon HT-29 cells. At 100 μM, the furoquinoline maculine showed a slightly increased anti-proliferative effect, however, exclusively on HT-29 cells. The chemotaxonomic significance of the isolated compounds has also been discussed. A2 - C1 - Bioorganic Chemistry ER - TY - JOUR ID - 601 TI - Phosphorylation‐dependent control of an RNA granule‐localized protein that fine‐tunes defence gene expression at a post‐transcriptional level JO - Plant J. PY - 2020 SP - 1023-1039 AU - Tabassum, N. AU - Eschen-Lippold, L. AU - Athmer, B. AU - Baruah, M. AU - Brode, M. AU - Maldonado-Bonilla, L. D. AU - Hoehenwarter, W. AU - Hause, G. AU - Scheel, D. AU - Lee, J. AU - VL - 101 UR - DO - 10.1111/tpj.14573 AB - Mitogen‐activated protein kinase (MAPK) cascades are key signalling modules of plant defence responses to pathogen‐associated molecular patterns (PAMPs, e.g. bacterial flg22 peptide). The Tandem Zinc Finger Protein 9 (TZF9) is an RNA‐binding protein that is phosphorylated by two PAMP‐responsive MAPKs, MPK3 and MPK6. We mapped the major phosphosites in TZF9 and showed their importance for controlling in vitro RNA‐binding activity, in vivo flg22‐induced rapid disappearance of TZF9‐labelled processing body‐like structures and TZF9 protein turnover. Microarray analysis showed a strong discordance between transcriptome (total mRNA) and translatome (polysome‐associated mRNA) in the tzf9 mutant, with more mRNAs associated to ribosomes in the absence of TZF9. This suggests that TZF9 may sequester and inhibit translation of subsets of mRNAs. Fittingly, TZF9 physically interacts with poly(A)‐binding protein 2 (PAB2), a hallmark constituent of stress granules – a site for stress‐induced translational stalling/arrest. TZF9 even promotes stress granule assembly in the absence of stress. Hence, MAPKs may control defence gene expression post‐transcriptionally through release from translation arrest within TZF9‐PAB2‐containing RNA granules or perturbing PAB2 functions in translation control (e.g. in the mRNA closed‐loop model of translation). A2 - C1 - Bioorganic Chemistry; Biochemistry of Plant Interactions; Cell and Metabolic Biology ER - TY - JOUR ID - 598 TI - Vesicular ATP-binding cassette transporters in human disease: relevant aspects of their organization for future drug development JO - Future Drug Discovery PY - 2020 SP - FDD51 AU - Stefan, K. AU - Wen Leck, L. Y. AU - Namasivayam, V. AU - Bascuñana, P. AU - Huang, M. L.-H. AU - Riss, P. J. AU - Pahnke, J. AU - Jansson, P. J. AU - Stefan, S. M. AU - VL - 4 UR - DO - 10.4155/fdd-2020-0025 AB - A2 - C1 - Bioorganic Chemistry ER - TY - JOUR ID - 597 TI - PSYCHE—A Valuable Experiment in Plant NMR-Metabolomics JO - Molecules PY - 2020 SP - 5125 AU - Stark, P. AU - Zab, C. AU - Porzel, A. AU - Franke, K. AU - Rizzo, P. AU - Wessjohann, L. A. AU - VL - 25 UR - https://doi.org/10.3390/molecules25215125 DO - 10.3390/molecules25215125 AB - 1H-NMR is a very reproducible spectroscopic method and, therefore, a powerful tool for the metabolomic analysis of biological samples. However, due to the high complexity of natural samples, such as plant extracts, the evaluation of spectra is difficult because of signal overlap. The new NMR “Pure Shift” methods improve spectral resolution by suppressing homonuclear coupling and turning multiplets into singlets. The PSYCHE (Pure Shift yielded by Chirp excitation) and the Zangger–Sterk pulse sequence were tested. The parameters of the more suitable PSYCHE experiment were optimized, and the extracts of 21 Hypericum species were measured. Different evaluation criteria were used to compare the suitability of the PSYCHE experiment with conventional 1H-NMR. The relationship between the integral of a signal and the related bin value established by linear regression demonstrates an equal representation of the integrals in binned PSYCHE spectra compared to conventional 1H-NMR. Using multivariate data analysis based on both techniques reveals comparable results. The obtained data demonstrate that Pure Shift spectra can support the evaluation of conventional 1H-NMR experiments. A2 - C1 - Bioorganic Chemistry ER - TY - JOUR ID - 596 TI - Two isostructural Co(II) flufenamato and niflumato complexes with bathocuproine: Analogues with a different cytotoxic activity JO - J. Inorg. Biochem. PY - 2020 SP - 111160 AU - Smolko, L. AU - Smolková, R. AU - Samoľová, E. AU - Morgan, I. AU - Saoud, M. AU - Kaluđerović, G. N. AU - VL - 210 UR - https://doi.org/10.1016/j.jinorgbio.2020.111160 DO - 10.1016/j.jinorgbio.2020.111160 AB - Two novel Co(II) fenamato complexes containing bathocuproine (bcp), namely [Co(bcp)(flu)2] (1) and [Co(bcp)(nif)2] (2) (flu = flufenamato, nif = niflumato) were synthesized and characterized by elemental analysis, single-crystal X-ray structure analysis as well as absorption and fluorescence spectroscopy. Investigation of their molecular structure revealed that both complexes are isostructural and form analogous complex molecules, with a Co(II) atom hexacoordinated by two nitrogen atoms of bcp and four oxygen atoms of two chelate bonded flu (1) and nif (2) ligands in a distorted octahedral arrangement. Surprisingly, the results of cytotoxicity experiments on four cancer cell lines (HeLa, HT-29, PC-3 and MCF-7) have revealed that despite similar structure of the complexes, the nif complex exhibits significantly higher activity, being the most effective against the PC-3 cell line (IC50 (MTT) = 6.11 ± 1.95 μM). Further studies performed on PC-3 cell line have shown that the mechanism of the cytotoxic action of nif complex (2) might involve activation of autophagic processes and apoptosis, while for its flu analogue (1) apoptosis was detected. A2 - C1 - Bioorganic Chemistry ER - TY - JOUR ID - 595 TI - Comparative analysis of the plastid conversion, photochemical activity and chlorophyll degradation in developing embryos of green-seeded and yellow-seeded pea (Pisum sativum) cultivars JO - Funct. Plant Biol. PY - 2020 SP - 409-424 AU - Smolikova, G. AU - Shiroglazova, O. AU - Vinogradova, G. AU - Leppyanen, I. AU - Dinastiya, E. AU - Yakovleva, O. AU - Dolgikh, E. AU - Titova, G. AU - Frolov, A. AU - Medvedev, S. AU - VL - 47 UR - DO - 10.1071/FP19270 AB - Developing seeds of some higher plants are photosynthetically active and contain chlorophylls (Chl), which are typically destroyed at the late stages of seed maturation. However, in some crop plant cultivars, degradation of embryonic Chl remains incomplete, and mature seeds preserve green colour, as it is known for green-seeded cultivars of pea (Pisum sativum L.). The residual Chl compromise seed quality and represent a severe challenge for farmers. Hence, comprehensive understanding of the molecular mechanisms, underlying incomplete Chl degradation is required for maintaining sustainable agriculture. Therefore, here we address dynamics of plastid conversion and photochemical activity alterations, accompanying degradation of Chl in embryos of yellow- and green-seeded cultivars Frisson and Rondo respectively. The yellow-seeded cultivar demonstrated higher rate of Chl degradation at later maturation stage, accompanied with termination of photochemical activity, seed dehydration and conversion of green plastids into amyloplasts. In agreement with this, expression of genes encoding enzymes of Chl degradation was lower in the green seeded cultivar, with the major differences in the levels of Chl b reductase (NYC1) and pheophytinase (PPH) transcripts. Thus, the difference between yellow and green seeds can be attributed to incomplete Chl degradation in the latter at the end of maturation period. A2 - C1 - Bioorganic Chemistry ER - TY - JOUR ID - 594 TI - Bringing new methods to the seed proteomics platform: Challenges and perspectives JO - Int. J. Mol. Sci. PY - 2020 SP - 9162 AU - Smolikova, G. AU - Gorbach, D. AU - Lukasheva, E. AU - Mavropolo-Stolyarenko, G. AU - Bilova, T. AU - Soboleva, A. AU - Tsarev, A. AU - Romanovskaya, E. AU - Podolskaya, E. AU - Zhukov, V. A. AU - Tikhonovich, I. AU - Medvedev, S. AU - Hoehenwarter, W. AU - Frolov, A. AU - VL - 21 UR - https://www.mdpi.com/1422-0067/21/23/9162 DO - 10.3390/ijms21239162 AB - For centuries, crop plants have represented the basis of the daily human diet. Among them, cereals and legumes, accumulating oils, proteins, and carbohydrates in their seeds, distinctly dominate modern agriculture, thus play an essential role in food industry and fuel production. Therefore, seeds of crop plants are intensively studied by food chemists, biologists, biochemists, and nutritional physiologists. Accordingly, seed development and germination as well as age- and stress-related alterations in seed vigor, longevity, nutritional value, and safety can be addressed by a broad panel of analytical, biochemical, and physiological methods. Currently, functional genomics is one of the most powerful tools, giving direct access to characteristic metabolic changes accompanying plant development, senescence, and response to biotic or abiotic stress. Among individual post-genomic methodological platforms, proteomics represents one of the most effective ones, giving access to cellular metabolism at the level of proteins. During the recent decades, multiple methodological advances were introduced in different branches of life science, although only some of them were established in seed proteomics so far. Therefore, here we discuss main methodological approaches already employed in seed proteomics, as well as those still waiting for implementation in this field of plant research, with a special emphasis on sample preparation, data acquisition, processing, and post-processing. Thereby, the overall goal of this review is to bring new methodologies emerging in different areas of proteomics research (clinical, food, ecological, microbial, and plant proteomics) to the broad society of seed biologists. A2 - C1 - Bioorganic Chemistry ER - TY - JOUR ID - 581 TI - Early Cognitive Training Rescues Remote Spatial Memory but Reduces Cognitive Flexibility in Alzheimer’s Disease Mice JO - J. Alzheimers Dis. PY - 2020 SP - 1301-1317 AU - Rai, S. P. AU - Krohn, M. AU - Pahnke, J. AU - VL - 75 UR - DO - 10.3233/JAD-200161 AB - Background:Spatial memory dysfunction has been demonstrated in mouse models of Alzheimer’s disease (AD) which is consistent with the clinical finding that the early signature of AD includes difficulties in the formation and/or storage of a memory. A stored memory—a long term memory—can be modulated via process called as memory retrieval that can either lead toward memory reconsolidation or even memory extinction.Objective:We aim to shed light on the fate of the spatial memory during memory reactivation and memory extinction using a water maze task.Methods:In Set-up I, we trained 3-month-old mice (wild-type mice and mice with cerebral β-amyloidosis) and assessed the fate of remote memory after four months of retention interval (RI). In Set-up II, we performed an early-extensive training at 2 months of age, retrained the same mice at 3 months of age, introduced four months of RI, and finally assessed remote spatial memory at 7 months of age.Results:We find in β-amyloidosis mice that memory reactivation problems were detectable at 7 months of age and were alleviated by cognitive overtraining. Similarly, forgetting of remote spatial memory was also minimized by cognitive overtraining. Finally, we show that the cognitive training facilitates the recovery of the reactivated spatial memory while reducing the ability to form new spatial memory in AD mice.Conclusion:This result may explain the rationality behind the cognitive reserve observed in AD patients and elderly with severe β-amyloidosis not corresponding to the actual low dementia symptoms. A2 - C1 - Bioorganic Chemistry ER - TY - JOUR ID - 580 TI - Detection and Prediction of Mild Cognitive Impairment in Alzheimer’s Disease Mice JO - J. Alzheimers Dis. PY - 2020 SP - 1209-1221 AU - Rai, S. P. AU - Bascuñana, P. AU - Brackhan, M. AU - Krohn, M. AU - Möhle, L. AU - Paarmann, K. AU - Pahnke, J. AU - VL - 77 UR - DO - 10.3233/jad-200675 AB - Background: The recent failure of clinical trials to treat Alzheimer’s disease (AD) indicates that the current approach of modifying disease is either wrong or is too late to be efficient. Mild cognitive impairment (MCI) denotes the phase between the preclinical phase and clinical overt dementia. AD mouse models that overexpress human amyloid-β (Aβ) are used to study disease pathogenesis and to conduct drug development/testing. However, there is no direct correlation between the Aβ deposition, the age of onset, and the severity of cognitive dysfunction. Objective: To detect and predict MCI when Aβ plaques start to appear in the hippocampus of an AD mouse. Methods: We trained wild-type and AD mice in a Morris water maze (WM) task with different inter-trial intervals (ITI) at 3 months of age and assessed their WM performance. Additionally, we used a classification algorithm to predict the genotype (APPtg versus wild-type) of an individual mouse from their respective WM data. Results: MCI can be empirically detected using a short-ITI protocol. We show that the ITI modulates the spatial learning of AD mice without affecting the formation of spatial memory. Finally, a simple classification algorithm such as logistic regression on WM data can give an accurate prediction of the cognitive dysfunction of a specific mouse. Conclusion: MCI can be detected as well as predicted simultaneously with the onset of Aβ deposition in the hippocampus in AD mouse model. The mild cognitive impairment prediction can be used for assessing the efficacy of a treatment. A2 - C1 - Bioorganic Chemistry ER - TY - JOUR ID - 578 TI - Synthesis, characterization and in vitro biological evaluation of novel organotin(IV) compounds with derivatives of 2-(5-arylidene-2,4-dioxothiazolidin-3-yl)propanoic acid JO - J. Inorg. Biochem. PY - 2020 SP - 111207 AU - Pantelić, N. ?. AU - Zmejkovski, B. B. AU - Božić, B. AU - Dojčinović, B. AU - Banjac, N. R. AU - Wessjohann, L. A. AU - Kaluđerović, G. N. AU - VL - 211 UR - https://doi.org/10.1016/j.jinorgbio.2020.111207 DO - 10.1016/j.jinorgbio.2020.111207 AB - Two novel triphenyltin(IV) compounds, [Ph3SnL1] (L1 = 2-(5-(4-fluorobenzylidene)-2,4-dioxotetrahydrothiazole-3-yl)propanoate (1)) and [Ph3SnL2] (L2 = 2-(5-(5-methyl-2-furfurylidene)-2,4-dioxotetrahydrothiazole-3-yl)propanoate (2)) were synthesized and characterized by FT-IR, (1H and 13C) NMR spectroscopy, mass spectrometry, and elemental microanalysis. The in vitro anticancer activity of the synthesized organotin(IV) compounds was determined against four tumor cell lines: PC-3 (prostate), HT-29 (colon), MCF-7 (breast), and HepG2 (hepatic) using MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-12 diphenyltetrazolium bromide) and CV (crystal violet) assays. The IC50 values are found to be in the range from 0.11 to 0.50 μM. Compound 1 exhibits the highest activity toward PC-3 cells (IC50 = 0.115 ± 0.009 μM; CV assay). The tin and platinum uptake in PC-3 cells showed a threefold lower uptake of tin in comparison to platinum (as cisplatin). Together with its higher activity this indicates a much higher cell inhibition potential of the tin compounds (calculated to ca. 50 to 100 times). Morphological analysis suggested that the compounds induce apoptosis in PC-3 cells, and flow cytometry analysis revealed that 1 and 2 induce autophagy as well as NO (nitric oxide) production. A2 - C1 - Bioorganic Chemistry ER - TY - JOUR ID - 570 TI - Direct Delivery of Health Promoting β-Asp-Arg Dipeptides via Stable Co-expression of Cyanophycin and the Cyanophycinase CphE241 in Tobacco Plants JO - Front. Plant Sci. PY - 2020 SP - 842 AU - Nausch, H. AU - Dorn, M. AU - Frolov, A. AU - Hoedtke, S. AU - Wolf, P. AU - Broer, I. AU - VL - 11 UR - DO - 10.3389/fpls.2020.00842 AB - Feed supplementation with β-arginine-aspartate dipeptides (β-Asp-Arg DP) shows growth promoting effects in feeding trials with fish and might also be beneficial for pig and poultry farming. Currently, these DPs are generated from purified cyanophycin (CGP), with the help of the CGP-degrading enzyme cyanophycinase (CGPase). As alternative to an in vitro production, the DPs might be directly produced in feed crops. We already demonstrated that CGP can be produced in plastids of tobacco and potato, yielding up to 9.4% of the dry weight (DW). We also transiently co-expressed CGPases in the cytosol without degrading CGP in intact cells, while degradation occurs in the homogenized plant tissue. However, transient co-expression is not feasible for field-grown CGP plants, which is necessary for bulk production. In the present study, we proved that stable co-expression of the CGPase CphE241 in CGP-producing tobacco is sufficient to degrade 2.0% CGP/DW nearly completely within 3 h after homogenization of the leaves. In intact senescing leaves, CGP is partially released to the cytosol and degraded into DPs which limits the overall accumulation of CGP but not the level of the stable DPs. Even after 48 h, 54 μmol β-Asp-Arg DP/g DW could be detected in the extract, which correspond to 1.5% DP/DW and represents 84% of the expected amount. Thus, we developed a system for the production of β-Asp-Arg DP in field-grown plants. A2 - C1 - Bioorganic Chemistry ER - TY - JOUR ID - 569 TI - Using a qPCR device to screen for modulators of ABC transporter activity: A step-by-step protocol JO - J. Pharmacol. Toxicol. Methods PY - 2020 SP - 106882 AU - Möhle, L. AU - Schwarzová, B. AU - Krohn, M. AU - Stefan, S. M. AU - Pahnke, J. AU - VL - 104 UR - DO - 10.1016/j.vascn.2020.106882 AB - IntroductionAdenosine triphosphate (ATP)-binding cassette (ABC) transporters are transmembrane proteins which actively transport a large variety of substrates across biological membranes. ABC transporter overexpression can be the underlying cause of multidrug resistance in oncology. Moreover, it has been revealed that increased ABCC1 transporter activity can ameliorate behavioural changes and Aβ pathology in a rodent model of Alzheimer's disease and it is currently tested in AD patients.MethodsFinding substances that modulate ABC transporter activity (inhibitors and activators) is of high relevance and thus, different methods have been developed to screen for potential modulators. For this purpose, we have developed a cell-based assay to measure the kinetics of ABCC1-mediated efflux of a fluorescent dye using a common qPCR device (Agilent AriaMx).ResultsWe validated the specificity of our method with vanadate and benzbromarone controls. Furthermore, we provide a step-by-step protocol including statistical analysis of the resulting data and suggestions how to modify the protocol specifically to screen for activators of ABCC1.DiscussionOur approach is biologically more relevant than cell-free assays. The continuous detection of kinetics allows for a more precise quantification compared with assays with single end-point measurements. A2 - C1 - Bioorganic Chemistry ER - TY - JOUR ID - 568 TI - Rewarding compounds identified from the medicinal plant Rhodiola rosea JO - J. Exp. Biol. PY - 2020 SP - jeb223982 AU - Michels, B. AU - Franke, K. AU - Weiglein, A. AU - Sultani, H. AU - Gerber, B. AU - Wessjohann, L. A. AU - VL - 223 UR - https://doi.org/10.1242/jeb.223982 DO - 10.1242/jeb.223982 AB - Preparations of Rhodiola rosea root are widely used in traditional medicine. They can increase life span in worms and flies, and have various effects related to nervous system function in different animal species and humans. However, which of the compounds in R. rosea is mediating any one of these effects has remained unknown in most cases. Here, an analysis of the volatile and non-volatile low-molecular-weight constituents of R. rosea root samples was accompanied by an investigation of their behavioral impact on Drosophila melanogaster larvae. Rhodiola rosea root samples have an attractive smell and taste to the larvae, and exert a rewarding effect. This rewarding effect was also observed for R. rosea root extracts, and did not require activity of dopamine neurons that mediate known rewards such as sugar. Based on the chemical profiles of R. rosea root extracts and resultant fractions, a bioactivity-correlation analysis (AcorA) was performed to identify candidate rewarding compounds. This suggested positive correlations for – among related compounds – ferulic acid eicosyl ester (FAE-20) and β-sitosterol glucoside. A validation using these as pure compounds confirmed that the correlations were causal. Their rewarding effects can be observed even at low micromolar concentrations and thus at remarkably lower doses than for any known taste reward in the larva. We discuss whether similar rewarding effects, should they be observed in humans, would indicate a habit-forming or addictive potential. A2 - C1 - Bioorganic Chemistry ER - TY - JOUR ID - 567 TI - SpCas9- and LbCas12a-Mediated DNA Editing Produce Different Gene Knockout Outcomes in Zebrafish Embryos JO - Genes PY - 2020 SP - 740 AU - Meshalkina, D. A. AU - Glushchenko, A. S. AU - Kysil, E. V. AU - Mizgirev, I. V. AU - Frolov, A. AU - VL - 11 UR - DO - 10.3390/genes11070740 AB - CRISPR/Cas (Clustered Regularly Interspaced Short Palindromic Repeats/CRISPR associated protein) genome editing is a powerful technology widely used in current genetic research. In the most simple and straightforward way it can be applied for a gene knockout resulting from repair errors, induced by dsDNA cleavage by Cas nuclease. For decades, zebrafish (Danio rerio) has been known as a convenient model object of developmental biology. Both commonly used nucleases SpCas9 (Streptococcus pyogenes Cas9) and LbCas12a (Lachnospiraceae bacterium Cas12a) are extensively used in this model. Among them, LbCas12a is featured with higher specificity and efficiency of homology-directed editing in human cells and mouse. But the editing outcomes for these two nucleases in zebrafish are still not compared quantitatively. Therefore, to reveal possible advantages of one nuclease in comparison to the other in the context of gene knockout generation, we compare here the outcomes of repair of the DNA breaks introduced by these two commonly used nucleases in zebrafish embryos. To address this question, we microinjected the ribonucleoprotein complexes of the both nucleases with the corresponding guide RNAs in zebrafish zygotes and sequenced the target gene regions after three days of development. We found that LbCas12a editing resulted in longer deletions and more rare inserts, in comparison to those generated by SpCas9, while the editing efficiencies (percentage of mutated copies of the target gene to all gene copies in the embryo) of both nucleases were the same. On the other hand, overlapping of protospacers resulted in similarities in repair outcome, although they were cut by two different nucleases. Thus, our results indicate that the repair outcome depends both on the nuclease mode of action and on protospacer sequence. A2 - C1 - Bioorganic Chemistry ER - TY - JOUR ID - 566 TI - Isonitriles: Versatile handles for the bioorthogonal functionalization of proteins JO - ACS Omega PY - 2020 SP - 25505-25510 AU - Méndez, Y. AU - Vasco, A. V. AU - Humpierre, A. R. AU - Westermann, B. AU - VL - 5 UR - DO - 10.1021/acsomega.0c03728 AB - The property of the isonitrile group to enable the simultaneous α-addition of a strong electrophile and a nucleophile has always attracted the attention of organic chemists. Its versatility is augmented when recognizing that its high structural compactness, the inertia to most of the naturally occurring functional groups, and relatively prolonged physiological and metabolical stability, convert it into the smallest bioorthogonal group. The discovery and optimization of the isonitrile-tetrazine [4+1] cycloaddition as an alternative tool for the development of ligation and decaging strategies and the recently reported reaction of isonitriles with chlorooximes bring new opportunities for the utilization of this functional group in biological systems. Although several approaches have been reported for the synthesis of isonitrile-modified carbohydrates and polysaccharides, its incorporation in proteins has been barely explored. Besides compiling the reported methods for the assembly of isonitrile-modified proteins, this Mini-Review aims at calling attention to the real potential of this modification for protein ligation, decaging, immobilization, imaging, and many other applications at a low structural and functional cost. A2 - C1 - Bioorganic Chemistry ER - TY - JOUR ID - 562 TI - Does Protein Glycation Impact on the Drought-Related Changes in Metabolism and Nutritional Properties of Mature Pea (Pisum sativum L.) Seeds? JO - Int. J. Mol. Sci. PY - 2020 SP - 567 AU - Leonova, T. AU - Popova, V. AU - Tsarev, A. AU - Henning, C. AU - Antonova, K. AU - Rogovskaya, N. AU - Vikhnina, M. AU - Baldensperger, T. AU - Soboleva, A. AU - Dinastia, E. AU - Dorn, M. AU - Shiroglasova, O. AU - Grishina, T. AU - Balcke, G. U. AU - Ihling, C. AU - Smolikova, G. AU - Medvedev, S. AU - Zhukov, V. A. AU - Babakov, V. AU - Tikhonovich, I. A. AU - Glomb, M. A. AU - Bilova, T. AU - Frolov, A. AU - VL - 21 UR - DO - 10.3390/ijms21020567 AB - Protein glycation is usually referred to as an array of non-enzymatic post-translational modifications formed by reducing sugars and carbonyl products of their degradation. The resulting advanced glycation end products (AGEs) represent a heterogeneous group of covalent adducts, known for their pro-inflammatory effects in mammals, and impacting on pathogenesis of metabolic diseases and ageing. In plants, AGEs are the markers of tissue ageing and response to environmental stressors, the most prominent of which is drought. Although water deficit enhances protein glycation in leaves, its effect on seed glycation profiles is still unknown. Moreover, the effect of drought on biological activities of seed protein in mammalian systems is still unstudied with respect to glycation. Therefore, here we address the effects of a short-term drought on the patterns of seed protein-bound AGEs and accompanying alterations in pro-inflammatory properties of seed protein in the context of seed metabolome dynamics. A short-term drought, simulated as polyethylene glycol-induced osmotic stress and applied at the stage of seed filling, resulted in the dramatic suppression of primary seed metabolism, although the secondary metabolome was minimally affected. This was accompanied with significant suppression of NF-kB activation in human SH-SY5Y neuroblastoma cells after a treatment with protein hydrolyzates, isolated from the mature seeds of drought-treated plants. This effect could not be attributed to formation of known AGEs. Most likely, the prospective anti-inflammatory effect of short-term drought is related to antioxidant effect of unknown secondary metabolite protein adducts, or down-regulation of unknown plant-specific AGEs due to suppression of energy metabolism during seed filling. A2 - C1 - Cell and Metabolic Biology; Bioorganic Chemistry ER - TY - JOUR ID - 557 TI - Cardenolide glycosides from Streptocaulon tomentosum WIGHT & ARNOTT(Asclepiadaceae) in MYANMAR JO - J. Myanmar Acad. Arts Sci. PY - 2020 SP - 1-11 AU - Khine, M. M. AU - Arnold, N. AU - Franke, K. AU - Wessjohann, L. A. AU - VL - XVIII No. 1A UR - AB - This  paper describes  the isolation and comparative studies on NMR spectra of cardenolide glycosides from Streptocaulon tomentosum Wight & Arnott (Asclepiadaceae).  Nine cardenolides were isolated from the roots of Streptocaulon tomentosum. by column chromatography and identified by NMR spectroscopy. They are 17α-H-periplogenin, 17α-H-periplogenin-β-D digitoxose,17α-H-periplogenin-β-D cymarose, 17α-H-periplogenin-β-glucosyl-(1-4)-2-O-acetyl-digitalose, 17β-H-periplogenin, 17β-H-periplogenin-β-D digitoxose, 17β-H-periplogenin-β-D cymarose, 17α -H-digitoxigenin, and 17 α-H-digitoxigenin-β-D-digitoxoside. Comparative studies on NMR spectra of cardenolide glycosides were carried out. Six cardenolides isolated from Streptocaulon tomentosum were tested for their antiproliferative activity in vitro against MCF-7 (human breast cancer cell line) and L 929 (mouse fibroblast cell line). Among these six cardenolides, 17α-H-periplogenin-3-O-β-D-digitoxoside and 17α-H-periplogenin-3-O-β-D-cymaroside exhibit significant antiproliferative activity (IC50 values, < 1μM) against MCF-7. Four cardenolides  were examined for their cellular viability in the tumor cell and  U 937  (human leukemic cell line) at concentrations 100 μM, 10 μM, and 1 μM. All these four cardenolides  show the induction of apoptosis at 100 μM and 10 μM in both cell lines. A2 - C1 - Bioorganic Chemistry ER - TY - JOUR ID - 556 TI - Cichorins D–F: Three New Compounds from Cichorium intybus and Their Biological Effects JO - Molecules PY - 2020 SP - 4160 AU - Khan, M. F. AU - Nasr, F. A. AU - Noman, O. M. AU - Alyhya, N. A. AU - Ali, I. AU - Saoud, M. AU - Rennert, R. AU - Dube, M. AU - Hussain, W. AU - Green, I. R. AU - Basudan, O. A. M. AU - Ullah, R. AU - Anazi, S. H. AU - Hussain, H. AU - VL - 25 UR - https://doi.org/10.3390/molecules25184160 DO - 10.3390/molecules25184160 AB - Cichorium intybus L., (chicory) is employed in various traditional medicines to treat a wide range of diseases and disorders. In the current investigation, two new naphthalane derivatives viz., cichorins D (1) and E (2), along with one new anthraquinone cichorin F (3), were isolated from Cichorium intybus. In addition, three previously reported compounds viz., β-sitosterol (4), β-sitosterol β-glucopyranoside (5), and stigmasterol (6) were also isolated from Cichorium intybus. Their structures were established via extensive spectroscopic data, including 1D (1H and 13C) and 2D NMR (COSY, HSQC and HMBC), and ESIMS. Cichorin E (2) has a weak cytotoxic effect on breast cancer cells (MDA-MB-468: IC50: 85.9 µM) and Ewing’s sarcoma cells (SK-N-MC: IC50: 71.1 µM); cichorin F (3) also illustrated weak cytotoxic effects on breast cancer cells (MDA-MB-468: IC50: 41.0 µM and MDA-MB-231: IC50: 45.6 µM), and SK-N-MC cells (IC50: 71.9 µM). Moreover compounds 1–3 did not show any promising anthelmintic effects. A2 - C1 - Bioorganic Chemistry ER - TY - JOUR ID - 549 TI - Evaluation of plant sources for antiinfective lead compound discovery by correlating phylogenetic, spatial, and bioactivity data JO - Proc. Natl. Acad. Sci. U.S.A. PY - 2020 SP - 12444-12451 AU - Holzmeyer, L. AU - Hartig, A.-K. AU - Franke, K. AU - Brandt, W. AU - Muellner-Riehl, A. N. AU - Wessjohann, L. A. AU - Schnitzler, J. AU - VL - 117 UR - DO - 10.1073/pnas.1915277117 AB - The continued high rates of using antibiotics in healthcare and livestock, without sufficient new compounds reaching the market, has led to a dramatic increase in antimicrobial resistance, with multidrug-resistant bacteria emerging as a major public health threat worldwide. Because the vast majority of antiinfectives are natural products or have originated from them, we assessed the predictive power of plant molecular phylogenies and species distribution modeling in the search for clades and areas which promise to provide a higher probability of delivering new antiinfective compound leads. Our approach enables taxonomically and spatially targeted bioprospecting and supports the battle against the global antimicrobial crisis. A2 - C1 - Bioorganic Chemistry ER - TY - JOUR ID - 545 TI - High-Throughput Fingerprinting of Rhizobial Free Fatty Acids by Chemical Thin-Film Deposition and Matrix-Assisted Laser Desorption/Ionization Mass Spectrometry JO - Methods Protoc. PY - 2020 SP - 36 AU - Gladchuk, A. AU - Shumilina, J. AU - Kusnetsova, A. AU - Bureiko, K. AU - Billig, S. AU - Tsarev, A. AU - Alexandrova, I. AU - Leonova, L. AU - Zhukov, V. A. AU - Tikhonovich, I. A. AU - Birkemeyer, C. AU - Podolskaya, E. AU - Frolov, A. AU - VL - 3 UR - DO - 10.3390/mps3020036 AB - Fatty acids (FAs) represent an important class of metabolites, impacting on membrane building blocks and signaling compounds in cellular regulatory networks. In nature, prokaryotes are characterized with the most impressing FA structural diversity and the highest relative content of free fatty acids (FFAs). In this context, nitrogen-fixing bacteria (order Rhizobiales), the symbionts of legumes, are particularly interesting. Indeed, the FA profiles influence the structure of rhizobial nodulation factors, required for successful infection of plant root. Although FA patterns can be assessed by gas chromatography—(GC-) and liquid chromatography—mass spectrometry (LC-MS), sample preparation for these methods is time-consuming and quantification suffers from compromised sensitivity, low stability of derivatives and artifacts. In contrast, matrix-assisted laser desorption/ionization-time of flight mass spectrometry (MALDI-TOF-MS) represents an excellent platform for high-efficient metabolite fingerprinting, also applicable to FFAs. Therefore, here we propose a simple and straightforward protocol for high-throughput relative quantification of FFAs in rhizobia by combination of Langmuir technology and MALDI-TOF-MS featuring a high sensitivity, accuracy and precision of quantification. We describe a step-by-step procedure comprising rhizobia culturing, pre-cleaning, extraction, sample preparation, mass spectrometric analysis, data processing and post-processing. As a case study, a comparison of the FFA metabolomes of two rhizobia species—Rhizobium leguminosarum and Sinorhizobium meliloti, demonstrates the analytical potential of the protocol. A2 - C1 - Bioorganic Chemistry ER - TY - JOUR ID - 537 TI - Characterization of antibacterial proanthocyanidins of Dalbergia monetaria, an amazonian medicinal plant, by UHPLC-HRMS/MS JO - Planta Med. PY - 2020 SP - 858– 866 AU - de Moura, P. H. B. AU - de Sousa, A. A. AU - Porzel, A. AU - Wessjohann, L. A. AU - Leal, I. C. R. AU - Martins, R. C. C. AU - VL - 86 UR - https://doi.org/10.1055/a-1170-8016 DO - 10.1055/a-1170-8016 AB - Dalbergia monetaria is an Amazonian plant whose bark is widely used to treat urinary tract infections. This paper describes a bio-guided study of ethanolic extracts from the bark and leaves of D. monetaria, in a search for metabolites active against human pathogenic bacteria. In vitro assays were performed against 10 bacterial strains, highlighting methicillin-sensitive Staphylococcus aureus and methicillin-resistant Staphylococcus aureus and Pseudomonas aeruginosa. Fractioning of the extracts was performed using instrumental and classical techniques, and samples were characterized by UHPLC-HRMS/MS. Ethyl acetate fractions from bark and leaves showed similar antibacterial activities. EAFB is enriched in isoflavone C-glucosides and EAFL enriched in proanthocyanidins. Subfractions from EAFL presented higher activity and showed a complex profile of proanthocyanidins constructed by (epi)-cassiaflavan and (epi)-catechin units, including dimers, trimers and tetramers. The fragmentation pattern emphasized the neutral loss of cassiaflavan units by quinone-methide fission. Fraction SL7-6, constituted by (ent)-cassiaflavan-(ent)-cassiaflavan-(epi)-catechin isomers, showed the lowest MIC against the S. aureus and P. aeruginosa with values corresponding to 64 and 32 µg/mL, respectively. Cassiaflavan-proanthocyanidins have not been found previously in another botanical genus, except in Cassia, and the traditional medicinal use of D. monetaria might be related to the antibacterial activity of proanthocyanidins characterized in the species. A2 - C1 - Bioorganic Chemistry ER - TY - JOUR ID - 535 TI - Passiflora mucronata leaves extracts obtained from different methodologies: a phytochemical study based on cytotoxic and apoptosis activities of triterpenes and phytosterols constituents JO - Braz. J. Pharm. Sci. PY - 2020 SP - e17666 AU - da Silva, I. C. V. AU - Silva, I. C. V. d. AU - de Oliveira, P. F. AU - Oliveira, P. F. d. AU - Barbosa, G. M. AU - Wessjohann, L. A. AU - Cardozo-Filho, L. AU - Holandino, C. AU - Muzitano, M. F. AU - Leal, I. C. R. AU - VL - 56 UR - http://dx.doi.org/10.1590/s2175-97902019000417666 DO - 10.1590/s2175-97902019000417666 AB - Cancer is one of the most prevalent diseases worldwide and the natural products could be a source of bioactive compounds. Passiflora mucronata (PM) belongs to a very known vegetal genus, although, there are no studies about cytotoxic activity or isolated compounds. Different extracts from PM were obtained by liquid-liquid partition (P), Soxhlet (Sox) and supercritical fluid (SFE1-5) extraction techniques, being compared concerning their yields, chemical profile and cytotoxicity. The Sox extracts showed the highest yields (6.03%: hexane; 2.51%: dichloromethane) followed by SFE (from 4.34 to 1.63%) and partitions (1.06 and 2.26%). The hexane partition (HP) showed the best cytotoxic activity against K562 cell line (IC50 = 18.72 µg.mL-1). From HP, the following compounds were identified and analysed its cytotoxic activities: β-amyrin (IC50 = 3.92 µg.mL-1), β-sitosterol (IC50 = 3.37 µg.mL-1), stigmasterol (IC50 = 3.31 µg.mL-1) and oleanolic acid. Stigmasterol induced about 75% of K562 total apoptosis. The compounds were tested against MA-104 cell line and the selective index (SI) attributed (SI >10 for all compounds). This indicates good selectivity to K562 cell line at the expense of MA-104. This is the first time, identifying those compounds to PM . A2 - C1 - Bioorganic Chemistry ER - TY - JOUR ID - 533 TI - Chemical constituents of the roots of Ormocarpum sennoides subsp. zanzibaricum JO - Biochem. Syst. Ecol. PY - 2020 SP - 104142 AU - Chalo, D. M. AU - Kakudidi, E. AU - Origa-Oryem, H. AU - Namukobe, J. AU - Franke, K. AU - Yenesew, A. AU - Wessjohann, L. A. AU - VL - 93 UR - https://doi.org/10.1016/j.bse.2020.104142 DO - 10.1016/j.bse.2020.104142 AB - Phytochemical investigation of the roots of O. sennoides subsp. zanzibaricum Brenan & J.B. Gillett resulted in the isolation of three biflavonoids (trime-chamaejasmin, (+)- chamaejasmin, (+)-liquiritigeninyl-(I-3,II-3)-naringenin), one bi-4-phenyldihydrocoumarin (diphysin), one isoflavan (glabridin), one triterpenoid (3-O-acetyloleanoic acid) and a phytosterol (β-sitosterol). Compounds were identified by detailed MS, 1D and 2D NMR spectroscopic analyses. Their absolute configurations were elucidated based on ECD spectra. The previously undescribed trime-chamaejasmin represents a bis-epi-chamaejasmenin C diastereomer. The chemophenetic significance is discussed in detail. The results contribute to the phytochemical characterization of the genus Ormocarpum and suggest a close chemophenetic relationship with other genera within the subfamily Papilionoideae. Furthermore, this report provides baseline data for comparing the two infraspecific taxa of O. sennoides (Willd.) DC. A2 - C1 - Bioorganic Chemistry ER - TY - JOUR ID - 529 TI - Fingolimod as a Treatment in Neurologic Disorders Beyond Multiple Sclerosis JO - Drugs R. D. PY - 2020 SP - 197-207 AU - Bascuñana, P. AU - Möhle, L. AU - Brackhan, M. AU - Pahnke, J. AU - VL - 20 UR - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7419396/ DO - 10.1007/s40268-020-00316-1 AB - Fingolimod is an approved treatment for relapsing–remitting multiple sclerosis (MS), and its properties in different pathways have raised interest in therapy research for other neurodegenerative diseases. Fingolimod is an agonist of sphingosine-1-phosphate (S1P) receptors. Its main pharmacologic effect is immunomodulation by lymphocyte homing, thereby reducing the numbers of T and B cells in circulation. Because of the ubiquitous expression of S1P receptors, other effects have also been described. Here, we review preclinical experiments evaluating the effects of treatment with fingolimod in neurodegenerative diseases other than MS, such as Alzheimer’s disease or epilepsy. Fingolimod has shown neuroprotective effects in different animal models of neurodegenerative diseases, summarized here, correlating with increased brain-derived neurotrophic factor and improved disease phenotype (cognition and/or motor abilities). As expected, treatment also induced reductions in different neuroinflammatory markers because of not only inhibition of lymphocytes but also direct effects on astrocytes and microglia. Furthermore, fingolimod treatment exhibited additional effects for specific neurodegenerative disorders, such as reduction of amyloid-β production, and antiepileptogenic properties. The neuroprotective effects exerted by fingolimod in these preclinical studies are reviewed and support the translation of fingolimod into clinical trials as treatment in neurodegenerative diseases beyond neuroinflammatory conditions (MS). A2 - C1 - Bioorganic Chemistry ER - TY - CHAP ID - 191 TI - Colombia hacia una sociedad del conocimiento. Reflexiones y propuestas T2 - PB - PY - 2020 SP - 1-450 AU - Restrepo, S. AU - Samper, C. AU - di Palma, F. AU - Hodson, E. AU - Torres, M. AU - Reol, E. M. AU - Eddi, M. AU - Wessjohann, L. AU - Jaramillo, G. P. AU - et al., . AU - VL - UR - https://minciencias.gov.co/sites/default/files/upload/paginas/ebook-_colombia_hacia_una_sociedad_del_conocimiento.pdf SN - 978-958-5135-12-3 AB - A2 - C1 - Bioorganic Chemistry ER - TY - CHAP ID - 15 TI - Insights into the Phytochemistry of the Cuban Endemic Medicinal Plant Phyllanthus orbicularis: Fideloside, a Novel Bioactive 8-C-glycosyl 2,3-Dihydroflavonol T2 - Natural Products and Drug Discovery PB - Molecules PY - 2020 SP - 79-92 AU - Francioso, A. AU - Franke, K. AU - Villani, C. AU - Mosca, L. AU - d’Erme, M. AU - Frischbutter, S. AU - Brandt, W. AU - Sanchez-Lamar, A. AU - Wessjohann, L. AU - VL - UR - https://doi/103390./books978-3-03928-747-5 SN - 978-3-03928-746-8 DO - 10.3390/books978-3-03928-747-5 AB - Phyllanthus orbicularis (Phyllanthaceae) is an endemic evergreen tropical plant of Cuba that grows in the western part of the island and is used in traditional medicine as an infusion. The aqueous extract of this plant presents a wide range of pharmacological activitiessuch as antimutagenic, antioxidant and antiviral effects. Given the many beneficial effects and the great interest in the development of new pharmacological products from natural sources, the aim of this work was to investigate the phytochemistry of this species and to elucidate the structure of the main bioactive principles. Besides thepresence of several known polyphenols, the major constituent was hitherto not described. The chemical structure of this compound, here named Fideloside, was elucidated by means of HR-ESIMS/MSn, 1D/2D NMR, FT-IR, and ECD as (2R,3R)-(−)-3’,4 ,5,7-tetrahydroxydihydroflavonol-8-C- -D-glucopyranoside. The compound, as well as the plant aqueous preparations, showed promising bioactive properties, i.e., anti-inflammatory capacity in human explanted monocytes, corroborating future pharmacological use for this new natural C-glycosyl flavanonol. A2 - Pinarosa Avato C1 - Bioorganic Chemistry ER - TY - JOUR ID - 748 TI - Influence of Multidrug Resistance-Associated Proteins on the Excretion of the ABCC1 Imaging Probe 6-Bromo-7-[11C]Methylpurine in Mice JO - Mol. Imaging Biol. PY - 2019 SP - 306-316 AU - Zoufal, V. AU - Mairinger, S. AU - Krohn, M. AU - Wanek, T. AU - Filip, T. AU - Sauberer, M. AU - Stanek, J. AU - Traxl, A. AU - Schuetz, J. D. AU - Kuntner, C. AU - Pahnke, J. AU - Langer, O. AU - VL - 21 UR - DO - 10.1007/s11307-018-1230-y AB - PurposeMultidrug resistance-associated proteins (MRPs) mediate the hepatobiliary and renal excretion of many drugs and drug conjugates. The positron emission tomography (PET) tracer 6-bromo-7-[11C]methylpurine is rapidly converted in tissues by glutathione-S-transferases into its glutathione conjugate, and has been used to measure the activity of Abcc1 in the brain and the lungs of mice. Aim of this work was to investigate if the activity of MRPs in excretory organs can be measured with 6-bromo-7-[11C]methylpurine.ProceduresWe performed PET scans with 6-bromo-7-[11C]methylpurine in groups of wild-type, Abcc4(−/−) and Abcc1(−/−) mice, with and without pre-treatment with the prototypical MRP inhibitor MK571.Results6-Bromo-7-[11C]methylpurine-derived radioactivity predominantly underwent renal excretion. In blood, MK571 treatment led to a significant increase in the AUC and a decrease in the elimination rate constant of radioactivity (kelimination,blood). In the kidneys, there were significant decreases in the rate constant for radioactivity uptake from the blood (kuptake,kidney), kelimination,kidney, and the rate constant for tubular secretion of radioactivity (kurine). Experiments in Abcc4(−/−) mice indicated that Abcc4 contributed to renal excretion of 6-bromo-7-[11C]methylpurine-derived radioactivity.ConclusionsOur data suggest that 6-bromo-7-[11C]methylpurine may be useful to assess the activity of MRPs in the kidneys as well as in other organs (brain, lungs), although further work is needed to identify the MRP subtypes involved in the disposition of 6-bromo-7-[11C]methylpurine-derived radioactivity. A2 - C1 - Bioorganic Chemistry ER - TY - JOUR ID - 733 TI - Multiple Glycation Sites in Blood Plasma Proteins as an Integrated Biomarker of Type 2 Diabetes Mellitus JO - Int. J. Mol. Sci. PY - 2019 SP - 2329 AU - Soboleva, A. AU - Mavropulo-Stolyarenko, G. AU - Karonova, T. AU - Thieme, D. AU - Hoehenwarter, W. AU - Ihling, C. AU - Stefanov, V. AU - Grishina, T. AU - Frolov, A. AU - VL - 20 UR - DO - 10.3390/ijms20092329 AB - Type 2 diabetes mellitus (T2DM) is one of the most widely spread metabolic diseases. Because of its asymptomatic onset and slow development, early diagnosis and adequate glycaemic control are the prerequisites for successful T2DM therapy. In this context, individual amino acid residues might be sensitive indicators of alterations in blood glycation levels. Moreover, due to a large variation in the half-life times of plasma proteins, a generalized biomarker, based on multiple glycation sites, might provide comprehensive control of the glycemic status across any desired time span. Therefore, here, we address the patterns of glycation sites in highly-abundant blood plasma proteins of T2DM patients and corresponding age- and gender-matched controls by comprehensive liquid chromatography-mass spectrometry (LC-MS). The analysis revealed 42 lysyl residues, significantly upregulated under hyperglycemic conditions. Thereby, for 32 glycation sites, biomarker behavior was demonstrated here for the first time. The differentially glycated lysines represented nine plasma proteins with half-lives from 2 to 21 days, giving access to an integrated biomarker based on multiple protein-specific Amadori peptides. The validation of this biomarker relied on linear discriminant analysis (LDA) with random sub-sampling of the training set and leave-one-out cross-validation (LOOCV), which resulted in an accuracy, specificity, and sensitivity of 92%, 100%, and 85%, respectively. A2 - C1 - Bioorganic Chemistry ER - TY - JOUR ID - 732 TI - Glycation of Plant Proteins: Regulatory Roles and Interplay with Sugar Signalling? JO - Int. J. Mol. Sci. PY - 2019 SP - 2366 AU - Shumilina, J. AU - Kusnetsova, A. AU - Tsarev, A. AU - Janse van Rensburg, H. C. AU - Medvedev, S. AU - Demidchik, V. AU - Van den Ende, W. AU - Frolov, A. AU - VL - 20 UR - DO - 10.3390/ijms20092366 AB - Glycation can be defined as an array of non-enzymatic post-translational modifications of proteins formed by their interaction with reducing carbohydrates and carbonyl products of their degradation. Initial steps of this process rely on reducing sugars and result in the formation of early glycation products—Amadori and Heyns compounds via Schiff base intermediates, whereas their oxidative degradation or reactions of proteins with α-dicarbonyl compounds yield a heterogeneous group of advanced glycation end products (AGEs). These compounds accompany thermal processing of protein-containing foods and are known to impact on ageing, pathogenesis of diabetes mellitus and Alzheimer’s disease in mammals. Surprisingly, despite high tissue carbohydrate contents, glycation of plant proteins was addressed only recently and its physiological role in plants is still not understood. Therefore, here we summarize and critically discuss the first steps done in the field of plant protein glycation during the last decade. We consider the main features of plant glycated proteome and discuss them in the context of characteristic metabolic background. Further, we address the possible role of protein glycation in plants and consider its probable contribution to protein degradation, methylglyoxal and sugar signalling, as well as interplay with antioxidant defense. A2 - C1 - Bioorganic Chemistry ER - TY - JOUR ID - 729 TI - Synthesis and biochemical studies of novel organic selenides with increased selectivity for hepatocellular carcinoma and breast adenocarcinoma JO - Eur. J. Med. Chem. PY - 2019 SP - 515-526 AU - Shaaban, S. AU - Ashmawy, A. M. AU - Negm, A. AU - Wessjohann, L. A. AU - VL - 179 UR - DO - 10.1016/j.ejmech.2019.06.075 AB - Nineteen organoselenides were synthesized and tested for their intrinsic cytotoxicity in hepatocellular carcinoma (HepG2) and breast adenocarcinoma (MCF-7) cell lines and their corresponding selective cytotoxicity (SI) was estimated using normal lung fibroblast (WI-38) cells. Most of the organic selenides exhibited good anticancer activity, and this was more pronounced in HepG2 cells. Interestingly, the naphthoquinone- (5), thiazol- (12), and the azo-based (13) organic selenides demonstrated promising SI (up to 76). Furthermore, the amine 4c, naphthoquinone 5, and azo-based 13 and 15 organic selenides were able to down-regulate the expression of Bcl-2 and up-regulate the expression levels of IL-2, IL-6 and CD40 in HepG2 cells compared to untreated cells. Moreover, most of the synthesized candidates manifested good free radical-scavenging and GPx-like activities comparable to vitamin C and ebselen. The obtained results suggested that some of the presented organoselenium candidates have promising anti-HepG2 and antioxidant activities. A2 - C1 - Bioorganic Chemistry ER - TY - JOUR ID - 727 TI - Chlorambucil Conjugated Ugi Dendrimers with PAMAM-NH2 Core and Evaluation of Their Anticancer Activity JO - Pharmaceutics PY - 2019 SP - 59 AU - Seixas, N. AU - Ravanello, B. B. AU - Morgan, I. AU - Kaluđerović, G. N. AU - Wessjohann, L. A. AU - VL - 11 UR - DO - 10.3390/pharmaceutics11020059 AB - Herein, a new Ugi multicomponent reaction strategy is described to enhance activity and solubility of the chemotherapeutic drug chlorambucil through its conjugation to poly(amidoamine) (PAMAM-NH2) dendrimers with the simultaneous introduction of lipidic (i-Pr) and cationic (–NH2) or anionic (–COOH) groups. Standard viability assays were used to evaluate the anticancer potential of the water-soluble dendrimers against PC-3 prostate and HT-29 colon cancer cell lines, as well as non-cancerous mouse NIH3T3 fibroblasts. It could be demonstrated that the anticancer activity against PC-3 cells was considerably improved when both chlorambucil and –NH2 (cationic) groups were present on the dendrimer surface (1b). Additionally, this dendrimer showed activity only against the prostate cancer cells (PC-3), while it did not affect colon cancer cells and fibroblasts significantly. The cationic chlorambucil-dendrimer 1b blocks PC-3 cells in the G2/M phase and induces caspase independent apoptosis. A2 - C1 - Bioorganic Chemistry ER - TY - JOUR ID - 705 TI - Thin Film Chemical Deposition Techniques as a Tool for Fingerprinting of Free Fatty Acids by Matrix-Assisted Laser Desorption/Ionization Time-of-Flight Mass Spectrometry JO - Anal. Chem. PY - 2019 SP - 1636-1643 AU - Podolskaya, E. P. AU - Gladchuk, A. S. AU - Keltsieva, O. A. AU - Dubakova, P. S. AU - Silyavka, E. S. AU - Lukasheva, E. AU - Zhukov, V. AU - Lapina, N. AU - Makhmadalieva, M. R. AU - Gzgzyan, A. M. AU - Sukhodolov, N. G. AU - Krasnov, K. A. AU - Selyutin, A. A. AU - Frolov, A. AU - VL - 91 UR - DO - 10.1021/acs.analchem.8b05296 AB - Metabolic fingerprinting is a powerful analytical technique, giving access to high-throughput identification and relative quantification of multiple metabolites. Because of short analysis times, matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS) is the preferred instrumental platform for fingerprinting, although its power in analysis of free fatty acids (FFAs) is limited. However, these metabolites are the biomarkers of human pathologies and indicators of food quality. Hence, a high-throughput method for their fingerprinting is required. Therefore, here we propose a MALDI-TOF-MS method for identification and relative quantification of FFAs in biological samples of different origins. Our approach relies on formation of monomolecular Langmuir films (LFs) at the interphase of aqueous barium acetate solution, supplemented with low amounts of 2,5-dihydroxybenzoic acid, and hexane extracts of biological samples. This resulted in detection limits of 10–13–10–14 mol and overall method linear dynamic range of at least 4 orders of magnitude with accuracy and precision within 2 and 17%, respectively. The method precision was verified with eight sample series of different taxonomies, which indicates a universal applicability of our approach. Thereby, 31 and 22 FFA signals were annotated by exact mass and identified by tandem MS, respectively. Among 20 FFAs identified in Fucus algae, 14 could be confirmed by gas chromatography-mass spectrometry. A2 - C1 - Bioorganic Chemistry ER - TY - JOUR ID - 655 TI - Variation in Ceratonia siliqua pod metabolome in context of its different geographical origin, ripening stage and roasting process JO - Food Chem. PY - 2019 SP - 675-687 AU - Farag, M. A. AU - El-Kersh, D. M. AU - Ehrlich, A. AU - Choucry, M. A. AU - El-Seedi, H. AU - Frolov, A. AU - Wessjohann, L. A. AU - VL - 283 UR - DO - 10.1016/j.foodchem.2018.12.118 AB - Carob is a legume tree of a considerable commercial importance for the flavor and sweet industry. In this context, it is cultivated mostly for its pods, which are known for their nutritive value and multiple health benefits. However, metabolite patterns, underlying these properties are still mostly uncharacterized. In this study, the role of geographical origin, ontogenetic changes and thermal processing on the Ceratonia siliqua pod metabolome was assessed by mass spectrometry (MS)-based metabolomics. Thereby, a total of 70 fruits primary metabolites, represented mainly by carbohydrates, organic and amino acids were detected. Analysis of secondary bioactive metabolites assessed by ultra-high-performance liquid chromatography-electrospray ionization high resolution mass spectrometry (UHPLC-ESI-HR-MS) revealed in total 83 signals. The major signals, most significantly contributing in discrimination of C. siliqua specimens were assigned to tannins and flavonoids. PCA models derived from either UHPLC-MS or GC-MS proved to be powerful tools for discrimination of C. siliqua specimens. A2 - C1 - Bioorganic Chemistry ER - TY - JOUR ID - 644 TI - The synthetic tubulysin derivative, tubugi-1, improves the innate immune response by macrophage polarization in addition to its direct cytotoxic effects in a murine melanoma model JO - Exp. Cell Res. PY - 2019 SP - 159-170 AU - Drača, D. AU - Mijatović, S. AU - Krajnović, T. AU - Pristov, J. B. AU - Đukić, T. AU - Kaluđerović, G. N. AU - Wessjohann, L. A. AU - Maksimović-Ivanić, D. AU - VL - 380 UR - DO - 10.1016/j.yexcr.2019.04.028 AB - Synthetic tubugis are equally potent but more stable than their natural forms. Their anticancer potential was estimated on a solid melanoma in vitro and in vivo. Tubugi-1 induced the apoptosis in B16 cells accompanied with strong intracellular production of reactive species, subsequently imposing glutathione and thiol group depletion. Paradoxically, membrane lipids were excluded from the cascade of intracellular oxidation, according to malondialdehyde decrease. Although morphologically apoptosis was typical, externalization of phosphatidylserine (PS) as an early apoptotic event was not detected. Even their exposition is pivotal for apoptotic cell eradication, primary macrophages successfully eliminated PS-deficient tubugi-1 induced apoptotic cells. The tumor volume in animals exposed to the drug in therapeutic mode was reduced in comparison to control as well as to paclitaxel-treated animals. Importantly, macrophages isolated from tubugi-1 treated animals possessed conserved phagocytic activity and were functionally and phenotypically recognized as M1. The cytotoxic effect of tubugi-1 is accomplished through its ability to polarize the macrophages toward M1, probably by PS independent apoptotic cell engulfment. The unique potential of tubugi-1 to prime the innate immune response through the induction of a specific pattern of tumor cell apoptosis can be of extraordinary importance from fundamental and applicable aspects. A2 - C1 - Bioorganic Chemistry ER - TY - JOUR ID - 643 TI - Synthetic Tubulysin Derivative, Tubugi-1, Against Invasive Melanoma Cells: The Cell Death Triangle JO - Anticancer Res. PY - 2019 SP - 5403-5415 AU - Drača, D. AU - Mijatović, S. AU - Krajnović, T. AU - Kaluđerović, G. N. AU - Wessjohann, L. A. AU - Maksimović-Ivanić, D. AU - VL - 39 UR - DO - 10.21873/anticanres.13734 AB - Background/Aim: Tubugi-1 is a more stable and accessible synthetic counterpart of natural tubulysins. This study aimed to evaluate its cytotoxic potential against anaplastic human melanoma cells. Materials and Methods: The viability of A-375 cells was determined by 3-(4,5-dimethythiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) and crystal violet assay. The type of cell death and proliferative rate were investigated using flow cytometry and fluorescent microscopy, while the molecular background was evaluated by western blot. Results: Tubugi-1 reduced the viability of A-375 cells, inducing massive micronucleation, followed by augmented expression of inhibitor of nuclear factor-κB and caspase-2, typical of a mitotic catastrophe. Disturbed proliferation and G2M block with prominent caspase activity, weakened the expression of B-cell lymphoma 2 and B-cell lymphoma 2-associated X transient up-regulation, coexisted with intensive autophagy. Specific inhibition of autophagy by chloroquine resulted in conversion from mitotic catastrophe to rapid apoptosis. Conclusion: Multilevel anticancer action of tubugi-1 is extended by co-application of an autophagy inhibitor, giving a new dimension in further preclinical advancement of this potential agent. A2 - C1 - Bioorganic Chemistry ER - TY - JOUR ID - 632 TI - 3D-clinorotation induces specific alterations in metabolite profiles of germinating Brassica napus L. seeds JO - Biol. Commun. PY - 2019 SP - 55-74 AU - Chantseva, V. AU - Bilova, T. AU - Smolikova, G. AU - Frolov, A. AU - Medvedev, S. AU - VL - 64 UR - DO - 10.21638/spbu03.2019.107 AB - During the whole history of their life on Earth, higher plants evolved under the constant gravity stimulus. Therefore, plants developed efficient mechanisms of gravity perception, underlying their ability to adjust the direction of growth to the gravity vector, i.e. the phenomenon of gravitropism. In this context, alterations in the magnitude and vector of the gravity field might compromise plant growth and development. This aspect was successfully addressed in gravity fields of low intensity (microgravity). On the other hand, microgravity can be simulated on the Earth by clinorotation, i.e. rotation of the experimental plant along one or several axes. This approach is routinely used for studies of gravity-related responses of crop plants, although the effect of simulated microgravity on the most sensitive ontogenetic stages — germination and seedling development — is still not sufficiently characterized. Recently, we addressed the effects of clinorotation on the proteome of germinating oilseed rape (Brassica napus) seeds. Here we extend this study to the seedling primary metabolome and address its changes in the presence of 3D-clinorotation. GC-MS analysis revealed essential alterations in patterns of sugars and sugar phosphates (specifically glucose-6-phosphate), methionine and glycerol. Thereby, abundances of individual metabolites showed high dispersion, indicating high lability and plasticity of the seedling metabolome. A2 - C1 - Bioorganic Chemistry ER - TY - JOUR ID - 631 TI - Age-related ultrastructural changes of the basement membrane in the mouse blood-brain barrier JO - J. Cell. Mol. Med. PY - 2019 SP - 819-827 AU - Ceafalan, L. C. AU - Fertig, T. E. AU - Gheorghe, T. C. AU - Hinescu, M. E. AU - Popescu, B. O. AU - Pahnke, J. AU - Gherghiceanu, M. AU - VL - 23 UR - DO - 10.1111/jcmm.13980 AB - The blood‐brain barrier (BBB) is essential for a functional neurovascular unit. Most studies focused on the cells forming the BBB, but very few studied the basement membrane (BM) of brain capillaries in ageing. We used transmission electron microscopy and electron tomography to investigate the BM of the BBB in ageing C57BL/6J mice. The thickness of the BM of the BBB from 24‐month‐old mice was double as compared with that of 6‐month‐old mice (107 nm vs 56 nm). The aged BBB showed lipid droplets gathering within the BM which further increased its thickness (up to 572 nm) and altered its structure. The lipids appeared to accumulate toward the glial side of the BM. Electron tomography showed that the lipid‐rich BM regions are located in small pockets formed by the end‐feet of astrocytes. These findings suggest an imbalance of the lipid metabolism and that may precede the structural alteration of the BM. These alterations may favour the accretion of abnormal proteins that lead to neurodegeneration in ageing. These findings warrant further investigation of the BM of brain capillaries and of adjoining cells as potential targets for future therapies. A2 - C1 - Bioorganic Chemistry ER - TY - JOUR ID - 623 TI - CYP76 Oxidation Network of Abietane Diterpenes in Lamiaceae Reconstituted in Yeast JO - J. Agr. Food Chem. PY - 2019 SP - 13437-13450 AU - Bathe, U. AU - Frolov, A. AU - Porzel, A. AU - Tissier, A. AU - VL - 67 UR - DO - 10.1021/acs.jafc.9b00714 AB - Rosemary and sage species from Lamiaceae contain high amounts of structurally related but diverse abietane diterpenes. A number of substances from this compound family have potential pharmacological activities and are used in the food and cosmetic industry. This has raised interest in their biosynthesis. Investigations in Rosmarinus officinalis and some sage species have uncovered two main groups of cytochrome P450 oxygenases that are involved in the oxidation of the precursor abietatriene. CYP76AHs produce ferruginol and 11-hydroxyferruginol, while CYP76AKs catalyze oxidations at the C20 position. Using a modular Golden-Gate-compatible assembly system for yeast expression, these enzymes were systematically tested either alone or in combination. A total of 14 abietane diterpenes could be detected, 8 of which have not been reported thus far. We demonstrate here that yeast is a valid system for engineering and reconstituting the abietane diterpene network, allowing for the discovery of novel compounds with potential bioactivity. A2 - C1 - Bioorganic Chemistry; Cell and Metabolic Biology ER - TY - JOUR ID - 622 TI - Analysis of Chemically Labile Glycation Adducts in Seed Proteins: Case Study of Methylglyoxal-Derived Hydroimidazolone 1 (MG-H1) JO - Int. J. Mol. Sci. PY - 2019 SP - 3659 AU - Antonova, K. AU - Vikhnina, M. AU - Soboleva, A. AU - Mehmood, T. AU - Heymich, M.-L. AU - Leonova, T. AU - Bankin, M. AU - Lukasheva, E. AU - Gensberger-Reigl, S. AU - Medvedev, S. AU - Smolikova, G. AU - Pischetsrieder, M. AU - Frolov, A. AU - VL - 20 UR - DO - 10.3390/ijms20153659 AB - Seeds represent the major source of food protein, impacting on both human nutrition and animal feeding. Therefore, seed quality needs to be appropriately addressed in the context of viability and food safety. Indeed, long-term and inappropriate storage of seeds might result in enhancement of protein glycation, which might affect their quality and longevity. Glycation of seed proteins can be probed by exhaustive acid hydrolysis and quantification of the glycation adduct Nɛ-(carboxymethyl)lysine (CML) by liquid chromatography-mass spectrometry (LC-MS). This approach, however, does not allow analysis of thermally and chemically labile glycation adducts, like glyoxal-, methylglyoxal- and 3-deoxyglucosone-derived hydroimidazolones. Although enzymatic hydrolysis might be a good solution in this context, it requires aqueous conditions, which cannot ensure reconstitution of seed protein isolates. Because of this, the complete profiles of seed advanced glycation end products (AGEs) are not characterized so far. Therefore, here we propose the approach, giving access to quantitative solubilization of seed proteins in presence of sodium dodecyl sulfate (SDS) and their quantitative enzymatic hydrolysis prior to removal of SDS by reversed phase solid phase extraction (RP-SPE). Using methylglyoxal-derived hydroimidazolone 1 (MG-H1) as a case example, we demonstrate the applicability of this method for reliable and sensitive LC-MS-based quantification of chemically labile AGEs and its compatibility with bioassays. A2 - C1 - Bioorganic Chemistry ER - TY - JOUR ID - 700 TI - In vitro anticancer evaluation of novel triphenyltin(IV) compounds with some N-acetyl-S-(naphthoquinone)cysteine derivatives JO - J. Serb. Chem. Soc. PY - 2019 SP - 1119-1127 AU - Pantelić, N. ?. AU - Lerbs, M. AU - Wolf, K. AU - Wessjohann, L. A. AU - Kaluđerović, G. N. AU - VL - 84 UR - DO - 10.2298/JSC190322032P AB - Triphenyltin(IV) compounds with naphthoquinone derivatives containing N-acetylcysteine, N-acetyl-S-(1,2-dion-4-naphthyl)cysteine (1,2-NQC), 1, and N-acetyl-S-(1,4-dion-2-naphthyl)cysteine (1,4-NQC), 2, were synthesized and characterized by elemental microanalysis, IR, multinuclear (1H, 13C, 119Sn) NMR spectroscopy as well as HR-ESI mass spectrometry. With the aim of in vitro anticancer activity determination of ligand precursors and novel synthesized organotin(IV) compounds against human cervix adenocarcinoma (HeLa), human colon carcinoma (HT-29), and melanoma carcinoma cell line (B16F10), MTT colorimetric assay method was applied. The results indicate that synthesized compounds exhibited remarkable antiproliferative activity toward all tested cell lines with IC50 in the range of 0.17 to 0.87 μM. Complex 1 showed the greatest activity against HT-29 cells, with IC50 value of 0.21 ± 0.01 μM, 119 times better than cisplatin, while complex 2 demonstrated the highest activity toward HeLa cells, IC50 = 0.17 ± 0.01 μM, which is ~26 times better than cisplatin. A2 - C1 - Bioorganic Chemistry ER - TY - JOUR ID - 699 TI - French maritime pine bark treatment decelerates plaque development and improves spatial memory in Alzheimer's disease mice JO - Phytomedicine PY - 2019 SP - 39-48 AU - Paarmann, K. AU - Prakash, S. R. AU - Krohn, M. AU - Möhle, L. AU - Brackhan, M. AU - Brüning, T. AU - Eiriz, I. AU - Pahnke, J. AU - VL - 57 UR - DO - 10.1016/j.phymed.2018.11.033 AB - BackgroundPlant extracts are increasingly investigated as potential drugs against Alzheimer's disease (AD) and dementia in general. Pycnogenol is an extract from the bark of the French maritime pine (Pinus pinaster Aiton subsp. atlantica) with known anti-oxidative and neuroprotective effects.Hypothesis/PurposePycnogenol is thought to improve cognitive functions in elderly. We wanted to investigate and quantify these effects in a model system of cerebral ß-amyloidosis/AD.Study design/methodsThis study experimentally assessed the effects of Pycnogenol on AD-related pathology in a ß-amyloidosis mouse model. APP-transgenic mice and controls were treated orally in a pre-onset and post-onset treatment paradigm. The effects of Pycnogenol were characterized by analysing ß-amyloid (Aß) plaques, number of neurons, glia coverage, myelination pattern, and cortical coverage with axons using immunohistochemistry. Aß levels were quantified using ELISA and gene expression levels of APP-processing enzymes ADAM10, BACE1 and IDE protein levels were determined by Western blot. Behavioural changes in circadian rhythm were monitored and spatial memory / cognition was assessed using a water maze test.ResultsPycnogenol significantly decreased the number of plaques in both treatment paradigms but did not alter levels of soluble Aß or the gene expression of APP-processing enzymes. The morphological analyses revealed no changes in the number of neurons, astrocytes, microglia, the myelination pattern, or the morphology of axons. Behavioural testing revealed an improvement of the spatial memory in the pre-onset treatment paradigm only.ConclusionOur results suggest to evaluate clinically a potential use of Pycnogenol in the prevention or in early stages of mild cognitive impairment (MCI) and AD. A2 - C1 - Bioorganic Chemistry ER - TY - JOUR ID - 687 TI - Profiling of Seed Proteome in Pea (Pisum sativum L.) Lines Characterized with High and Low Responsivity to Combined Inoculation with Nodule Bacteria and Arbuscular Mycorrhizal Fungi JO - Molecules PY - 2019 SP - 1603 AU - Mamontova, T. AU - Afonin, A. M. AU - Ihling, C. AU - Soboleva, A. AU - Lukasheva, E. AU - Sulima, A. S. AU - Shtark, O. Y. AU - Akhtemova, G. A. AU - Povydysh, M. N. AU - Sinz, A. AU - Frolov, A. AU - Zhukov, V. A. AU - Tikhonovich, I. A. AU - VL - 24 UR - DO - 10.3390/molecules24081603 AB - Legume crops represent the major source of food protein and contribute to human nutrition and animal feeding. An essential improvement of their productivity can be achieved by symbiosis with beneficial soil microorganisms—rhizobia (Rh) and arbuscular mycorrhizal (AM) fungi. The efficiency of these interactions depends on plant genotype. Recently, we have shown that, after simultaneous inoculation with Rh and AM, the productivity gain of pea (Pisum sativum L) line K-8274, characterized by high efficiency of interaction with soil microorganisms (EIBSM), was higher in comparison to a low-EIBSM line K-3358. However, the molecular mechanisms behind this effect are still uncharacterized. Therefore, here, we address the alterations in pea seed proteome, underlying the symbiosis-related productivity gain, and identify 111 differentially expressed proteins in the two lines. The high-EIBSM line K-8274 responded to inoculation by prolongation of seed maturation, manifested by up-regulation of proteins involved in cellular respiration, protein biosynthesis, and down-regulation of late-embryogenesis abundant (LEA) proteins. In contrast, the low-EIBSM line K-3358 demonstrated lower levels of the proteins, related to cell metabolism. Thus, we propose that the EIBSM trait is linked to prolongation of seed filling that needs to be taken into account in pulse crop breeding programs. The raw data have been deposited to the ProteomeXchange with identifier PXD013479. A2 - C1 - Bioorganic Chemistry ER - TY - JOUR ID - 656 TI - Biological activity and stability analyses of knipholone anthrone, a phenyl anthraquinone derivative isolated from Kniphofia foliosa Hochst. JO - J. Pharm. Biomed. Anal. PY - 2019 SP - 277-285 AU - Feilcke, R. AU - Arnouk, G. AU - Raphane, B. AU - Richard, K. AU - Tietjen, I. AU - Andrae-Marobela, K. AU - Erdmann, F. AU - Schipper, S. AU - Becker, K. AU - Arnold, N. AU - Frolov, A. AU - Reiling, N. AU - Imming, P. AU - Fobofou, S. A. T. AU - VL - 174 UR - DO - 10.1016/j.jpba.2019.05.065 AB - Knipholone (1) and knipholone anthrone (2), isolated from the Ethiopian medicinal plant Kniphofia foliosa Hochst. are two phenyl anthraquinone derivatives, a compound class known for biological activity. In the present study, we describe the activity of both 1 and 2 in several biological assays including cytotoxicity against four human cell lines (Jurkat, HEK293, SH-SY5Y and HT-29), antiplasmodial activity against Plasmodium falciparum 3D7 strain, anthelmintic activity against the model organism Caenorhabditis elegans, antibacterial activity against Aliivibrio fischeri and Mycobacterium tuberculosis and anti-HIV-1 activity in peripheral blood mononuclear cells (PBMCs) infected with HIV-1c. In parallel, we investigated the stability of knipholone (2) in solution and in culture media. Compound 1 displays strong cytotoxicity against Jurkat, HEK293 and SH-SY5Y cells with growth inhibition ranging from approximately 62–95% when added to cells at 50 μM, whereas KA (2) exhibits weak to strong activity with 26, 48 and 70% inhibition of cell growth, respectively. Both 1 and 2 possess significant antiplasmodial activity against Plasmodium falciparum 3D7 strain with IC50 values of 1.9 and 0.7 μM, respectively. These results complement previously reported data on the cytotoxicity and antiplasmodial activity of 1 and 2. Furthermore, compound 2 showed HIV-1c replication inhibition (growth inhibition higher than 60% at tested concentrations 0.5, 5, 15 and 50 μg/ml and an EC50 value of 4.3 μM) associated with cytotoxicity against uninfected PBMCs. The stability study based on preincubation, HPLC and APCI-MS (atmospheric-pressure chemical ionization mass spectrometry) analysis indicates that compound 2 is unstable in culture media and readily oxidizes to form compound 1. Therefore, the biological activity attributed to 2 might be influenced by its degradation products in media including 1 and other possible dimers. Hence, bioactivity results previously reported from this compound should be taken with caution and checked if they differ from those of its degradation products. To the best of our knowledge, this is the first report on the anti-HIV activity and stability analysis of compound 2. A2 - C1 - Bioorganic Chemistry ER - TY - JOUR ID - 684 TI - Nor-guanacastepene pigments from the Chilean mushroom Cortinarius pyromyxa JO - Phytochemistry PY - 2019 SP - 112048 AU - Lam, Y. T. H. AU - Palfner, G. AU - Lima, C. AU - Porzel, A. AU - Brandt, W. AU - Frolov, A. AU - Sultani, H. AU - Franke, K. AU - Wagner, C. AU - Merzweiler, K. AU - Wessjohann, L. A. AU - Arnold, N. AU - VL - 165 UR - DO - 10.1016/j.phytochem.2019.05.021 AB - For the first time, the pigment composition of basidiocarps from the Chilean mushroom Cortinarius pyromyxa was studied under various aspects like phylogeny, chemistry and antibiotic activity. A molecular biological study supports the monotypic position of C. pyromyxa in subgenus Myxacium, genus Cortinarius. Four undescribed diterpenoids, named pyromyxones A-D, were isolated from fruiting bodies of C. pyromyxa. Their chemical structures were elucidated based on comprehensive one- and two-dimensional NMR spectroscopic analysis, ESI-HRMS measurements, as well as X-ray crystallography. In addition, the absolute configurations of pyromyxones A-D were established with the aid of JH,H, NOESY spectra and quantum chemical CD calculation. The pyromyxones A-D possess the undescribed nor-guanacastane skeleton. Tested pyromyxones A, B, and D exhibit only weak activity against gram-positive Bacillus subtilis and gram-negative Aliivibrio fischeri as well as the phytopathogenic fungi Botrytis cinerea, Septoria tritici and Phytophthora infestans. A2 - C1 - Bioorganic Chemistry ER - TY - JOUR ID - 683 TI - Synthesis of a tubugi-1-toxin conjugate by a modulizable disulfide linker system with a neuropeptide Y analogue showing selectivity for hY1R-overexpressing tumor cells JO - Beilstein J. Org. Chem. PY - 2019 SP - 96-105 AU - Kufka, R. AU - Rennert, R. AU - Kaluđerović, G. N. AU - Weber, L. AU - Richter, W. AU - Wessjohann, L. A. AU - VL - 15 UR - DO - 10.3762/bjoc.15.11 AB - Tubugi-1 is a small cytotoxic peptide with picomolar cytotoxicity. To improve its cancer cell targeting, it was conjugated using a universal, modular disulfide derivative. This allowed conjugation to a neuropeptide-Y (NPY)-inspired peptide [K4(C-βA-),F7,L17,P34]-hNPY, acting as NPY Y1 receptor (hY1R)-targeting peptide, to form a tubugi-1–SS–NPY disulfide-linked conjugate. The cytotoxic impacts of the novel tubugi-1–NPY peptide–toxin conjugate, as well as of free tubugi-1, and tubugi-1 bearing the thiol spacer (liberated from tubugi-1–NPY conjugate), and native tubulysin A as reference were investigated by in vitro cell viability and proliferation screenings. The tumor cell lines HT-29, Colo320 (both colon cancer), PC-3 (prostate cancer), and in conjunction with RT-qPCR analyses of the hY1R expression, the cell lines SK-N-MC (Ewing`s sarcoma), MDA-MB-468, MDA-MB-231 (both breast cancer) and 184B5 (normal breast; chemically transformed) were investigated. As hoped, the toxicity of tubugi-1 was masked, with IC50 values decreased by ca. 1,000-fold compared to the free toxin. Due to intracellular linker cleavage, the cytotoxic potency of the liberated tubugi-1 that, however, still bears the thiol spacer (tubugi-1-SH) was restored and up to 10-fold higher compared to the entire peptide–toxin conjugate. The conjugate shows toxic selectivity to tumor cell lines overexpressing the hY1R receptor subtype like, e.g., the hard to treat triple-negative breast cancer MDA-MB-468 cells. A2 - C1 - Bioorganic Chemistry ER - TY - JOUR ID - 682 TI - Generation and Characterization of an Abcc1 Humanized Mouse Model (hABCC1flx/flx) with Knockout Capability JO - Mol. Pharmacol. PY - 2019 SP - 138-147 AU - Krohn, M. AU - Zoufal, V. AU - Mairinger, S. AU - Wanek, T. AU - Paarmann, K. AU - Brüning, T. AU - Eiriz, I. AU - Brackhan, M. AU - Langer, O. AU - Pahnke, J. AU - VL - 96 UR - DO - 10.1124/mol.119.115824 AB - ATP-binding cassette (ABC) transporters such as ABCB1 (P-glycoprotein), ABCC1 (MRP1), and ABCG2 (BCRP) are well known for their role in rendering cancer cells resistant to chemotherapy. Additionally, recent research provided evidence that, along with other ABC transporters (ABCA1 and ABCA7), they might be cornerstones to tackle neurodegenerative diseases. Overcoming chemoresistance in cancer, understanding drug-drug interactions, and developing efficient and specific drugs that alter ABC transporter function are hindered by a lack of in vivo research models, which are fully predictive for humans. Hence, the humanization of ABC transporters in mice has become a major focus in pharmaceutical and neurodegenerative research. Here, we present a characterization of the first Abcc1 humanized mouse line. To preserve endogenous expression profiles, we chose to generate a knockin mouse model that leads to the expression of a chimeric protein that is fully human except for one amino acid. We found robust mRNA and protein expression within all major organs analyzed (brain, lung, spleen, and kidney). Furthermore, we demonstrate the functionality of the expressed human ABCC1 protein in brain and lungs using functional positron emission tomography imaging in vivo. Through the introduction of loxP sites, we additionally enabled this humanized mouse model for highly sophisticated studies involving cell type–specific transporter ablation. Based on our data, the presented mouse model appears to be a promising tool for the investigation of cell-specific ABCC1 function. It can provide a new basis for better translation of preclinical research. A2 - C1 - Bioorganic Chemistry ER - TY - JOUR ID - 681 TI - The hop-derived prenylflavonoid isoxanthohumol inhibits the formation of lung metastasis in B16-F10 murine melanoma model JO - Food Chem. Toxicol. PY - 2019 SP - 257-268 AU - Krajnović, T. AU - Drača, D. AU - Kaluđerović, G. N. AU - Dunđerović, D. AU - Mirkov, I. AU - Wessjohann, L. A. AU - Maksimović-Ivanić, D. AU - Mijatović, S. AU - VL - 129 UR - DO - 10.1016/j.fct.2019.04.046 AB - Isoxanthohumol (IXN), a prenylflavonoid from hops and beer, gained increasing attention as a potential chemopreventive agent. In the present study, IXN antimetastatic potential in vitro against the highly invasive melanoma cell line B16-F10 and in vivo in a murine metastatic model was investigated. Melanoma cell viability was diminished in a dose-dependent manner following the treatment with IXN. This decrease was a consequence of autophagy and caspase-dependent apoptosis. Additionally, the dividing potential of highly proliferative melanoma cells was dramatically affected by this isoflavanone, which was in correlation with an abrogated cell colony forming potential, indicating changes in their metastatic features. Concordantly, IXN promoted strong suppression of the processes that define metastasis– cell adhesion, invasion, and migration. Further investigation at the molecular level revealed that the abolished metastatic potential of a melanoma subclone was due to disrupted integrin signaling. Importantly, these results were reaffirmed in vivo where IXN inhibited the development of lung metastatic foci in tumor-challenged animals. The results of the present study may highlight the beneficial effects of IXN on melanoma as the most aggressive type of skin cancer and will hopefully shed a light on the possible use of this prenylflavonoid in the treatment of metastatic malignancies. A2 - C1 - Bioorganic Chemistry ER - TY - CHAP ID - 33 TI - Ion Homeostasis Response to Nutrient-Deficiency Stress in Plants T2 - Cell Growth PB - PY - 2019 SP - 1-23 AU - Osmolovskaya, N. AU - Shumilina, J. AU - Bureiko, K. AU - Chantseva, V. AU - Bilova, T. AU - Kuchaeva, L. AU - Laman, N. AU - Wessjohann, L. A. AU - Frolov, A. AU - VL - UR - SN - 978-1-78985-311-7 DO - 10.5772/intechopen.89398 AB - A crucial feature of plant performance is its strong dependence on the availability of essential mineral nutrients, affecting multiple vital functions. Indeed, mineral-nutrient deficiency is one of the major stress factors affecting plant growth and development. Thereby, nitrogen and potassium represent the most abundant mineral contributors, critical for plant survival. While studying plant responses to nutrient deficiency, one should keep in mind that mineral nutrients, along with their specific metabolic roles, are directly involved in maintaining cell ion homeostasis, which relies on a finely tuned equilibrium between cytosolic and vacuolar ion pools. Therefore, in this chapter we briefly summarize the role of the ion homeostasis system in cell responses to environmental deficiency of nitrate and potassium ions. Special attention is paid to the implementation of plant responses via NO3− and K+ root transport and regulation of ion distribution in cell compartments. These responses are strongly dependent on plant species, as well as severity and duration of nutrient deficiency. A2 - Vikas, B. & Fasullo, M., eds. C1 - Bioorganic Chemistry ER - TY - JOUR ID - 2529 TI - Methodology of Drought Stress Research: Experimental Setup and Physiological Characterization JO - Preprints PY - 2018 SP - AU - Osmolovskaya, N. AU - Shumilina, J. AU - Kim, A. AU - Didio, A. AU - Grishina, T. AU - Bilova, T. AU - Keltsieva, O. A. AU - Zhukov, V. AU - Tikhonovich, I. AU - Tarakhovskaya, E. AU - Wessjohann, L. A. AU - Frolov, A. AU - VL - UR - DO - 10.20944/preprints201812.0145.v1 AB - Drought is one of the major stress factors affecting growth and development of plants. In this context, drought-related losses of crop plant productivity impede sustainable agriculture all over the world. In general, plants responses to water deficit by multiple physiological and metabolic adaptations at the molecular, cellular and organism levels. To understand the underlying mechanisms of drought tolerance, adequate stress models and arrays of reliable stress markers are required. Therefore, in this review we comprehensively address currently available models of drought stress, based on culturing plants in soil, hydroponic or agar culture. These experimental setups give access to different aspects of plant response to drought, like decrease of tissue water potential, reduction of stomata conductance and photosynthesis efficiency, accumulation of low-molecular weight solutes (metabolic adjustment) and drought protective proteins. Till now, this pattern of markers was successfully extended to the methods of enzyme chemistry, molecular biology and omics techniques. Thus, conventional tests can be efficiently complemented by determination of phytohormone and reactive oxygen species (ROS) contents, activities of antioxidant enzymes, as well as comprehensive profiling of transcriptome, proteome and metabolome. A2 - C1 - Bioorganic Chemistry ER - TY - JOUR ID - 2525 TI - Proteome Map of Pea (Pisum Sativum L.) Embryos Containing Different Amounts of Residual Chlorophylls JO - Preprints PY - 2018 SP - AU - Mamontova, T. AU - Lukasheva, E. AU - Mavropolo-Stolyarenko, G. AU - Proksch, C. AU - Bilova, T. AU - Kim, A. AU - Babakov, V. AU - Grishina, T. AU - Hoehenwarter, W. AU - Medvedev, S. AU - Smolikova, G. AU - Frolov, A. AU - VL - UR - DO - 10.20944/preprints201812.0069.v1 AB - Due to low culturing costs and high seed protein contents, legumes represent the main global source of food protein. Pea (Pisum sativum L.) is one of the major economically important legume crops, impacting both animal feed and human nutrition. Therefore, the quality of pea seeds needs to be ensured in the context of sustainable crop production and nutritional efficiency. Obviously, changes in seed protein patterns might directly affect both of these aspects. Thus, here we address the pea seed proteome in more detail and provide, to the best of our knowledge, the most comprehensive annotation of the functions and intracellular localization of pea seed proteins. Accordingly, 1938 and 1989 non-redundant proteins were identified in yellow and green pea seeds, in total. Only 35 and 44 proteins, respectively, could be additionally identified after protamine sulfate precipitation (PSP) potentially indicating the high efficiency of our experimental workflow. In total 981 protein groups could be assigned to 34 functional classes, which were to a large extent differentially represented in yellow and green seeds. Closer analysis of these differences by processing of the data in KEGG and String databases revealed their possible relation to a higher metabolic status and reduced longevity of green seeds. A2 - C1 - Bioorganic Chemistry ER - TY - JOUR ID - 818 TI - Diversity Driven Decoration and Ligation of Fullerene by Ugi and Passerini Multicomponent Reactions JO - Chem.-Eur. J. PY - 2018 SP - 9788-9793 AU - Ravanello, B. B. AU - Seixas, N. AU - Rodrigues, O. E. D. AU - da Silva, R. S. AU - Villetti, M. A. AU - Frolov, A. AU - Rivera, D. G. AU - Westermann, B. AU - VL - 24 UR - DO - 10.1002/chem.201802414 AB - Aiming at providing an efficient and versatile method for the diversity‐oriented decoration and ligation of fullerenes, we report the first C60 derivatization strategy based on isocyanide‐multicomponent reactions (I‐MCRs). The approach comprises the use of Passerini and Ugi reactions for assembling pseudo‐peptidic scaffolds (i.e., N‐alkylated and depsipeptides, peptoids) on carboxylic acid‐functionalized fullerenes. The method showed wide substrate scope for the oxo and isocyanide components, albeit the Ugi reaction proved efficient only for aromatic amines. The approach was successfully employed for the ligation of oligopeptides and polyethyleneglycol chains (PEG) to C60, as well as for the construction of bis‐antennary as well as PEG‐tethered dimeric fullerenes. The quantum yields for the formation of 1O2 was remarkable for the selected compounds analyzed. A2 - C1 - Bioorganic Chemistry ER - TY - JOUR ID - 817 TI - Comparative analysis of Hibiscus sabdariffa (roselle) hot and cold extracts in respect to their potential for α-glucosidase inhibition JO - Food Chem. PY - 2018 SP - 236-244 AU - Rasheed, D. M. AU - Porzel, A. AU - Frolov, A. AU - El Seedi, H. R. AU - Wessjohann, L. A. AU - Farag, M. A. AU - VL - 250 UR - DO - 10.1016/j.foodchem.2018.01.020 AB - Roselle (Hibiscus sabdariffa) is a functional food with potential health benefits, consumed either as hot or cold beverage. To ensure quality control of its various products, accurate measurement of active metabolites is warranted. Herein, we propose a combination of ultra-high performance liquid chromatography-mass spectrometry (UHPLC-MS) and nuclear magnetic resonance (NMR) analytical platforms for the untargeted characterization of metabolites in two roselle cultivars, Aswan and Sudan-1. The analyses revealed 33 metabolites, including sugars, flavonoids, anthocyanins, phenolic and aliphatic organic acids. Their relative contents in cultivars were assessed via principle component analysis (PCA) and orthogonal projection to latent structures analysis (OPLS). Impact of the different extraction methods (decoction, infusion and maceration) was compared by quantitative 1H NMR spectroscopy, revealing cold maceration to be optimal for preserving anthocyanins, whereas infusion was more suited for recovering organic acids. The metabolite pattern revealed by the different extraction methods was found in good correlation for their ability to inhibit α-glucosidase enzyme. A2 - C1 - Bioorganic Chemistry ER - TY - JOUR ID - 811 TI - Methodology of Drought Stress Research: Experimental Setup and Physiological Characterization JO - Int. J. Mol. Sci. PY - 2018 SP - 4089 AU - Osmolovskaya, N. AU - Shumilina, J. AU - Kim, A. AU - Didio, A. AU - Grishina, T. AU - Bilova, T. AU - Keltsieva, O. A. AU - Zhukov, V. AU - Tikhonovich, I. AU - Tarakhovskaya, E. AU - Frolov, A. AU - Wessjohann, L. A. AU - VL - 19 UR - DO - 10.3390/ijms19124089 AB - Drought is one of the major stress factors affecting the growth and development of plants. In this context, drought-related losses of crop plant productivity impede sustainable agriculture all over the world. In general, plants respond to water deficits by multiple physiological and metabolic adaptations at the molecular, cellular, and organism levels. To understand the underlying mechanisms of drought tolerance, adequate stress models and arrays of reliable stress markers are required. Therefore, in this review we comprehensively address currently available models of drought stress, based on culturing plants in soil, hydroponically, or in agar culture, and critically discuss advantages and limitations of each design. We also address the methodology of drought stress characterization and discuss it in the context of real experimental approaches. Further, we highlight the trends of methodological developments in drought stress research, i.e., complementing conventional tests with quantification of phytohormones and reactive oxygen species (ROS), measuring antioxidant enzyme activities, and comprehensively profiling transcriptome, proteome, and metabolome. A2 - C1 - Bioorganic Chemistry ER - TY - JOUR ID - 805 TI - Naturally occurring compounds in differentiation based therapy of cancer JO - Biotechnol. Adv. PY - 2018 SP - 1622-1632 AU - Mijatović, S. AU - Bramanti, A. AU - Nicoletti, F. AU - Fagone, P. AU - Kaluđerović, G. N. AU - Maksimović-Ivanić, D. AU - VL - 36 UR - DO - 10.1016/j.biotechadv.2018.04.001 AB - Differentiation of cancer cells entails the reversion of phenotype from malignant to the original. The conversion to cell type characteristic for another tissue is named transdifferentiation. Differentiation/transdifferentiation of malignant cells in high grade tumor mass could serve as a nonaggressive approach that potentially limits tumor progression and augments chemosensitivity. While this therapeutic strategy is already being used for treatment of hematological cancers, its feasibility for solid malignancies is still debated. We will presently discuss the natural compounds that show these properties, with focus on anthraquinones from Aloe vera, Senna, Rheum sp. and hop derived prenylflavonoids. A2 - C1 - Bioorganic Chemistry ER - TY - JOUR ID - 801 TI - Protein Carbonylation and Glycation in Legume Nodules JO - Plant Physiol. PY - 2018 SP - 1510-1528 AU - Matamoros, M. A. AU - Kim, A. AU - Peñuelas, M. AU - Ihling, C. AU - Griesser, E. AU - Hoffmann, R. AU - Fedorova, M. AU - Frolov, A. AU - Becana, M. AU - VL - 177 UR - DO - 10.1104/pp.18.00533 AB - Nitrogen fixation is an agronomically and environmentally important process catalyzed by bacterial nitrogenase within legume root nodules. These unique symbiotic organs have high metabolic rates and produce large amounts of reactive oxygen species that may modify proteins irreversibly. Here, we examined two types of oxidative posttranslational modifications of nodule proteins: carbonylation, which occurs by direct oxidation of certain amino acids or by interaction with reactive aldehydes arising from cell membrane lipid peroxides; and glycation, which results from the reaction of Lys and Arg residues with reducing sugars or their auto-oxidation products. We used a strategy based on the enrichment of carbonylated peptides by affinity chromatography followed by liquid chromatography-tandem mass spectrometry to identify 369 oxidized proteins in bean (Phaseolus vulgaris) nodules. Of these, 238 corresponded to plant proteins and 131 to bacterial proteins. Lipid peroxidation products induced most carbonylation sites. This study also revealed that carbonylation has major effects on two key nodule proteins. Metal-catalyzed oxidation caused inactivation of malate dehydrogenase and aggregation of leghemoglobin. In addition, numerous glycated proteins were identified in vivo, including three key nodule proteins: sucrose synthase, glutamine synthetase, and glutamate synthase. Label-free quantification identified 10 plant proteins and 18 bacterial proteins as age-specifically glycated. Overall, our results suggest that the selective carbonylation or glycation of crucial proteins involved in nitrogen metabolism, transcriptional regulation, and signaling may constitute a mechanism to control cell metabolism and nodule senescence. A2 - C1 - Bioorganic Chemistry ER - TY - JOUR ID - 800 TI - Proteome Map of Pea (Pisum sativum L.) Embryos Containing Different Amounts of Residual Chlorophylls JO - Int. J. Mol. Sci. PY - 2018 SP - 4066 AU - Mamontova, T. AU - Lukasheva, E. AU - Mavropolo-Stolyarenko, G. AU - Proksch, C. AU - Bilova, T. AU - Kim, A. AU - Babakov, V. AU - Grishina, T. AU - Hoehenwarter, W. AU - Medvedev, S. AU - Smolikova, G. AU - Frolov, A. AU - VL - 19 UR - DO - 10.3390/ijms19124066 AB - Due to low culturing costs and high seed protein contents, legumes represent the main global source of food protein. Pea (Pisum sativum L.) is one of the major legume crops, impacting both animal feed and human nutrition. Therefore, the quality of pea seeds needs to be ensured in the context of sustainable crop production and nutritional efficiency. Apparently, changes in seed protein patterns might directly affect both of these aspects. Thus, here, we address the pea seed proteome in detail and provide, to the best of our knowledge, the most comprehensive annotation of the functions and intracellular localization of pea seed proteins. To address possible intercultivar differences, we compared seed proteomes of yellow- and green-seeded pea cultivars in a comprehensive case study. The analysis revealed totally 1938 and 1989 nonredundant proteins, respectively. Only 35 and 44 proteins, respectively, could be additionally identified after protamine sulfate precipitation (PSP), potentially indicating the high efficiency of our experimental workflow. Totally 981 protein groups were assigned to 34 functional classes, which were to a large extent differentially represented in yellow and green seeds. Closer analysis of these differences by processing of the data in KEGG and String databases revealed their possible relation to a higher metabolic status and reduced longevity of green seeds. A2 - C1 - Bioorganic Chemistry ER - TY - JOUR ID - 799 TI - Influence of breast cancer resistance protein and P-glycoprotein on tissue distribution and excretion of Ko143 assessed with PET imaging in mice JO - Eur. J. Pharm. Sci. PY - 2018 SP - 212-222 AU - Mairinger, S. AU - Zoufal, V. AU - Wanek, T. AU - Traxl, A. AU - Filip, T. AU - Sauberer, M. AU - Stanek, J. AU - Kuntner, C. AU - Pahnke, J. AU - Müller, M. AU - Langer, O. AU - VL - 115 UR - DO - 10.1016/j.ejps.2018.01.034 AB - Ko143 is a reference inhibitor of the adenosine triphosphate-binding cassette (ABC) transporter breast cancer resistance protein (humans: ABCG2, rodents: Abcg2) for in vitro and in vivo use. Previous in vitro data indicate that Ko143 binds specifically to ABCG2/Abcg2, suggesting a potential utility of Ko143 as a positron emission tomography (PET) tracer to assess the density (abundance) of ABCG2 in different tissues. In this work we radiolabeled Ko143 with carbon-11 (11C) and performed small-animal PET experiments with [11C]Ko143 in wild-type, Abcg2(−/−), Abcb1a/b(−/−) and Abcb1a/b(−/−)Abcg2(−/−) mice to assess the influence of Abcg2 and Abcb1a/b on tissue distribution and excretion of [11C]Ko143.[11C]Ko143 was extensively metabolized in vivo and unidentified radiolabeled metabolites were found in all investigated tissues. We detected no significant differences between wild-type and Abcg2(−/−) mice in the distribution of [11C]Ko143-derived radioactivity to Abcg2-expressing organs (brain, liver and kidney). [11C]Ko143 and possibly its radiolabeled metabolites were transported by Abcb1a and not by Abcg2 at the mouse blood-brain barrier. [11C]Ko143-derived radioactivity underwent both hepatobiliary and urinary excretion, with Abcg2 playing a possible role in mediating the transport of radiolabeled metabolites of [11C]Ko143 from the kidney into urine. Experiments in which a pharmacologic dose of unlabeled Ko143 (10 mg/kg) was co-administered with [11C]Ko143 revealed pronounced effects of the vehicle used for Ko143 formulation (containing polyethylene glycol 300 and polysorbate 80) on radioactivity distribution to the brain and the liver, as well as on hepatobiliary and urinary excretion of radioactivity.Our results highlight the challenges associated with the development of PET tracers for ABC transporters and emphasize that inhibitory effects of pharmaceutical excipients on membrane transporters need to be considered when performing in vivo drug-drug interaction studies. Finally, our study illustrates the power of small-animal PET to assess the interaction of drug molecules with membrane transporters on a whole body level. A2 - C1 - Bioorganic Chemistry ER - TY - JOUR ID - 797 TI - Loss of epithelium-specific GPx2 results in aberrant cell fate decisions during intestinal differentiation JO - Oncotarget PY - 2018 SP - 539-552 AU - Lennicke, C. AU - Rahn, J. AU - Wickenhauser, C. AU - Lichtenfels, R. AU - Müller, A. S. AU - Wessjohann, L. A. AU - Kipp, A. P. AU - Seliger, B. AU - VL - 9 UR - DO - 10.18632/oncotarget.22640 AB - The selenoprotein glutathione peroxidase 2 (GPx2) is expressed in the epithelium of the gastrointestinal tract, where it is thought to be involved in maintaining mucosal homeostasis. To gain novel insights into the role of GPx2, proteomic profiles of colonic tissues either derived from wild type (WT) or GPx2 knockout (KO) mice, maintained under selenium (Se) deficiency or adequate Se supplementation conditions were established and analyzed. Amongst the panel of differentially expressed proteins, the calcium-activated chloride channel regulator 1 (CLCA1) was significantly down-regulated in GPx2 KO versus WT mice regardless of the given Se status. Moreover, transcript levels of the isoforms CLCA2 and CLCA3 showed a similar expression pattern. In the intestine, CLCA1 is usually restricted to mucin-producing goblet cells. However, although -SeKO mice had the highest numbers of goblet cells as confirmed by significantly enhanced mRNA expression levels of the goblet cell marker mucin-2, the observed expression pattern suggests that GPx2 KO goblet cells might be limited in synthesizing CLCA1. Furthermore, transcript levels of differentiation markers such as chromogranin-1 (Chga) for enteroendocrine cells and leucine-rich repeat-containing G-protein coupled receptor 5 (Lgr5) for stem cells were also downregulated in GPx2 KO mice. Moreover, this was accompanied by a downregulation of the mRNA expression levels of the intestinal hormones glucagon-like peptide 1 (Glp1), ghrelin (Ghrl) and somatostatin (Sst). Thus, it seems that GPx2 might be important for the modulation of cell fate decisions in the murine intestinal epithelium. A2 - C1 - Bioorganic Chemistry ER - TY - JOUR ID - 796 TI - Survival Associations Using Perfusion and Diffusion Magnetic Resonance Imaging in Patients With Histologic and Genetic Defined Diffuse Glioma World Health Organization Grades II and III JO - J. Comput. Assist. Tomo. PY - 2018 SP - 807-815 AU - Latysheva, A. AU - Eeg Emblem, K. AU - Server, A. AU - Brandal, P. AU - Meling, T. R. AU - Pahnke, J. AU - Hald, J. K. AU - VL - 42 UR - DO - 10.1097/RCT.0000000000000742 AB - Objective According to the new World Health Organization 2016 classification for tumors of the central nervous system, 1p/19q codeletion defines the genetic hallmark that differentiates oligodendrogliomas from diffuse astrocytomas. The aim of our study was to evaluate whether relative cerebral blood volume (rCBV) and apparent diffusion coefficient (ADC) histogram analysis can stratify survival in adult patients with genetic defined diffuse glioma grades II and III.Methods Sixty-seven patients with untreated diffuse gliomas World Health Organization grades II and III and known 1p/19q codeletion status were included retrospectively and analyzed using ADC and rCBV maps based on whole-tumor volume histograms. Overall survival and progression-free survival (PFS) were analyzed by using Kaplan-Meier and Cox survival analyses adjusted for known survival predictors.Results Significant longer PFS was associated with homogeneous rCBV distribution–higher rCBVpeak (median, 37 vs 26 months; hazard ratio [HR], 3.2; P = 0.02) in patients with astrocytomas, and heterogeneous rCBV distribution–lower rCBVpeak (median, 46 vs 37 months; HR, 5.3; P < 0.001) and higher rCBVmean (median, 44 vs 39 months; HR, 7.9; P = 0.003) in patients with oligodendrogliomas. Apparent diffusion coefficient parameters (ADCpeak, ADCmean) did not stratify PFS and overall survival.Conclusions Tumors with heterogeneous perfusion signatures and high average values were associated with longer PFS in patients with oligodendrogliomas. On the contrary, heterogeneous perfusion distribution was associated with poor outcome in patients with diffuse astrocytomas. A2 - C1 - Bioorganic Chemistry ER - TY - JOUR ID - 795 TI - ABCA7 Downregulation Modifies Cellular Cholesterol Homeostasis and Decreases Amyloid-β Peptide Efflux in an in vitro Model of the Blood-Brain Barrier JO - J. Alzheimers Dis. PY - 2018 SP - 1195-1211 AU - Lamartinière, Y. AU - Boucau, M.-C. AU - Dehouck, L. AU - Krohn, M. AU - Pahnke, J. AU - Candela, P. AU - Gosselet, F. AU - Fenart, L. AU - VL - 64 UR - DO - 10.3233/JAD-170883 AB - The role of ABCA7 in brain homeostasis and Alzheimer’s disease (AD) is currently under intense scrutiny, since it has been reported that polymorphisms in the Abca7 gene and a loss of function of the protein are closely linked to excessive accumulation of amyloid peptides and disturbed cholesterol homeostasis. The blood-brain barrier (BBB), which isolates the brain from the blood compartment, is involved in both of these processes. We therefore hypothesized that ABCA7 downregulation might affect cholesterol and amyloid exchanges at the BBB. Using siRNA and primary cultures of mouse endothelial cells purified from brain microvessels and seeded on Transwell ® inserts, we investigated the role of ABCA7 in cholesterol and amyloid exchanges across the BBB. Our results showed that a decrease in ABCA7 expression at the BBB provokes in vitro a reduction in ABCA1 expression and a decrease in APOE secretion. In vitro, these decreases reduce cholesterol exchange across the BBB, particularly for high-density lipoproteins and ApoA-I particles. When ABCA7 was absent, we observed a reduction in Aβ peptide basolateral-to-apical transport in the presence of ApoA-I, with non-significant changes in the expression levels of Rage, Lrp1, Abcb1, Abcc1, and Abcg2. Our study in murine BBB model highlighted a putative new role for ABCA7 in AD via the protein’s involvement in cholesterol metabolism and amyloid clearance at the BBB. A2 - C1 - Bioorganic Chemistry ER - TY - JOUR ID - 794 TI - Humanization of the blood–brain barrier transporter ABCB1 in mice disrupts genomic locus — lessons from three unsuccessful approaches JO - Eur. J. Microbiol. Immunol. PY - 2018 SP - 78-86 AU - Krohn, M. AU - Wanek, T. AU - Menet, M.-C. AU - Noack, A. AU - Declèves, X. AU - Langer, O. AU - Löscher, W. AU - Pahnke, J. AU - VL - 8 UR - DO - 10.1556/1886.2018.00008 AB - ATP-binding cassette (ABC) transporters are of major importance for the restricted access of toxins and drugs to the human body. At the body's barrier tissues like the blood–brain barrier, these transporters are highly represented. Especially, ABCB1 (P-glycoprotein) has been a priority target of pharmaceutical research, for instance, to aid chemotherapy of cancers, therapy resistant epilepsy, and lately even neurodegenerative diseases. To improve translational research, the humanization of mouse genes has become a popular tool although, like recently seen for Abcb1, not all approaches were successful. Here, we report the characterization of another unsuccessful commercially available ABCB1 humanized mouse strain. In vivo assessment of transporter activity using positron emission tomography imaging revealed a severe reduction of ABCB1 function in the brain of these mice. Analyses of brain mRNA and protein expression showed that the murine Abcb1a gene is still expressed in homozygous humanized animals while expression of the human gene is minimal. Promoter region analyses underpinned that the introduced human gene might dysregulate normal expression and provided insights into the regulation of both transcription and translation of Abcb1a. We conclude that insertion of the human coding DNA sequence (CDS) into exon 3 instead of exon 2 most probably represents a more promising strategy for Abcb1a humanization. A2 - C1 - Bioorganic Chemistry ER - TY - JOUR ID - 777 TI - The effect of simulated microgravity on the Brassica napus seedling proteome JO - Funct. Plant Biol. PY - 2018 SP - 440-452 AU - Frolov, A. AU - Didio, A. AU - Ihling, C. AU - Chantzeva, V. AU - Grishina, T. AU - Hoehenwarter, W. AU - Sinz, A. AU - Smolikova, G. AU - Bilova, T. AU - Medvedev, S. AU - VL - 45 UR - DO - 10.1071/FP16378 AB - The magnitude and the direction of the gravitational field represent an important environmental factor affecting plant development. In this context, the absence or frequent alterations of the gravity field (i.e. microgravity conditions) might compromise extraterrestrial agriculture and hence space inhabitation by humans. To overcome the deleterious effects of microgravity, a complete understanding of the underlying changes on the macromolecular level is necessary. However, although microgravity-related changes in gene expression are well characterised on the transcriptome level, proteomic data are limited. Moreover, information about the microgravity-induced changes in the seedling proteome during seed germination and the first steps of seedling development is completely missing. One of the valuable tools to assess gravity-related issues is 3D clinorotation (i.e. rotation in two axes). Therefore, here we address the effects of microgravity, simulated by a two-axial clinostat, on the proteome of 24- and 48-h-old seedlings of oilseed rape (Brassica napus L.). The liquid chromatography-MS-based proteomic analysis and database search revealed 95 up- and 38 downregulated proteins in the tryptic digests obtained from the seedlings subjected to simulated microgravity, with 42 and 52 annotations detected as being unique for 24- and 48-h treatment times, respectively. The polypeptides involved in protein metabolism, transport and signalling were annotated as the functional groups most strongly affected by 3-D clinorotation. A2 - C1 - Bioorganic Chemistry ER - TY - JOUR ID - 776 TI - Mining seed proteome: from protein dynamics to modification profiles JO - Biol. Commun. PY - 2018 SP - 43-58 AU - Frolov, A. AU - Mamontova, T. AU - Ihling, C. AU - Lukasheva, E. AU - Bankin, M. AU - Chantseva, V. AU - Vikhnina, M. AU - Soboleva, A. AU - Shumilina, J. AU - Mavropolo-Stolyarenko, G. AU - Grishina, T. AU - Osmolovskaya, N. AU - Zhukov, V. AU - Hoehenwarter, W. AU - Sinz, A. AU - Tikhononovich, I. AU - Wessjohann, L. AU - Bilova, T. AU - Smolikova, G. AU - Medvedev, S. AU - VL - 63 UR - DO - 10.21638/spbu03.2018.106 AB - In the modern world, crop plants represent a major source of daily consumed foods. Among them, cereals and legumes — i.e. the crops accumulating oils, carbohydrates and proteins in their seeds — dominate in European agriculture, tremendously impacting global protein consumption and biodiesel production. Therefore, the seeds of crop plants attract the special attention of biologists, biochemists, nutritional physiologists and food chemists. Seed development and germination, as well as age- and stress-related changes in their viability and nutritional properties, can be addressed by a variety of physiological and biochemical methods. In this context, the methods of functional genomics can be applied to address characteristic changes in seed metabolism, which can give access to stress-resistant genotypes. Among these methods, proteomics is one of the most effective tools, allowing mining metabolism changes on the protein level. Here we discuss the main methodological approaches of seed proteomics in the context of physiological changes related to environmental stress and ageing. We provide a comprehensive comparison of gel- and chromatographybased approaches with a special emphasis on advantages and disadvantages of both strategies in characterization of the seed proteome. A2 - C1 - Cell and Metabolic Biology; Bioorganic Chemistry ER - TY - JOUR ID - 775 TI - Derivatization of Methylglyoxal for LC-ESI-MS Analysis—Stability and Relative Sensitivity of Different Derivatives JO - Molecules PY - 2018 SP - 2994 AU - Fritzsche, S. AU - Billig, S. AU - Rynek, R. AU - Abburi, R. AU - Tarakhovskaya, E. AU - Leuner, O. AU - Frolov, A. AU - Birkemeyer, C. AU - VL - 23 UR - DO - 10.3390/molecules23112994 AB - The great research interest in the quantification of reactive carbonyl compounds (RCCs), such as methylglyoxal (MGO) in biological and environmental samples, is reflected by the fact that several publications have described specific strategies to perform this task. Thus, many reagents have also been reported for the derivatization of RCCs to effectively detect and quantify the resulting compounds using sensitive techniques such as liquid chromatography coupled with mass spectrometry (LC-MS). However, the choice of the derivatization protocol is not always clear, and a comparative evaluation is not feasible because detection limits from separate reports and determined with different instruments are hardly comparable. Consequently, for a systematic comparison, we tested 21 agents in one experimental setup for derivatization of RCCs prior to LC-MS analysis. This consisted of seven commonly employed reagents and 14 similar reagents, three of which were designed and synthesized by us. All reagents were probed for analytical responsiveness of the derivatives and stability of the reaction mixtures. The results showed that derivatives of 4-methoxyphenylenediamine and 3-methoxyphenylhydrazine—reported here for the first time for derivatization of RCCs—provided a particularly high responsiveness with ESI-MS detection. We applied the protocol to investigate MGO contamination of laboratory water and show successful quantification in a lipoxidation experiment. In summary, our results provide valuable information for scientists in establishing accurate analysis of RCCs. A2 - C1 - Bioorganic Chemistry ER - TY - JOUR ID - 759 TI - Apoptosis caused by triterpenes and phytosterols and antioxidant activity of an enriched flavonoid extract and from Passiflora mucronata JO - Anti-Cancer Agents Med. Chem. PY - 2018 SP - 1405-1416 AU - da Silva, I. C. V. AU - Kaluderovic, G. AU - de Oliveira, P. F. AU - Guimaraes, D. O. AU - Quaresma, C. H. AU - Porzel, A. AU - Muzitano, M. F. AU - Wessjohann, L. A. AU - Leal, I. C. R. AU - VL - 18 UR - DO - 10.2174/1871520618666180315090949 AB - Background: P. mucronata (Pm) comes from South America, Brazil and is characterized as “Maracujá de Restinga”. It is used in folk medicine for its soothing properties and in treating insomnia. Objective: The present study for the first time analyzed the antioxidant and cytotoxicity of the hydroalcoholic leaves extract and fractions from Pm. Method: The cytotoxicity test will be evaluated by different assays (MTT and CV) against human prostate cancer (PC3) and mouse malignant melanoma (B16F10) cell lines, and the antioxidant test by DPPH method. Results: β-Amyrin, oleanolic acid, β-sitosterol and stigmasterol were isolated of the most active, hexane fraction. These substances were tested against the tumor cell lines: β-sitosterol and stigmasterol showed the most relevant activity to PC3 in CV assay and, oleanolic acid to B16F10 by the MTT assay. In addition, it was possible to indicate that the mode of cell death for stigmasterol, presumably is apoptosis. In terms of antioxidant activity, the hydroalcoholic leaves extract presented higher activity (EC50 133.3 μg/mL) compared to the flower (EC50 152.3 μg/mL) and fruit (EC50 207.9 μg/mL) extracts. By the HPLC-MS, it was possible to identify the presence of flavones in the leaf extract (isoschaftoside, schaftoside, isovitexin, vitexin, isoorientin, orientin). Conclusions: P. mucronata hexane fraction showed promising cytotoxic effect against cancer cell lines, and stigmasterol contributes to this activity, inducing apoptosis of these cells. Furthermore, as other Passiflora species, Pm extract showed antioxidant activity and flavones are its major phenolic compounds. A2 - C1 - Bioorganic Chemistry ER - TY - JOUR ID - 756 TI - Intrinsic Xenobiotic Resistance of the Intestinal Stem Cell Niche JO - Dev. Cell PY - 2018 SP - 681-695.e5 AU - Chee, Y. C. AU - Pahnke, J. AU - Bunte, R. AU - Adsool, V. A. AU - Madan, B. AU - Virshup, D. M. AU - VL - 46 UR - DO - 10.1016/j.devcel.2018.07.023 AB - The gut absorbs dietary nutrients and provides a barrier to xenobiotics and microbiome metabolites. To cope with toxin exposures, the intestinal epithelium is one of the most rapidly proliferating tissues in the body. The stem cell niche supplies essential signaling factors including Wnt proteins secreted by subepithelial myofibroblasts. Unexpectedly, therapeutically effective doses of orally administered PORCN inhibitors that block all Wnt secretion do not affect intestinal homeostasis. We find that intestinal myofibroblasts are intrinsically resistant to multiple xenobiotics, including PORCN inhibitors and the anthracycline antibiotic doxorubicin. These myofibroblasts have high expression of a subset of drug transporters; knockout of Mrp1/Abcc1 enhances drug sensitivity. Tamoxifen administration to Rosa26CreERT2;mT/mG mice visually highlights the drug-resistant intestinal stromal compartment and identifies small populations of drug-resistant cells in lung, kidney, and pancreatic islets. Xenobiotic resistance of the Wnt-producing myofibroblasts can protect the intestinal stem cell niche in the face of an unpredictable environment. A2 - C1 - Bioorganic Chemistry ER - TY - JOUR ID - 753 TI - Corrigendum to “Morphometric analysis of the cerebral expression of ATP-binding cassette transporter protein ABCB1 in chronic schizophrenia: Circumscribed deficits in the habenula” [Schizophr. Res. 2016 Nov;177(1–3):52–58] JO - Schizophr. Res. PY - 2018 SP - 622-623 AU - Bernstein, H. AU - Hildebrandt, J. AU - Dobrowolny, H. AU - Steiner, J. AU - Bogerts, B. AU - Pahnke, J. AU - VL - 197 UR - DO - 10.1016/j.schres.2018.03.036 AB - A2 - C1 - Bioorganic Chemistry ER - TY - JOUR ID - 831 TI - Development and validation of LC/APCI-MS method for the quantification of oat ceramides in skin permeation studies JO - Anal. Bioanal. Chem. PY - 2018 SP - 4775-4785 AU - Tessema, E. N. AU - Gebre-Mariam, T. AU - Frolov, A. AU - Wohlrab, J. AU - Neubert, R. H. H. AU - VL - 410 UR - DO - 10.1007/s00216-018-1162-z AB - Ceramides (CERs) are the backbone of the intercellular lipid lamellae of the stratum corneum (SC), the outer layer of the skin. Skin diseases such as atopic dermatitis, psoriasis, and aged skin are characterized by dysfunctional skin barrier and dryness which are associated with reduced levels of CERs. Replenishing the depleted epidermal CERs with exogenous CERs has been shown to have beneficial effects in improving the skin barrier and hydration. The exogenous CERs such as phyto-derived CERs (PhytoCERs) can be delivered deep into the SC using novel topical formulations. This, however, requires investigating the rate and extent of skin permeation of CERs. In this study, an LC/APCI-MS method to detect and quantify PhytoCERs in different layers of the skin has been developed and validated. The method was used to investigate the skin permeation of PhytoCERs using Franz diffusion cells after applying an amphiphilic cream containing PhytoCERs to the surface of ex vivo human skin. As plant-specific CERs are not commercially available, well-characterized CERs isolated from oat (Avena abyssinica) were used as reference standards for the development and validation of the method. The method was linear over the range of 30–1050 ng/mL and sensitive with limit of detection and quantification of 10 and 30 ng/mL, respectively. The method was also selective, accurate, and precise with minimal matrix effect (with mean matrix factor around 100%). Even if more than 85% of oat CERs in the cream remained in the cream after the incubation periods of 30, 100, and 300 min, it was possible to quantify the small quantities of oat CERs distributed across the SC, epidermis, and dermis of the skin indicating the method’s sensitivity. Therefore, the method can be used to investigate the skin permeation of oat CERs from the various pharmaceutical and cosmeceutical products without any interference from the skin constituents such as the epidermal lipids. A2 - C1 - Bioorganic Chemistry ER - TY - JOUR ID - 829 TI - Identification of UDP glucosyltransferases from the aluminum-resistant tree Eucalyptus camaldulensis forming β-glucogallin, the precursor of hydrolyzable tannins JO - Phytochemistry PY - 2018 SP - 154-161 AU - Tahara, K. AU - Nishiguchi, M. AU - Frolov, A. AU - Mittasch, J. AU - Milkowski, C. AU - VL - 152 UR - DO - 10.1016/j.phytochem.2018.05.005 AB - In the highly aluminum-resistant tree Eucalyptus camaldulensis, hydrolyzable tannins are proposed to play a role in internal detoxification of aluminum, which is a major factor inhibiting plant growth on acid soils. To understand and modulate the molecular mechanisms of aluminum detoxification by hydrolyzable tannins, the biosynthetic genes need to be identified. In this study, we identified and characterized genes encoding UDP-glucose:gallate glucosyltransferase, which catalyzes the formation of 1-O-galloyl-β-d-glucose (β-glucogallin), the precursor of hydrolyzable tannins. By homology-based cloning, seven full-length candidate cDNAs were isolated from E. camaldulensis and expressed in Escherichia coli as recombinant N-terminal His-tagged proteins. Phylogenetic analysis classified four of these as UDP glycosyltransferase (UGT) 84A subfamily proteins (UGT84A25a, -b, UGT84A26a, -b) and the other three as UGT84J subfamily proteins (UGT84J3, -4, -5). In vitro enzyme assays showed that the UGT84A proteins catalyzed esterification of UDP–glucose and gallic acid to form 1-O-galloyl-β-d-glucose, whereas the UGT84J proteins were inactive. Further analyses with UGT84A25a and −26a indicated that they also formed 1-O-glucose esters of other structurally related hydroxybenzoic and hydroxycinnamic acids with a preference for hydroxybenzoic acids. The UGT84A genes were expressed in leaves, stems, and roots of E. camaldulensis, regardless of aluminum stress. Taken together, our results suggest that the UGT84A subfamily enzymes of E. camaldulensis are responsible for constitutive production of 1-O-galloyl-β-d-glucose, which is the first step of hydrolyzable tannin biosynthesis. A2 - C1 - Bioorganic Chemistry ER - TY - JOUR ID - 828 TI - The concerted amyloid-beta clearance of LRP1 and ABCB1/P-gp across the blood-brain barrier is linked by PICALM JO - Brain Behav. Immun. PY - 2018 SP - 21-33 AU - Storck, S. E. AU - Hartz, A. M. AU - Bernard, J. AU - Wolf, A. AU - Kachlmeier, A. AU - Mahringer, A. AU - Weggen, S. AU - Pahnke, J. AU - Pietrzik, C. U. AU - VL - 73 UR - DO - 10.1016/j.bbi.2018.07.017 AB - The accumulation of neurotoxic amyloid-beta (Aβ) in the brain is a characteristic hallmark of Alzheimer’s disease (AD). The blood-brain barrier (BBB) provides a large surface area and has been shown to be an important mediator for removal of brain Aβ. Both, the ABC transporter P-glycoprotein (ABCB1/P-gp) and the receptor low-density lipoprotein receptor-related protein 1 (LRP1) have been implicated to play crucial roles in Aβ efflux from brain. Here, with immunoprecipitation experiments, co-immunostainings and dual inhibition of ABCB1/P-gp and LRP1, we show that both proteins are functionally linked, mediating a concerted transcytosis of Aβ through endothelial cells. Late-onset AD risk factor Phosphatidylinositol binding clathrin assembly protein (PICALM) is associated with both ABCB1/P-gp and LRP1 representing a functional link and guiding both proteins through the brain endothelium. Together, our results give more mechanistic insight on Aβ transport across the BBB and show that the functional interplay of different clearance proteins is needed for the rapid removal of Aβ from the brain. A2 - C1 - Bioorganic Chemistry ER - TY - JOUR ID - 825 TI - Photochemical activity changes accompanying the embryogenesis of pea (Pisum sativum) with yellow and green cotyledons JO - Funct. Plant Biol. PY - 2018 SP - 228-235 AU - Smolikova, G. AU - Kreslavski, V. AU - Shiroglazova, O. AU - Bilova, T. AU - Sharova, E. AU - Frolov, A. AU - Medvedev, S. AU - VL - 45 UR - DO - 10.1071/FP16379 AB - The pea seeds are photosynthetically active until the end of the maturation phase, when the embryonic chlorophylls degrade. However, in some cultivars, the underlying mechanisms are compromised, and the mature seeds preserve green colour. The residual chlorophylls can enhance oxidative degradation of reserve biomolecules, and affect thereby the quality, shelf life and nutritive value of seeds. Despite this, the formation, degradation, and physical properties of the seed chlorophylls are still not completely characterised. So here we address the dynamics of seed photochemical activity in the yellow- and green-seeded pea cultivars by the pulse amplitude modulation (PAM) fluorometric analysis. The experiments revealed the maximal photochemical activity at the early- and mid-cotyledon stages. Thereby, the active centres of PSII were saturated at the light intensity of 15–20 µmol photons m–2 s–1. Despite of their shielding from the light by the pod wall and seed coat, photochemical reactions can be registered in the seeds with green embryo. Importantly, even at the low light intensities, the photochemical activity in the coats and cotyledons could be detected. The fast transients of the chlorophyll a fluorescence revealed a higher photochemical activity in the coat of yellow-seeded cultivars in comparison to those with the green-seeded ones. However, it declined rapidly in all seeds at the late cotyledon stage, and was accompanied with the decrease of the seed water content. Thus, the termination of photosynthetic activity in seeds is triggered by their dehydration. A2 - C1 - Bioorganic Chemistry ER - TY - JOUR ID - 955 TI - In Vitro Anticancer Evaluation of Platinum(II/IV) Complexes with Diisoamyl Ester of (S,S)-ethylenediamine-N,N’-di-2-propanoic Acid JO - Anti-Cancer Agents Med. Chem. PY - 2017 SP - 1136-1143 AU - Zmejkovski, B. B. AU - Pantelić, N. AU - Filipović, L. AU - Aranđelović, S. AU - Radulović, S. AU - Sabo, T. J. AU - Kaluđerović, G. N. AU - VL - 17 UR - DO - 10.2174/1871520616666161207155634 AB - Aims: Platinum(II) and platinum(IV) complexes [PtCln{(S,S)-(i-Am)2eddip}] (n = 2, 4: 1, 2, respectively; (S,S)-(i-Am)2eddip = O,O’-diisoamyl-(S,S)-ethylenediamine-N,N’-di-2-propanoate) were synthesized and characterized by elemental analysis, IR, 1H and 13C NMR spectroscopy and mass spectrometry.Method: Quantum chemical calculations were used to predict formed isomers of 1 and 2. Furthermore, reduction of 2 with ascorbic acid was followed by time-dependant 13C NMR spectroscopy in order to enable assignation of the formed isomers for complex 1. In vitro cytotoxic activity was determined for 1 and 2 on a panel of five human tumor cell lines derived from cervix adenocarcinoma (HeLa), alveolar basal adenocarcinoma (A549), breast adenocarcinoma (MDA-453), colorectal cancer (LS 174), erythromyeloblastoid leukemia (K562), as well as one non-malignant human lung fibroblast cell line (MRC-5), using MTT assay. Result: Both complexes exhibited high (2 against K562: IC50 = 5.4 μM), more active than cisplatin, to moderate activity (1). Both complexes caused considerable decrease of cell number in K562 cells in G1, S and G2 phases, concordantly increasing subpopulation in sub-G1 fraction. Morphological analysis of K562 cell death induced by platinum(II/IV) complexes indicate apoptosis. A2 - C1 - Bioorganic Chemistry ER - TY - JOUR ID - 935 TI - Expression of endogenous mouse APP modulates β-amyloid deposition in hAPP-transgenic mice JO - Acta Neuropathol. Commun. PY - 2017 SP - 49 AU - Steffen, J. AU - Krohn, M. AU - Schwitlick, C. AU - Brüning, T. AU - Paarmann, K. AU - Pietrzik, C. U. AU - Biverstål, H. AU - Jansone, B. AU - Langer, O. AU - Pahnke, J. AU - VL - 5 UR - DO - 10.1186/s40478-017-0448-2 AB - Amyloid-β (Aβ) deposition is one of the hallmarks of the amyloid hypothesis in Alzheimer’s disease (AD). Mouse models using APP-transgene overexpression to generate amyloid plaques have shown to model only certain parts of the disease. The extent to which the data from mice can be transferred to man remains controversial. Several studies have shown convincing treatment results in reducing Aβ and enhancing cognition in mice but failed totally in human. One model-dependent factor has so far been almost completely neglected: the endogenous expression of mouse APP and its effects on the transgenic models and the readout for therapeutic approaches.Here, we report that hAPP-transgenic models of amyloidosis devoid of endogenous mouse APP expression (mAPP-knockout / mAPPko) show increased amounts and higher speed of Aβ deposition than controls with mAPP. The number of senile plaques and the level of aggregated hAβ were elevated in mAPPko mice, while the deposition in cortical blood vessels was delayed, indicating an alteration in the general aggregation propensity of hAβ together with endogenous mAβ. Furthermore, the cellular response to Aβ deposition was modulated: mAPPko mice developed a pronounced and age-dependent astrogliosis, while microglial association to amyloid plaques was diminished. The expression of human and murine aggregation-prone proteins with differing amino acid sequences within the same mouse model might not only alter the extent of deposition but also modulate the route of pathogenesis, and thus, decisively influence the study outcome, especially in translational research. A2 - C1 - Bioorganic Chemistry ER - TY - JOUR ID - 933 TI - Quantification of prospective type 2 diabetes mellitus biomarkers by stable isotope dilution with bi-labeled standard glycated peptides JO - Anal. Methods PY - 2017 SP - 409-418 AU - Soboleva, A. AU - Modzel, M. AU - Didio, A. AU - Płóciennik, H. AU - Kijewska, M. AU - Grischina, T. AU - Karonova, T. AU - Bilova, T. AU - Stefanov, V. AU - Stefanowicz, P. AU - Frolov, A. AU - VL - 9 UR - DO - 10.1039/C6AY02483A AB - Type 2 diabetes mellitus (T2DM) is a complex group of disorders, characterized by hyperglycemia, insulin resistance and insulin deficiency. In human blood, hyperglycemia ultimately results in the enhancement of glycation – a posttranslational modification formed by the interaction of protein amino groups with glucose. The resulting fructosamines (Amadori compounds) readily undergo further degradation resulting in advanced glycation end products (AGEs), known to be pro-inflammatory in humans. These compounds are highly heterogeneous and characteristic of advanced stages of the disease, whereas fructosamines are recognized markers of early diabetes stages (HbA1C, glycated albumin). Recently, individual plasma protein glycation sites were proposed as promising T2DM biomarkers sensitive to short-term fluctuations of plasma glucose. However, corresponding absolute quantification strategies, applicable in regular clinical practice, are still not established. Therefore, here we propose a new analytical approach aiming at reproducible and precise quantification of multiple glycated peptides in human plasma tryptic digests. Thereby, the standard peptides comprised a 13C,15N-labeled lysyl residue, a dabsyl moiety for determination of standard amounts, and a cleavable linker. Known amounts of these peptides were spiked to plasma samples prior to tryptic digestion, quantification relying on stable isotope dilution. The method was demonstrated to be applicable for quantification of individual glycated sites in T2DM patients and non-diabetic controls. A2 - C1 - Bioorganic Chemistry ER - TY - JOUR ID - 932 TI - Probing Protein Glycation by Chromatography and Mass Spectrometry: Analysis of Glycation Adducts JO - Int. J. Mol. Sci. PY - 2017 SP - 2557 AU - Soboleva, A. AU - Vikhnina, M. AU - Grishina, T. AU - Frolov, A. AU - VL - 18 UR - DO - 10.3390/ijms18122557 AB - Glycation is a non-enzymatic post-translational modification of proteins, formed by the reaction of reducing sugars and α-dicarbonyl products of their degradation with amino and guanidino groups of proteins. Resulted early glycation products are readily involved in further transformation, yielding a heterogeneous group of advanced glycation end products (AGEs). Their formation is associated with ageing, metabolic diseases, and thermal processing of foods. Therefore, individual glycation adducts are often considered as the markers of related pathologies and food quality. In this context, their quantification in biological and food matrices is required for diagnostics and establishment of food preparation technologies. For this, exhaustive protein hydrolysis with subsequent amino acid analysis is the strategy of choice. Thereby, multi-step enzymatic digestion procedures ensure good recoveries for the most of AGEs, whereas tandem mass spectrometry (MS/MS) in the multiple reaction monitoring (MRM) mode with stable isotope dilution or standard addition represents “a gold standard” for their quantification. Although the spectrum of quantitatively assessed AGE structures is continuously increases, application of untargeted profiling techniques for identification of new products is desired, especially for in vivo characterization of anti-glycative systems. Thereby, due to a high glycative potential of plant metabolites, more attention needs to be paid on plant-derived AGEs. A2 - C1 - Bioorganic Chemistry ER - TY - JOUR ID - 931 TI - Maillard Proteomics: Opening New Pages JO - Int. J. Mol. Sci. PY - 2017 SP - 2677 AU - Soboleva, A. AU - Schmidt, R. AU - Vikhnina, M. AU - Grishina, T. AU - Frolov, A. AU - VL - 18 UR - DO - 10.3390/ijms18122677 AB - Protein glycation is a ubiquitous non-enzymatic post-translational modification, formed by reaction of protein amino and guanidino groups with carbonyl compounds, presumably reducing sugars and α-dicarbonyls. Resulting advanced glycation end products (AGEs) represent a highly heterogeneous group of compounds, deleterious in mammals due to their pro-inflammatory effect, and impact in pathogenesis of diabetes mellitus, Alzheimer’s disease and ageing. The body of information on the mechanisms and pathways of AGE formation, acquired during the last decades, clearly indicates a certain site-specificity of glycation. It makes characterization of individual glycation sites a critical pre-requisite for understanding in vivo mechanisms of AGE formation and developing adequate nutritional and therapeutic approaches to reduce it in humans. In this context, proteomics is the methodology of choice to address site-specific molecular changes related to protein glycation. Therefore, here we summarize the methods of Maillard proteomics, specifically focusing on the techniques providing comprehensive structural and quantitative characterization of glycated proteome. Further, we address the novel break-through areas, recently established in the field of Maillard research, i.e., in vitro models based on synthetic peptides, site-based diagnostics of metabolism-related diseases (e.g., diabetes mellitus), proteomics of anti-glycative defense, and dynamics of plant glycated proteome during ageing and response to environmental stress. A2 - C1 - Bioorganic Chemistry ER - TY - JOUR ID - 930 TI - Genetic and Hormonal Regulation of Chlorophyll Degradation during Maturation of Seeds with Green Embryos JO - Int. J. Mol. Sci. PY - 2017 SP - 1993 AU - Smolikova, G. AU - Dolgikh, E. AU - Vikhnina, M. AU - Frolov, A. AU - Medvedev, S. AU - VL - 18 UR - DO - 10.3390/ijms18091993 AB - The embryos of some angiosperms (usually referred to as chloroembryos) contain chlorophylls during the whole period of embryogenesis. Developing embryos have photochemically active chloroplasts and are able to produce assimilates, further converted in reserve biopolymers, whereas at the late steps of embryogenesis, seeds undergo dehydration, degradation of chlorophylls, transformation of chloroplast in storage plastids, and enter the dormancy period. However, in some seeds, the process of chlorophyll degradation remains incomplete. These residual chlorophylls compromise the quality of seed material in terms of viability, nutritional value, and shelf life, and represent a serious challenge for breeders and farmers. The mechanisms of chlorophyll degradation during seed maturation are still not completely understood, and only during the recent decades the main pathways and corresponding enzymes could be characterized. Among the identified players, the enzymes of pheophorbide a oxygenase pathway and the proteins encoded by STAY GREEN (SGR) genes are the principle ones. On the biochemical level, abscisic acid (ABA) is the main regulator of seed chlorophyll degradation, mediating activity of corresponding catabolic enzymes on the transcriptional level. In general, a deep insight in the mechanisms of chlorophyll degradation is required to develop the approaches for production of chlorophyll-free high quality seeds. A2 - C1 - Bioorganic Chemistry ER - TY - JOUR ID - 929 TI - Improved method for cannula fixation for long-term intracerebral brain infusion JO - J. Neurosci. Meth. PY - 2017 SP - 145-150 AU - Sike, ?. AU - Wengenroth, J. AU - Upīte, J. AU - Brüning, T. AU - Eiriz, I. AU - Sántha, P. AU - Biverstål, H. AU - Jansone, B. AU - Haugen, H. J. AU - Krohn, M. AU - Pahnke, J. AU - VL - 290 UR - DO - 10.1016/j.jneumeth.2017.07.026 AB - BackgroundImplanted osmotic minipumps are commonly used for long-term, brain-targeted delivery of a wide range of experimental agents by being connected to a catheter and a cannula. During the stereotactical surgery procedure, the cannula has to be placed correctly in the x-y directions and also with respect to the injection point in the z-direction (deepness). However, the flat fixation base of available cannula holders doesn’t allow an easy, secure fixation onto the curve-shaped skull.New methodWe have developed a modified method for a better fixation of the cannula holder by using an easy-to-produce, skull-shaped silicone spacer as fixation adapter.ResultsWe describe the application and its fast and reliable production in the lab.Comparison with existing method(s)Superglue or cement is currently being used as the method of choice. However, the curve-shaped skull surface does not fit well with the flat and rigid cannula adapter which leads to fixation problems over time causing wide infusion channels and often also to leakage problems from intracerebrally applied agents towards the surface meninges. As another consequence of the inappropriate fixation, the cannula may loosen from the skull before the end of the experiment or it causes damage to the brain tissue, harming the animals with leading to a failure of the whole experiment.ConclusionsThe easy-to-produce spacer facilitates the crucial step of long-term, stereotactic brain infusion experiments with intracerebral catheters in a highly secure and reproducible way. A2 - C1 - Bioorganic Chemistry ER - TY - JOUR ID - 920 TI - Altered protein expression pattern in colon tissue of mice upon supplementation with distinct selenium compounds JO - Proteomics PY - 2017 SP - 1600486 AU - Rahn, J. AU - Lennicke, C. AU - Kipp, A. P. AU - Müller, A. S. AU - Wessjohann, L. A. AU - Lichtenfels, R. AU - Seliger, B. AU - VL - 17 UR - DO - 10.1002/pmic.201600486 AB - The essential trace element selenium (Se) is controversially discussed concerning its role in health and disease. Its various physiological functions are largely mediated by Se incorporation in the catalytic center of selenoproteins. In order to gain insights into the impact of Se deficiency and of supplementation with different Se compounds (selenite, selenate, selenomethionine) at defined concentrations (recommended, 150 μg/kg diet; excessive, 750 μg/kg diet) in murine colon tissues, a 20‐week feeding experiment was performed followed by analysis of the protein expression pattern of colon tissue specimens by 2D‐DIGE and MALDI‐TOF MS. Using this approach, 24 protein spots were identified to be significantly regulated by the different Se compounds. These included the antioxidant enzyme peroxiredoxin‐5 (PRDX5), proteins with binding capabilities, such as cofilin‐1 (COF1), calmodulin, and annexin A2 (ANXA2), and proteins involved in catalytic processes, such as 6‐phosphogluconate dehydrogenase (6PGD). Furthermore, the Se compounds demonstrated a differential impact on the expression of the identified proteins. Selected target structures were validated by qPCR and Western blot which mainly confirmed the proteomic profiling data. Thus, novel Se‐regulated proteins in colon tissues have been identified, which expand our understanding of the physiologic role of Se in colon tissue. A2 - C1 - Bioorganic Chemistry ER - TY - JOUR ID - 917 TI - Antiproliferative Activity of Gold(III) Complexes with Esters of Cyclohexyl-Functionalized Ethylenediamine-N,N’-Diacetate JO - Serb. J. Exp. Clin. Res. PY - 2017 SP - 289-294 AU - Pantelić, N. AU - Stanojković, T. P. AU - Zmejkovski, B. B. AU - Kaluđerović, G. N. AU - Sabo, T. J. AU - VL - 18 UR - DO - 10.1515/sjecr-2017-0067 AB - Six gold(III) complexes with esters of cyclohexyl-functionalized ethylenediamine-N,N’-diacetate, general formula [AuCl2{(S,S)-R2eddch}]PF6, [(S,S)-eddch = (S,S)-ethylenediamine-N,N’-di-2-(3-cyclohexyl)propanoate, R = Me, Et, n-Pr, n-Bu, i-Bu, i-Am, 1–6, respectively], were tested against cancer cell lines such as human melanoma Fem-x, human colon carcinoma LS174T and non-small cell lung carcinoma A549 as well as a non-cancerous human embryonic lung fibroblasts MRC-5 using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay with the aim of assessing in vitro antitumoral activity and selectivity. All investigated complexes showed lower cytotoxicity and better or similar selectivity in comparison to cisplatin, used as reference compound. Complex [AuCl2{(S,S)-(i-Am)2eddch}]PF6 (6) demonstrated the highest activity against Fem-x (IC50 = 14.98 ± 0.34 μM). Additionally, the same complex expressed 4.5 times higher selectivity than cisplatin. A2 - C1 - Bioorganic Chemistry ER - TY - JOUR ID - 916 TI - In vitro antitumor activity, metal uptake and reactivity with ascorbic acid and BSA of some gold(III) complexes with N,N′-ethylenediamine bidentate ester ligands JO - J. Inorg. Biochem. PY - 2017 SP - 55-66 AU - Pantelić, N. AU - Zmejkovski, B. B. AU - Kolundžija, B. AU - Crnogorac, M. ?. AU - Vujić, J. M. AU - Dojčinović, B. AU - Trifunović, S. R. AU - Stanojković, T. P. AU - Sabo, T. J. AU - Kaluđerović, G. N. AU - VL - 172 UR - DO - 10.1016/j.jinorgbio.2017.04.001 AB - Four novel gold(III) complexes of general formulae [AuCl2{(S,S)-R2eddl}]PF6 (R2eddl = O,O′-dialkyl-(S,S)-ethylenediamine-N,N′-di-2-(4-methyl)pentanoate, R = n-Pr, n-Bu, n-Pe, i-Bu; 1–4, respectively), were synthesized and characterized by elemental analysis, UV/Vis, IR, and NMR spectroscopy, as well as high resolution mass spectrometry. Density functional theory calculations pointed out that (R,R)-N,N′-configuration diastereoisomers were energetically the most favorable. Duo to high cytotoxic activity complex 3 was chosen for stability study in DMSO, no decomposition occurs within 24 h, and for the reaction with ascorbic acid in which was reduced immediately. Additionally, 3 interacts with bovine serum albumin (BSA) as proven by UV/Vis spectroscopy. In vitro antitumor activity was determined against human cervix adenocarcinoma (HeLa), human myelogenous leukemia (K562), and human melanoma (Fem-x) cancer cell lines, as well as against non-cancerous human embryonic lung fibroblast cells MRC-5. The highest activity was observed against K562 cells (IC50: 5.04–6.51 μM). Selectivity indices showed that these complexes are less toxic than cisplatin. 3 had a similar viability kinetics on HeLa cells as cisplatin. Drug accumulation studies in HeLa cells showed that the total gold uptake increased much faster than that of cisplatin pointing out that 3 more efficiently enters the cells than cisplatin. Furthermore, morphological and cell cycle analysis reveal that gold(III) complexes induced apoptosis in time- and dose-dependent manner. A2 - C1 - Bioorganic Chemistry ER - TY - JOUR ID - 854 TI - Hierarchical cluster analysis and chemical characterisation of Myrtus communis L. essential oil from Yemen region and its antimicrobial, antioxidant and anti-colorectal adenocarcinoma properties JO - Nat. Prod. Res. PY - 2017 SP - 2158-2163 AU - Anwar, S. AU - Crouch, R. A. AU - Awadh Ali, N. A. AU - Al-Fatimi, M. A. AU - Setzer, W. N. AU - Wessjohann, L. AU - VL - 31 UR - DO - 10.1080/14786419.2016.1277346 AB - The hydrodistilled essential oil obtained from the dried leaves of Myrtus communis, collected in Yemen, was analysed by GC–MS. Forty-one compounds were identified, representing 96.3% of the total oil. The major constituents of essential oil were oxygenated monoterpenoids (87.1%), linalool (29.1%), 1,8-cineole (18.4%), α-terpineol (10.8%), geraniol (7.3%) and linalyl acetate (7.4%). The essential oil was assessed for its antimicrobial activity using a disc diffusion assay and resulted in moderate to potent antibacterial and antifungal activities targeting mainly Bacillus subtilis, Staphylococcus aureus and Candida albicans. The oil moderately reduced the diphenylpicrylhydrazyl radical (IC50 = 4.2 μL/mL or 4.1 mg/mL). In vitro cytotoxicity evaluation against HT29 (human colonic adenocarcinoma cells) showed that the essential oil exhibited a moderate antitumor effect with IC50 of 110 ± 4 μg/mL. Hierarchical cluster analysis of M. communis has been carried out based on the chemical compositions of 99 samples reported in the literature, including Yemeni sample. A2 - C1 - Bioorganic Chemistry ER - TY - JOUR ID - 852 TI - Antimicrobial, Antioxidant, and Cytotoxic Activities of Ocimum forskolei and Teucrium yemense (Lamiaceae) Essential Oils JO - Medicines PY - 2017 SP - 17 AU - Ali, N. A. A. AU - Chhetri, B. K. AU - Dosoky, N. S. AU - Shari, K. AU - Al-Fahad, A. J. A. AU - Wessjohann, L. AU - Setzer, W. N. AU - VL - 4 UR - DO - 10.3390/medicines4020017 AB - Background:Ocimum forskolei and Teucrium yemense (Lamiaceae) are used in traditional medicine in Yemen. Methods: The chemical composition, antimicrobial, antioxidant and cytotoxic activities of the essential oils isolated from the leaves of Ocimum forskolei Benth. (EOOF) and two different populations of Teucrium yemense Deflers., one collected from Dhamar province (EOTY-d), and another collected from Taiz (EOTY-t) were investigated. The antimicrobial activities of the oils were evaluated against several microorganisms with the disc diffusion test or the broth microdilution test. The essential oils were screened for in-vitro cytotoxic activity against human tumor cells. EOOF and EOTY-d were screened for free-radical-inhibitory activity using the DPPH radical scavenging assay. Results: Sixty-four compounds were identified in (EOOF) representing 100% of the oil content with endo-fenchol (31.1%), fenchone (12.2%), τ-cadinol (12.2%), and methyl (E)-cinnamate (5.1%) as the major compounds. In EOTY-d, 67 compounds were identified, which made up 91% of the total oil. The most abundant constituents were (E)-caryophyllene (11.2%), α-humulene (4.0.%), γ-selinene (5.5%), 7-epi-α-selinene (20.1%), and caryophyllene oxide (20.1%), while the major compounds in EOTY-t were α-pinene (6.6%), (E)-caryophyllene (19.1%) α-humulene (6.4%), δ-cadinene (6.5%), caryophyllene oxide (4.3%), α-cadinol (9.5%), and shyobunol (4.6%). The most sensitive microorganisms for EOOF were B. subtilis, S. aureus, and C. albicans with inhibition zones of 34, 16, and 24 mm and MIC values of, 4.3 mg/mL, 4.3 mg/mL, and 8.6 mg/mL, respectively. EOTY-t showed antimicrobial activity against S. aureus, B. cereus, A. niger, and B. cinerea with MIC values of 0.156, 0.156, 0.313 and 0.313 mg/mL, respectively. Neither essential oil showed remarkable radical inhibition (IC50 = 31.55 and 31.41 μL/mL). EOTY-d was active against HT-29 human colorectal adenocarcinoma cell lines with IC50 = 43.7 μg/mL. Consistent with this, EOTY-t was active against both MCF-7 and MDA-MB-231 human breast adenocarcinoma cells. Conclusions: The antimicrobial activity of Ocimum forskolei essential oil against B. subtilis and C. albicans is consistent with its traditional use in Yemeni traditional medicine to treat skin infections. Both O. forskolei and T. yemense show wide variations in their respective essential oil compositions; there remains a need to investigate both species botanically, genetically, and phytochemically more comprehensively. A2 - C1 - Bioorganic Chemistry ER - TY - JOUR ID - 851 TI - Structural studies of amyloid-β peptides: Unlocking the mechanism of aggregation and the associated toxicity JO - Biochimie PY - 2017 SP - 176-192 AU - Aleksis, R. AU - Oleskovs, F. AU - Jaudzems, K. AU - Pahnke, J. AU - Biverstål, H. AU - VL - 140 UR - DO - 10.1016/j.biochi.2017.07.011 AB - Alzheimer's disease (AD) is one of the most prevalent neurodegenerative diseases worldwide. Formation of amyloid plaques consisting of amyloid-β peptides (Aβ) is one of the hallmarks of AD. Several lines of evidence have shown a correlation between the Aβ aggregation and the disease development. Extensive research has been conducted with the aim to reveal the structures of the neurotoxic Aβ aggregates. However, the exact structure of pathological aggregates and mechanism of the disease still remains elusive due to complexity of the occurring processes and instability of various disease-relevant Aβ species. In this article we review up-to-date structural knowledge about amyloid-β peptides, focusing on data acquired using solution and solid state NMR techniques. Furthermore, we discuss implications from these structural studies on the mechanisms of aggregation and neurotoxicity. A2 - C1 - Bioorganic Chemistry ER - TY - JOUR ID - 876 TI - Early responses of mature Arabidopsis thaliana plants to reduced water potential in the agar-based polyethylene glycol infusion drought model JO - J. Plant Physiol. PY - 2017 SP - 70-83 AU - Frolov, A. AU - Bilova, T. AU - Paudel, G. AU - Berger, R. AU - Balcke, G. U. AU - Birkemeyer, C. AU - Wessjohann, L. A. AU - VL - 208 UR - DO - 10.1016/j.jplph.2016.09.013 AB - Drought is one of the most important environmental stressors resulting in increasing losses of crop plant productivity all over the world. Therefore, development of new approaches to increase the stress tolerance of crop plants is strongly desired. This requires precise and adequate modeling of drought stress. As this type of stress manifests itself as a steady decrease in the substrate water potential (ψw), agar plates infused with polyethylene glycol (PEG) are the perfect experimental tool: they are easy in preparation and provide a constantly reduced ψw, which is not possible in soil models. However, currently, this model is applicable only to seedlings and cannot be used for evaluation of stress responses in mature plants, which are obviously the most appropriate objects for drought tolerance research. To overcome this limitation, here we introduce a PEG-based agar infusion model suitable for 6–8-week-old A. thaliana plants, and characterize, to the best of our knowledge for the first time, the early drought stress responses of adult plants grown on PEG-infused agar. We describe essential alterations in the primary metabolome (sugars and related compounds, amino acids and polyamines) accompanied by qualitative and quantitative changes in protein patterns: up to 87 unique stress-related proteins were annotated under drought stress conditions, whereas further 84 proteins showed a change in abundance. The obtained proteome patterns differed slightly from those reported for seedlings and soil-based models. A2 - C1 - Cell and Metabolic Biology; Bioorganic Chemistry ER - TY - JOUR ID - 858 TI - Global proteomic analysis of advanced glycation end products in the Arabidopsis proteome provides evidence for age-related glycation hot spots JO - J. Biol. Chem. PY - 2017 SP - 15758-15776 AU - Bilova, T. AU - Paudel, G. AU - Shilyaev, N. AU - Schmidt, R. AU - Brauch, D. AU - Tarakhovskaya, E. AU - Milrud, S. AU - Smolikova, G. AU - Tissier, A. AU - Vogt, T. AU - Sinz, A. AU - Brandt, W. AU - Birkemeyer, C. AU - Wessjohann, L. A. AU - Frolov, A. AU - VL - 292 UR - DO - 10.1074/jbc.M117.794537 AB - Glycation is a post-translational modification resulting from the interaction of protein amino and guanidino groups with carbonyl compounds. Initially, amino groups react with reducing carbohydrates, yielding Amadori and Heyns compounds. Their further degradation results in formation of advanced glycation end products (AGEs), also originating from α-dicarbonyl products of monosaccharide autoxidation and primary metabolism. In mammals, AGEs are continuously formed during the life of the organism, accumulate in tissues, are well-known markers of aging, and impact age-related tissue stiffening and atherosclerotic changes. However, the role of AGEs in age-related molecular alterations in plants is still unknown. To fill this gap, we present here a comprehensive study of the age-related changes in the Arabidopsis thaliana glycated proteome, including the proteins affected and specific glycation sites therein. We also consider the qualitative and quantitative changes in glycation patterns in terms of the general metabolic background, pathways of AGE formation, and the status of plant anti-oxidative/anti-glycative defense. Although the patterns of glycated proteins were only minimally influenced by plant age, the abundance of 96 AGE sites in 71 proteins was significantly affected in an age-dependent manner and clearly indicated the existence of age-related glycation hot spots in the plant proteome. Homology modeling revealed glutamyl and aspartyl residues in close proximity (less than 5 Å) to these sites in three aging-specific and eight differentially glycated proteins, four of which were modified in catalytic domains. Thus, the sites of glycation hot spots might be defined by protein structure that indicates, at least partly, site-specific character of glycation. A2 - C1 - Cell and Metabolic Biology; Bioorganic Chemistry ER - TY - JOUR ID - 903 TI - The choroid plexus in health and in disease: dialogues into and out of the brain JO - Neurobiol. Dis. PY - 2017 SP - 32-40 AU - Marques, F. AU - Sousa, J. C. AU - Brito, M. A. AU - Pahnke, J. AU - Santos, C. AU - Correia-Neves, M. AU - Palha, J. A. AU - VL - 107 UR - DO - 10.1016/j.nbd.2016.08.011 AB - This article brings the choroid plexus into the context of health and disease. It is remarkable that the choroid plexus, composed by a monolayer of epithelial cells that lie in a highly vascularized stroma, floating within the brain ventricles, gets so little attention in major physiology and medicine text books and in the scientific literature in general. Consider that it is responsible for producing most of the about 150 mL of cerebrospinal fluid that fills the brain ventricles and the subarachnoid space and surrounds the spinal cord in the adult human central nervous system, which is renewed approximately 2–3 times daily. As such, its activity influences brain metabolism and function, which will be addressed. Reflect that it contains an impressive number of receptors and transporters, both in the apical and basolateral sides of the epithelial cells, and as such is a key structure for the communication between the brain and the periphery. This will be highlighted in the context of neonatal jaundice, multiple sclerosis and Alzheimer's disease. Realize that the capillaries that irrigate the choroid plexus stroma do not possess tight junctions and that the blood flow to the choroid plexus is five times higher than that in the brain parenchyma, allowing for a rapid sensing system and delivery of molecules such as nutrients and metals as will be revised. Recognize that certain drugs reach the brain parenchyma solely through the choroid plexus epithelia, which has potential to be manipulated in diseases such as neonatal jaundice and Alzheimer's disease as will be discussed. Without further notice, it must be now clear that understanding the choroid plexus is necessary for comprehending the brain and how the brain is modulated and modulates all other systems, in health and in disease. This review article intends to address current knowledge on the choroid plexus, and to motivate the scientific community to consider it when studying normal brain physiology and diseases of the central nervous system. It will guide the reader through several aspects of the choroid plexus in normal physiology, in diseases characteristic of various periods of life (newborns-kernicterus, young adults-multiple sclerosis and the elder-Alzheimer's disease), and how sex-differences may relate to disease susceptibility. A2 - C1 - Bioorganic Chemistry ER - TY - JOUR ID - 899 TI - Modulation of MHC class I surface expression in B16F10 melanoma cells by methylseleninic acid JO - OncoImmunology PY - 2017 SP - e1259049 AU - Lennicke, C. AU - Rahn, J. AU - Bukur, J. AU - Hochgräfe, F. AU - Wessjohann, L. A. AU - Lichtenfels, R. AU - Seliger, B. AU - VL - 6 UR - DO - 10.1080/2162402X.2016.1259049 AB - The essential trace element selenium (Se) might play a role in cancer prevention as well as for cancer therapy. Its metabolite methylselenol is able to kill cells through distinct mechanisms including induction of reactive oxygen species, DNA damage and apoptosis. Since methylselenol affects innate immune responses by modulating the expression of NKG2D ligands, the aim of this study was to determine whether the methylselenol generating compound methylseleninic acid (MSA) influences the expression of the MHC class I surface antigens and growth properties thereby reverting immune escape.Treatment of B16F10 melanoma cells expressing low basal MHC class I surface antigens with dimethyldiselenide (DMDSe) and MSA, but not with selenomethionine and selenite resulted in a dose-dependent upregulation of MHC class I cell surface antigens. This was due to a transcriptional upregulation of some major components of the antigen processing machinery (APM) and the interferon (IFN) signaling pathway and accompanied by a reduced migration of B16F10 melanoma cells in the presence of MSA. Comparative “ome”-based profilings of untreated and MSA-treated melanoma cells linked the anti-oxidative response system with MHC class I antigen processing. Since MSA treatment enhanced MHC class I surface expression also on different human tumors cell lines, MSA might affect the malignant phenotype of various tumor cells by restoring MHC class I APM component expression due to an altered redox status and by partially mimicking IFN-gamma signaling thereby providing a novel mechanism for the chemotherapeutic potential of methylselenol generating Se compounds. A2 - C1 - Bioorganic Chemistry ER - TY - JOUR ID - 898 TI - Individual effects of different selenocompounds on the hepatic proteome and energy metabolism of mice JO - BBA-Gen. Subjects PY - 2017 SP - 3323-3334 AU - Lennicke, C. AU - Rahn, J. AU - Kipp, A. P. AU - Dojčinović, B. P. AU - Müller, A. S. AU - Wessjohann, L. A. AU - Lichtenfels, R. AU - Seliger, B. AU - VL - 1861 UR - DO - 10.1016/j.bbagen.2016.08.015 AB - BackgroundSelenium (Se) exerts its biological activity largely via selenoproteins, which are key enzymes for maintaining the cellular redox homeostasis. However, besides these beneficial effects there is also evidence that an oversupply of Se might increase the risk towards developing metabolic disorders. To address this in more detail, we directly compared effects of feeding distinct Se compounds and concentrations on hepatic metabolism and expression profiles of mice.MethodsMale C57BL6/J mice received either a selenium-deficient diet or diets enriched with adequate or high doses of selenite, selenate or selenomethionine for 20 weeks. Subsequently, metabolic parameters, enzymatic activities and expression levels of hepatic selenoproteins, Nrf2 targets, and additional redox-sensitive proteins were analyzed. Furthermore, 2D-DIGE-based proteomic profiling revealed Se compound-specific differentially expressed proteins.ResultsWhereas heterogeneous effects between high concentrations of the Se compounds were observed with regard to body weight and metabolic activities, selenoproteins were only marginally increased by high Se concentrations in comparison to the respective adequate feeding. In particular the high-SeMet group showed a unique response compromising higher hepatic Se levels in comparison to all other groups. Accordingly, hepatic glutathione (GSH) levels, glutathione S-transferase (GST) activity, and GSTpi1 expression were comparably high in the high-SeMet and Se-deficient group, indicating that compound-specific effects of high doses appear to be independent of selenoproteins.ConclusionsNot only the nature, but also the concentration of Se compounds differentially affect biological processes.General significanceThus, it is important to consider Se compound-specific effects when supplementing with selenium. A2 - C1 - Bioorganic Chemistry ER - TY - JOUR ID - 890 TI - (18-Crown-6)potassium(I) Trichlorido[28-acetyl-3-(tris-(hydroxylmethyl)amino-ethane)betulinic ester-κN]platinum(II): Synthesis and In Vitro Antitumor Activity JO - Inorganics PY - 2017 SP - 56 AU - Kaluđerović, G. N. AU - Bulatović, M. AU - Krajnović, T. AU - Paschke, R. AU - Zmejkovski, B. B. AU - Maksimović-Ivanić, D. AU - Mijatović, S. AU - VL - 5 UR - DO - 10.3390/inorganics5030056 AB - Synthesis of platinum(II) conjugate with acetylated betulinic acid tris(hydroxymethyl)aminomethane ester (BATRIS) is presented (BATRISPt). HR-ESI-MS and multinuclear NMR spectroscopy, as well as elemental analysis were used for characterization of BATRISPt. Cytotoxicity (3-(4,5-dimethythiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT), crystal violet (CV), and sulforhodamine B (SRB) assays) of BA, BATRIS, BATRISPt, and cisplatin were assessed on seven different tumor cell lines: melanoma B16, colon HCT116 and DLD-1, adenocarcinoma HeLa, breast MCF-7, and anaplastic thyroid tumor 8505C and SW1736; as well as normal MRC-5 fibroblasts. Furthermore, the effect of the mentioned compounds on the apoptosis (Annexin V/PI assay) and autophagy induction (acridine orange (AO) assay) as well as caspase 3, 8, and 9 activation were investigated on the selected B16 melanoma cell line. BATRISPt showed lower activity than BA, BATRIS, or cisplatin. All tested compounds triggered apoptosis in B16 cells. Induction of autophagy was observed in B16 cells exposed only to BATRIS. On the other hand, new conjugate activates caspases 8 and 9 in B16 cells with higher impact than BATRIS or cisplatin alone. A2 - C1 - Bioorganic Chemistry ER - TY - JOUR ID - 889 TI - Mesoporous silica nanoparticles SBA-15 loaded with emodin upregulate the antioxidative defense of Euproctis chrysorrhoea (L.) larvae JO - Turk. J. Biol. PY - 2017 SP - 935-942 AU - Janković-Tomanić, M. AU - Todorović, D. AU - Stanivuković, Z. AU - Perić Mataruga, V. AU - Wessjohann, L. A. AU - Kaluđerović, G. N. AU - VL - 41 UR - DO - 10.3906/biy-1705-76 AB - The study presented here aims to elucidate the effects of emodin (EO = 1,3,8-trihydroxy-6-methylanthraquinone) in its freeform and when loaded into a mesoporous silica nanocarrier SBA-15 (→ SBA-15|EO) on the activities of the main antioxidative enzymes,superoxide dismutase, catalase, glutathione S-transferase, and glutathione reductase, in larvae of a polyphagous insect pest, the browntailmoth Euproctis chrysorrhoea (L.). The results show that only SBA-15|EO upregulates the activities of the tested antioxidative enzymes.These results point to significant differences in the effectiveness of the compound in the free versus the loaded form. A2 - C1 - Bioorganic Chemistry ER - TY - JOUR ID - 885 TI - Anionic chlorido(triphenyl)tin(IV) bearing N-phthaloylglycinato or 1,2,4-benzenetricarboxylato 1,2-anhydride ligands: potential cytotoxic and apoptosis-inducing agents against several types of cancer JO - Chem. Biol. Drug Des. PY - 2017 SP - 628-633 AU - Hübner, D. AU - Kaluđerović, M. R. AU - Gómez-Ruiz, S. AU - Kaluđerović, G. N. AU - VL - 89 UR - DO - 10.1111/cbdd.12885 AB - Two ionic triphenyltin(IV) chloride carboxylate compounds of the formula [NHEt3][Ph3SnCl(L)] [LH = N‐phthaloylglycine (P‐GlyH), 1; 1,2,4‐benzenetricarboxylic 1,2‐anhydride (BTCH), 2] were tested for the in vitro activity against 518A2 (melanoma), FaDu (head and neck carcinoma), HT‐29 (colon cancer), MCF‐7 (breast carcinoma), and SW1736 (thyroid cancer) cell lines. The ammonium salts of the carboxylic acids are found to be not active, while anionic [Ph3SnCl(L)]− exhibited high cytotoxicity in nM range, both higher activity and selectivity than cisplatin. Compounds 1 and 2 are inducing apoptosis, which was proved with the morphological and biochemical features such as membrane blebbing, translocation of phosphatidylserine, and DNA fragmentation. Thus, accumulation of cells in sub‐G1 phase is observed. Both anionic organotin(IV) compounds showed potent cytotoxic and apoptotic properties against five cancer cell lines of various histogenetic origin. A2 - C1 - Bioorganic Chemistry ER - TY - CHAP ID - 41 TI - Computational Studies and Biosynthesis of Natural Products with Promising Anticancer Properties T2 - Natural Products and Cancer Drug Discovery PB - PY - 2017 SP - 257-285 AU - Moumbock, A. F. A. AU - Simoben, C. V. AU - Wessjohann, L. AU - Sippl, W. AU - Günther, S. AU - Ntie‐Kang, F. AU - VL - UR - SN - 978-953-51-3314-8 DO - 10.5772/67650 AB - We present an overview of computational approaches for the prediction of metabolic pathways by which plants biosynthesise compounds, with a focus on selected very promising anticancer secondary metabolites from floral sources. We also provide an overview of databases for the retrieval of useful genomic data, discussing the strengths and limitations of selected prediction software and the main computational tools (and methods), which could be employed for the investigation of the uncharted routes towards the biosynthesis of some of the identified anticancer metabolites from plant sources, eventually using specific examples to address some knowledge gaps when using these approaches. A2 - Badria, F. A., ed. C1 - Bioorganic Chemistry ER - TY - JOUR ID - 1025 TI - Synthesis, Characterization, and Cytotoxicity of a Novel Gold(III) Complex with O,O′-Diethyl Ester of Ethylenediamine-N,N′-Di-2-(4-Methyl)Pentanoic Acid JO - Metals PY - 2016 SP - 226 AU - Pantelić, N. AU - Zmejkovski, B. B. AU - Marković, D. D. AU - Vujić, J. M. AU - Stanojković, T. P. AU - Sabo, T. J. AU - Kaluđerović, G. N. AU - VL - 6 UR - DO - 10.3390/met6090226 AB - A novel gold(III) complex, [AuCl2{(S,S)-Et2eddl}]PF6, ((S,S)-Et2eddl = O,O′-diethyl ester of ethylenediamine-N,N′-di-2-(4-methyl)pentanoic acid) was synthesized and characterized by IR, 1D (1H and 13C), and 2D (H,H-COSY and H,H-NOESY) NMR spectroscopy, mass spectrometry, and elemental analysis. Density functional theory calculations confirmed that (R,R)-N,N′ diastereoisomer was energetically the most stable isomer. In vitro antitumor action of ligand precursor [(S,S)-H2Et2eddl]Cl2 and corresponding gold(III) complex was determined against tumor cell lines: human adenocarcinoma (HeLa), human colon carcinoma (LS174), human breast cancer (MCF7), non-small cell lung carcinoma cell line (A549), and non-cancerous cell line human embryonic lung fibroblast (MRC-5) using microculture tetrazolium test (MTT) assay. The results indicate that both ligand precursor and gold(III) complex have showed very good to moderate cytotoxic activity against all tested malignant cell lines. The highest activity was expressed by [AuCl2{(S,S)-Et2eddl}]PF6 against the LS174 cells, with IC50 value of 7.4 ± 1.2 µM. A2 - C1 - Bioorganic Chemistry ER - TY - JOUR ID - 1014 TI - Chronic Toxoplasma gondii infection enhances β-amyloid phagocytosis and clearance by recruited monocytes JO - Acta Neuropathol. Commun. PY - 2016 SP - 25 AU - Möhle, L. AU - Israel, N. AU - Paarmann, K. AU - Krohn, M. AU - Pietkiewicz, S. AU - Müller, A. AU - Lavrik, I. N. AU - Buguliskis, J. S. AU - Schott, B. H. AU - Schlüter, D. AU - Gundelfinger, E. D. AU - Montag, D. AU - Seifert, U. AU - Pahnke, J. AU - Dunay, I. R. AU - VL - 4 UR - DO - 10.1186/s40478-016-0293-8 AB - IntroductionAlzheimer’s disease (AD) is associated with the accumulation of β-amyloid (Aβ) as senile plaques in the brain, thus leading to neurodegeneration and cognitive impairment. Plaque formation depends not merely on the amount of generated Aβ peptides, but more importantly on their effective removal. Chronic infections with neurotropic pathogens, most prominently the parasite Toxoplasma (T.) gondii, are frequent in the elderly, and it has been suggested that the resulting neuroinflammation may influence the course of AD. In the present study, we investigated how chronic T. gondii infection and resulting neuroinflammation affect plaque deposition and removal in a mouse model of AD.ResultsChronic infection with T. gondii was associated with reduced Aβ and plaque load in 5xFAD mice. Upon infection, myeloid-derived CCR2hi Ly6Chi monocytes, CCR2+ Ly6Cint, and CCR2+ Ly6Clow mononuclear cells were recruited to the brain of mice. Compared to microglia, these recruited mononuclear cells showed highly increased phagocytic capacity of Aβ ex vivo. The F4/80+ Ly6Clow macrophages expressed high levels of Triggering Receptor Expressed on Myeloid cells 2 (TREM2), CD36, and Scavenger Receptor A1 (SCARA1), indicating phagocytic activity. Importantly, selective ablation of CCR2+ Ly6Chi monocytes resulted in an increased amount of Aβ in infected mice. Elevated insulin-degrading enzyme (IDE), matrix metalloproteinase 9 (MMP9), as well as immunoproteasome subunits β1i/LMP2, β2i/MECL-1, and β5i/LMP7 mRNA levels in the infected brains indicated increased proteolytic Aβ degradation. Particularly, LMP7 was highly expressed by the recruited mononuclear cells in the brain, suggesting a novel mechanism of Aβ clearance.ConclusionsOur results indicate that chronic Toxoplasma infection ameliorates β-amyloidosis in a murine model of AD by activation of the immune system, specifically by recruitment of Ly6Chi monocytes and by enhancement of phagocytosis and degradation of soluble Aβ. Our findings provide evidence for a modulatory role of inflammation-induced Aβ phagocytosis and degradation by newly recruited peripheral immune cells in the pathophysiology of AD. A2 - C1 - Bioorganic Chemistry ER - TY - JOUR ID - 1013 TI - Biological Potential of Halfsandwich Ruthenium(II) and Iridium (III) Complexes JO - Anti-Cancer Agents Med. Chem. PY - 2016 SP - 1455-1460 AU - Ludwig, G. AU - Mojić, M. AU - Bulatović, M. AU - Mijatović, S. AU - Maksimović-Ivanić, D. AU - Steinborn, D. AU - Kaluđerović, G. N. AU - VL - 16 UR - DO - 10.2174/1871520615666151029100749 AB - In vitro studies with the ruthenium(II) and analogous iridium(III) complexes [Ru(η6- p-cymene)Cl2{Ph2PCH2CH2CH2S(O)xPh-κP}], [Ru(η6-p-cymene)Cl{Ph2PCH2CH2CH2S(O)xPh- κP,κS}][PF6] (1–4), [Ir(η5-C5Me5)Cl2{Ph2PCH2CH2CH2S(O)xPh-κP}] and [Ir(η5-C5Me5)Cl{Ph2 PCH2CH2CH2S(O)xPh-κP,κS}][PF6] (5–8; x = 0, 1) revealed the high selectivity toward the 8505C, A253, MCF-7, SW480 and 518A2 cancer cell lines. Thus, the cationic ruthenium complex 4 proved to be the most selective one. In case of the neutral and cationic ruthenium complexes 1–4 the caspase-dependent apoptotic cell death was proven as the main cause of the drug’s tumoricidal action on 8505C cell line. A2 - C1 - Bioorganic Chemistry ER - TY - JOUR ID - 1008 TI - Versatile antitumor potential of isoxanthohumol: Enhancement of paclitaxel activity in vivo JO - Pharmacol. Res. PY - 2016 SP - 62-73 AU - Krajnović, T. AU - Kaluđerović, G. N. AU - Wessjohann, L. A. AU - Mijatović, S. AU - Maksimović-Ivanić, D. AU - VL - 105 UR - DO - 10.1016/j.phrs.2016.01.011 AB - Isoxanthohumol (IXN), a prenylated flavonoid from hops, exhibits diverse biological activities, e.g. antitumor, antiinflammatory, antioxidant and antiangiogenic. In this study, the effect of IXN is evaluated on two melanoma cell lines with dissimilar molecular background, B16 and A375. The treatment of both cell lines with IXN resulted in dose-dependent decrease of cell viability. Abolished viability was in correlation with changed morphology and loss of dividing potential indicating phenotypical alteration of both tested cell lines. While modified B16 cells underwent the process of non-classic differentiation followed by tyrosinase activity without enhancement of melanin content, inhibition of Notch 1, β-catenin and Oct-3/4 was observed in A375 cells indicating loss of their pluripotent characteristics. In parallel with this, distinct subpopulations in both cell cultures entered the process of programmed cell death—apoptosis in a caspase independent manner. The described changes in cultures upon exposure to IXN could be connected with the suppression of reactive oxygen (ROS) and nitrogen species (RNS) induced by the drug. Despite the differences in which IXN promoted modifications in the upper part of the PI3K/Akt and MEK-ERK signaling pathways between B16 and A375 cells, p70S6K and its target S6 protein in both types of melanoma cells, after transient activation, became inhibited. In addition to direct input of IXN on cell viability, this study for the first time shows that IXN strongly sensitizes melanoma cells to the treatment with paclitaxel in vivo, in concordance with data obtained in vitro on B16 cells as well as their highly invasive F10 subclone. A2 - C1 - Bioorganic Chemistry ER - TY - JOUR ID - 1001 TI - Sideritis spp. Extracts Enhance Memory and Learning in Alzheimer’s β-Amyloidosis Mouse Models and Aged C57Bl/6 Mice JO - J. Alzheimers Dis. PY - 2016 SP - 967-980 AU - Hofrichter, J. AU - Krohn, M. AU - Schumacher, T. AU - Lange, C. AU - Feistel, B. AU - Walbroel, B. AU - Pahnke, J. AU - VL - 53 UR - DO - 10.3233/JAD-160301 AB - Nowadays, Alzheimer’s disease is the most prevalent epiphenomenon of the aging population. Although soluble amyloid-β (Aβ) species (monomers, oligomers) are recognized triggers of the disease, no therapeutic approach is able to stop it. Herbal medicines are used to treat different diseases in many regions of the world. On the Balkan Peninsula, at the eastern Mediterranean Sea, and adjacent regions, Sideritis species are used as traditional medicine to prevent age-related problems in elderly. To evaluate this traditional knowledge in controlled experiments, we tested extracts of two commonly used Sideritis species, Sideritis euboea and Sideritis scardica, with regard to their effects on cognition in APP-transgenic and aged, non-transgenic C57Bl/6 mice. Additionally, histomorphological and biochemical changes associated with Aβ deposition and treatment were assessed. We found that daily oral treatment with Sideritis spp. extracts highly enhanced cognition in aged, non-transgenic as well as in APP-transgenic mice, an effect that was even more pronounced when extracts of both species were applied in combination. The treatment strongly reduced Aβ42 load in APP-transgenic mice, accompanied by increased phagocytic activity of microglia, and increased expression of the α-secretase ADAM10. Moreover, the treatment was able to fully rescue neuronal loss of APP-transgenic mice to normal levels as seen in non-transgenic controls. Having the traditional knowledge in mind, our results imply that treatment with Sideritis spp. extracts might be a potent, well-tolerated option for treating symptoms of cognitive impairment in elderly and with regard to Alzheimer’s disease by affecting its most prominent hallmarks: Aβ pathology and cognitive decline. A2 - C1 - Bioorganic Chemistry ER - TY - JOUR ID - 993 TI - Site-specific analysis of advanced glycation end products in plasma proteins of type 2 diabetes mellitus patients JO - Anal. Bioanal. Chem. PY - 2016 SP - 5557-5566 AU - Greifenhagen, U. AU - Frolov, A. AU - Blüher, M. AU - Hoffmann, R. AU - VL - 408 UR - DO - 10.1007/s00216-016-9651-4 AB - Advanced glycation end products (AGEs) are posttranslational modifications formed non-enzymatically from the reaction of carbohydrates and their degradation products with proteins. Accumulation of AGEs is associated with the progression of severe diabetic complications, for example, and elevated tissue levels of AGEs might even predict these pathologies. As AGE formation is often site-specific, mapping of these modification sites may reveal more sensitive and specific markers than the global tissue level. Here, 42 AGE modifications were identified in a bottom-up proteomic approach by tandem mass spectrometry, which corresponded to 36 sites in 22 high to medium abundant proteins in individual plasma samples obtained from type 2 diabetes mellitus (T2DM) patients with long disease duration (>10 years). Major modifications were glarg (11 modification sites) and carboxymethylation (5) of arginine and formylation (8), acetylation (7), and carboxymethylation (7) of lysine residues. Relative quantification of these sites in plasma samples obtained from normoglycemic individuals (n = 47) and patients with T2DM being newly diagnosed (n = 47) or of medium (2–5 years, n = 20) and long disease duration (>10 years, n = 20) did not reveal any significant differences. A2 - C1 - Bioorganic Chemistry ER - TY - JOUR ID - 992 TI - Immobilized metal affinity chromatography on collapsed Langmuir-Blodgett iron(III) stearate films and iron(III) oxide nanoparticles for bottom-up phosphoproteomics JO - J. Chromatogr. A PY - 2016 SP - 181-190 AU - Gladilovich, V. AU - Greifenhagen, U. AU - Sukhodolov, N. AU - Selyutin, A. AU - Singer, D. AU - Thieme, D. AU - Majovsky, P. AU - Shirkin, A. AU - Hoehenwarter, W. AU - Bonitenko, E. AU - Podolskaya, E. AU - Frolov, A. AU - VL - 1443 UR - DO - 10.1016/j.chroma.2016.03.044 AB - Phosphorylation is the enzymatic reaction of site-specific phosphate transfer from energy-rich donors to the side chains of serine, threonine, tyrosine, and histidine residues in proteins. In living cells, reversible phosphorylation underlies a universal mechanism of intracellular signal transduction. In this context, analysis of the phosphoproteome is a prerequisite to better understand the cellular regulatory networks. Conventionally, due to the low contents of signaling proteins, selective enrichment of proteolytic phosphopeptides by immobilized metal affinity chromatography (IMAC) is performed prior to their LC–MS or -MS/MS analysis. Unfortunately, this technique still suffers from low selectivity and compromised analyte recoveries. To overcome these limitations, we propose IMAC systems comprising stationary phases based on collapsed Langmuir-Blodgett films of iron(III) stearate (FF) or iron(III) oxide nanoparticles (FO) and mobile phases relying on ammonia, piperidine and heptadecafluorooctanesulfonic acid (PFOS). Experiments with model phosphopeptides and phosphoprotein tryptic digests showed superior binding capacity, selectivity and recovery for both systems in comparison to the existing commercial analogs. As evidenced by LC–MS/MS analysis of the HeLa phosphoproteome, these features of the phases resulted in increased phosphoproteome coverage in comparison to the analogous commercially available phases, indicating that our IMAC protocol is a promising chromatographic tool for in-depth phosphoproteomic research. A2 - C1 - Bioorganic Chemistry ER - TY - JOUR ID - 1044 TI - Revisiting rodent models: Octodon degus as Alzheimer’s disease model? JO - Acta Neuropathol. Commun. PY - 2016 SP - 91 AU - Steffen, J. AU - Krohn, M. AU - Paarmann, K. AU - Schwitlick, C. AU - Brüning, T. AU - Marreiros, R. AU - Müller-Schiffmann, A. AU - Korth, C. AU - Braun, K. AU - Pahnke, J. AU - VL - 4 UR - DO - 10.1186/s40478-016-0363-y AB - Alzheimer’s disease primarily occurs as sporadic disease and is accompanied with vast socio-economic problems. The mandatory basic research relies on robust and reliable disease models to overcome increasing incidence and emerging social challenges. Rodent models are most efficient, versatile, and predominantly used in research. However, only highly artificial and mostly genetically modified models are available. As these ‘engineered’ models reproduce only isolated features, researchers demand more suitable models of sporadic neurodegenerative diseases. One very promising animal model was the South American rodent Octodon degus, which was repeatedly described as natural ‘sporadic Alzheimer’s disease model’ with ‘Alzheimer’s disease-like neuropathology’. To unveil advantages over the ‘artificial’ mouse models, we re-evaluated the age-dependent, neurohistological changes in young and aged Octodon degus (1 to 5-years-old) bred in a wild-type colony in Germany. In our hands, extensive neuropathological analyses of young and aged animals revealed normal age-related cortical changes without obvious signs for extensive degeneration as seen in patients with dementia. Neither significant neuronal loss nor enhanced microglial activation were observed in aged animals. Silver impregnation methods, conventional, and immunohistological stains as well as biochemical fractionations revealed neither amyloid accumulation nor tangle formation. Phosphoepitope-specific antibodies against tau species displayed similar intraneuronal reactivity in both, young and aged Octodon degus.In contrast to previous results, our study suggests that Octodon degus born and bred in captivity do not inevitably develop cortical amyloidosis, tangle formation or neuronal loss as seen in Alzheimer’s disease patients or transgenic disease models. A2 - C1 - Bioorganic Chemistry ER - TY - JOUR ID - 1041 TI - Combinatorial synthesis, in silico, molecular and biochemical studies of tetrazole-derived organic selenides with increased selectivity against hepatocellular carcinoma JO - Eur. J. Med. Chem. PY - 2016 SP - 55-71 AU - Shaaban, S. AU - Negm, A. AU - Ashmawy, A. M. AU - Ahmed, D. M. AU - Wessjohann, L. A. AU - VL - 122 UR - DO - 10.1016/j.ejmech.2016.06.005 AB - Novel tetrazole-based diselenides and selenoquinones were synthesized via azido-Ugi and sequential nucleophilic substitution (SN) strategy. Molecular docking study into mammalian TrxR1 was used to predict the anticancer potential of the newly synthesized compounds. The cytotoxic activity of the compounds was evaluated using hepatocellular carcinoma (HepG2) and breast adenocarcinoma (MCF-7) cancer cells and compared with their cytotoxicity in normal fibroblast (WI-38) cells. The corresponding redox properties of the synthesized compounds were assessed employing 2,2-diphenyl-1-picrylhydrazyl (DPPH), glutathione peroxidase (GPx)-like activity and bleomycin dependent DNA damage. In general, diselenides showed preferential cytotoxicity to HepG2 compared to MCF-7 cells. These compounds exhibited also good GPx catalytic activity compared to ebselen (up to 5 fold). Selenoquinones 18, 21, 22 and 23 were selected to monitor the expression levels of caspase-8, Bcl-2 and Ki-67 molecular biomarkers. Interestingly, these compounds downregulated the Bcl-2 and Ki-67 expression levels and activated the expression of caspase-8 in HepG2 cells compared to untreated cells. These results indicate that some of the newly synthesized compounds possess anti-HepG2 activity. A2 - C1 - Bioorganic Chemistry ER - TY - JOUR ID - 1027 TI - Osmotic stress is accompanied by protein glycation in Arabidopsis thaliana JO - J. Exp. Bot. PY - 2016 SP - 6283-6295 AU - Paudel, G. AU - Bilova, T. AU - Schmidt, R. AU - Greifenhagen, U. AU - Berger, R. AU - Tarakhovskaya, E. AU - Stöckhardt, S. AU - Balcke, G. U. AU - Humbeck, K. AU - Brandt, W. AU - Sinz, A. AU - Vogt, T. AU - Birkemeyer, C. AU - Wessjohann, L. AU - Frolov, A. AU - VL - 67 UR - DO - 10.1093/jxb/erw395 AB - Among the environmental alterations accompanying oncoming climate changes, drought is the most important factor influencing crop plant productivity. In plants, water deficit ultimately results in the development of oxidative stress and accumulation of osmolytes (e.g. amino acids and carbohydrates) in all tissues. Up-regulation of sugar biosynthesis in parallel to the increasing overproduction of reactive oxygen species (ROS) might enhance protein glycation, i.e. interaction of carbonyl compounds, reducing sugars and α-dicarbonyls with lysyl and arginyl side-chains yielding early (Amadori and Heyns compounds) and advanced glycation end-products (AGEs). Although the constitutive plant protein glycation patterns were characterized recently, the effects of environmental stress on AGE formation are unknown so far. To fill this gap, we present here a comprehensive in-depth study of the changes in Arabidopsis thaliana advanced glycated proteome related to osmotic stress. A 3 d application of osmotic stress revealed 31 stress-specifically and 12 differentially AGE-modified proteins, representing altogether 56 advanced glycation sites. Based on proteomic and metabolomic results, in combination with biochemical, enzymatic and gene expression analysis, we propose monosaccharide autoxidation as the main stress-related glycation mechanism, and glyoxal as the major glycation agent in plants subjected to drought. A2 - C1 - Cell and Metabolic Biology; Bioorganic Chemistry ER - TY - JOUR ID - 1026 TI - Electrochemical properties of some gold(III) complexes with (S,S)-R2edda-type ligands JO - Int. J. Electrochem. Sci. PY - 2016 SP - 1162-1171 AU - Pantelić, N. AU - Stanković, D. M. AU - Zmejkovski, B. B. AU - Kaluđerović, G. N. AU - Sabo, T. J. AU - VL - 11 UR - http://www.electrochemsci.org/list16.htm#issue2 AB - Oxidation-reduction properties of eleven gold(III) complexes with (S,S)-R2edda-type ligands was studied by cyclic and differential pulse voltammetry in DMSO. Series I: [AuCl2{(S,S)-R2eddip}]PF6, (S,S)-eddip = (S,S)-ethylenediamine-N,N’-di-2-propanoate, R = n-butyl, n-pentyl, isobutyl, isoamyl, cyclopentyl, 1–5; II: [AuCl2{(S,S)-R2eddch}]PF6, (S,S)-eddch = (S,S)-ethylenediamine-N,N’-di-2-(3-cyclohexyl)propanoate, R = methyl, ethyl, n-propyl, n-butyl, isobutyl, isoamyl, 6–11. Voltammograms in DMSO showed two successive irreversible reduction steps, where AuI species were the final reduction product. Reduction potential values are in range from 116 to 156 mV (Ep1) and –520 to –572 mV (Ep2) for Series I and from 148 to 228 mV (Ep1) and –569 to –638 mV (Ep2) for Series II. In general, slightly easier reduction of complexes belonging to Series I (higher cytotoxicity) could be due to less steric hindrance around the gold center. Reduction potentials and anticancer activity are not in correlation. A2 - C1 - Bioorganic Chemistry ER - TY - JOUR ID - 977 TI - SBA-15 mesoporous silica particles loaded with cisplatin induce senescence in B16F10 cells JO - RSC Adv. PY - 2016 SP - 111031-111040 AU - Edeler, D. AU - Kaluđerović, M. R. AU - Dojčinović, B. AU - Schmidt, H. AU - Kaluđerović, G. N. AU - VL - 6 UR - DO - 10.1039/C6RA22596A AB - The anticancer drug cisplatin (CP) is loaded into SBA-15 mesoporous silica (SBA-15|CP) and its release from the nanomaterial is studied. The CP-loaded SBA-15 is tested against four tumor cell lines: mouse malignant melanoma B16F10, human adenocarcinoma HeLa, colon HT-29 and prostate PC3. Most importantly, the superiority of this novel material in comparison to CP arises from the fact that the CP-grafted nanomaterial SBA-15 (→SBA-15|CP) is enhancing cessation of proliferation along with induction of senescence in B16F10 in approximately 3.5 times lower concentration. The control material loaded with therapeutically inactive K2[PtCl4] (→SBA-15|TC) showed no antitumor activity. To a large extent, SBA-15|CP-induced senescence might present a safe approach in tumor treatment. Such cells can be cleared by immune cells resulting in efficient tumor regression. So far only apoptotic agents are being exploited in clinics, thus an understanding of the chemotherapeutic-induced senescence will allow oncologists to explore this essential tumor suppressor mechanism. A2 - C1 - Bioorganic Chemistry ER - TY - JOUR ID - 966 TI - A Snapshot of the Plant Glycated Proteome: STRUCTURAL, FUNCTIONAL, AND MECHANISTIC ASPECTS JO - J. Biol. Chem. PY - 2016 SP - 7621-7636 AU - Bilova, T. AU - Lukasheva, E. AU - Brauch, D. AU - Greifenhagen, U. AU - Paudel, G. AU - Tarakhovskaya, E. AU - Frolova, N. AU - Mittasch, J. AU - Balcke, G. U. AU - Tissier, A. AU - Osmolovskaya, N. AU - Vogt, T. AU - Wessjohann, L. A. AU - Birkemeyer, C. AU - Milkowski, C. AU - Frolov, A. AU - VL - 291 UR - DO - 10.1074/jbc.M115.678581 AB - Glycation is the reaction of carbonyl compounds (reducing sugars and α-dicarbonyls) with amino acids, lipids, and proteins, yielding early and advanced glycation end products (AGEs). The AGEs can be formed via degradation of early glycation intermediates (glycoxidation) and by interaction with the products of monosaccharide autoxidation (autoxidative glycosylation). Although formation of these potentially deleterious compounds is well characterized in animal systems and thermally treated foods, only a little information about advanced glycation in plants is available. Thus, the knowledge of the plant AGE patterns and the underlying pathways of their formation are completely missing. To fill this gap, we describe the AGE-modified proteome of Brassica napus and characterize individual sites of advanced glycation by the methods of liquid chromatography-based bottom-up proteomics. The modification patterns were complex but reproducible: 789 AGE-modified peptides in 772 proteins were detected in two independent experiments. In contrast, only 168 polypeptides contained early glycated lysines, which did not resemble the sites of advanced glycation. Similar observations were made with Arabidopsis thaliana. The absence of the early glycated precursors of the AGE-modified protein residues indicated autoxidative glycosylation, but not glycoxidation, as the major pathway of AGE formation. To prove this assumption and to identify the potential modifying agents, we estimated the reactivity and glycative potential of plant-derived sugars using a model peptide approach and liquid chromatography-mass spectrometry-based techniques. Evaluation of these data sets together with the assessed tissue carbohydrate contents revealed dihydroxyacetone phosphate, glyceraldehyde 3-phosphate, ribulose, erythrose, and sucrose as potential precursors of plant AGEs. A2 - C1 - Cell and Metabolic Biology; Bioorganic Chemistry ER - TY - JOUR ID - 965 TI - Morphometric analysis of the cerebral expression of ATP-binding cassette transporter protein ABCB1 in chronic schizophrenia: Circumscribed deficits in the habenula JO - Schizophr. Res. PY - 2016 SP - 52-58 AU - Bernstein, H.-G. AU - Hildebrandt, J. AU - Dobrowolny, H. AU - Steiner, J. AU - Bogerts, B. AU - Pahnke, J. AU - VL - 177 UR - DO - 10.1016/j.schres.2016.02.036 AB - There is increasing evidence that microvascular abnormalities and malfunction of the blood–brain barrier (BBB) significantly contribute to schizophrenia pathophysiology. The ATP-binding cassette transporter ABCB1 is an important molecular component of the intact BBB, which has been implicated in a number of neurodegenerative and psychiatric disorders, including schizophrenia. However, the regional and cellular expression of ABCB1 in schizophrenia is yet unexplored. Therefore, we studied ABCB1 protein expression immunohistochemically in twelve human post-mortem brain regions known to play a role in schizophrenia, in 13 patients with schizophrenia and nine controls. In ten out of twelve brain regions under study, no significant differences were found with regard to the numerical density of ABCB1-expressing capillaries between all patients with schizophrenia and control cases. The left and right habenular complex, however, showed significantly reduced capillary densities in schizophrenia patients. In addition, we found a significantly reduced density of ABCB1-expressing neurons in the left habenula. Reduced ABCB1 expression in habenular capillaries might contribute to increased brain levels of proinflammatory cytokines in patients with schizophrenia, while decreased expression of this protein in a subpopulation of medial habenular neurons (which are probably purinergic) might be related to abnormalities of purines and their receptors found in this disease. A2 - C1 - Bioorganic Chemistry ER - TY - JOUR ID - 963 TI - Evaluation of functionalized mesoporous silica SBA-15 as a carrier system for Ph3Sn(CH2)3OH against the A2780 ovarian carcinoma cell line JO - Dalton Trans. PY - 2016 SP - 18984-18993 AU - Bensing, C. AU - Mojić, M. AU - Gómez-Ruiz, S. AU - Carralero, S. AU - Dojčinović, B. AU - Maksimović-Ivanić, D. AU - Mijatović, S. AU - Kaluđerović, G. N. AU - VL - 45 UR - DO - 10.1039/C6DT03519A AB - SBA-15|Sn3, a mesoporous silica-based material (derivative of SBA-15) loaded with an organotin compound Ph3Sn(CH2)3OH (Sn3), possesses improved antitumor potential against the A2780 high-grade serous ovarian carcinoma cell line in comparison to Sn3. It is demonstrated that both the compound and the nanostructured material are internalized by the A2780 cells. A similar mode of action of Sn3 and SBA-15|Sn3 against the A2780 cell line was found. Explicitly, induction of apoptosis, caspase 2, 3, 8 and 9 activation, accumulation of cells in the hypodiploid phase as well as accumulation of ROS were observed. Interestingly, Sn3 loaded in the mesoporous silica-based material needed to reach a concentration 3.5 times lower than the IC50 value of the Sn3 compound, pointing out a higher effect of the SBA-15|Sn3 than Sn3 alone. Clonogenic potential, growth in 3D culture as well as mobility of cells were disturbed in the presence of SBA-15|Sn3. Such behavior could be associated with the suppression of p-38 MAPK. Less profound effect of Sn3 compared to SBA-15|Sn3 could be attributed to a different regulation of p-38 and STAT-3, which are mainly responsible for an appropriate cellular response to diverse stimuli or metastatic properties. A2 - C1 - Bioorganic Chemistry ER - TY - JOUR ID - 959 TI - Bioactive Triterpenes from the Fungus Piptoporus betulinus JO - Rec. Nat. Prod. PY - 2016 SP - 103-108 AU - Alresly, Z. AU - Lindequist, U. AU - Lalk, M. AU - Porzel, A. AU - Arnold, N. AU - Wessjohann, L. A. AU - VL - 10 UR - http://www.acgpubs.org/article/records-of-natural-products/2016/1-january-february/bioactive-triterpenes-from-the-fungus-piptoporus-betulinus AB - Phytochemical investigation of the ethyl acetate extract of the fruiting bodies from the basidiomycete Piptoporus betulinus led to the isolation of a new bioactive lanostane triterpene identified as 3 b -acetoxy-16-hydroxy-24-oxo-5α-lanosta-8- ene-21-oic acid (1). In addition, ten known triterpenes, polyporenic acid A (5), polyporenic acid C (4), three derivatives of polyporenic acid A (8, 10, 11), betulinic acid (3), betulin (2), ergosterol peroxide (6), 9,11-dehydroergosterol peroxide (7), and fomefficinic acid (9), were also isolated from the fungus. All isolated compounds were tested for antimicrobial activity against some Gram-positive and Gram-negative bacteria as well as against a fungal strain. The new triterpene and some of the other compounds showed antimicrobial activity against Gram-positive bacteria. A2 - C1 - Bioorganic Chemistry ER - TY - JOUR ID - 987 TI - Activation of Mitochondrial Complex II-Dependent Respiration Is Beneficial for α-Synucleinopathies JO - Mol. Neurobiol. PY - 2016 SP - 4728-4744 AU - Fröhlich, C. AU - Zschiebsch, K. AU - Gröger, V. AU - Paarmann, K. AU - Steffen, J. AU - Thurm, C. AU - Schropp, E.-M. AU - Brüning, T. AU - Gellerich, F. AU - Radloff, M. AU - Schwabe, R. AU - Lachmann, I. AU - Krohn, M. AU - Ibrahim, S. AU - Pahnke, J. AU - VL - 53 UR - DO - 10.1007/s12035-015-9399-4 AB - Parkinson’s disease and dementia with Lewy bodies are major challenges in research and clinical medicine world-wide and contribute to the most common neurodegenerative disorders. Previously, specific mitochondrial polymorphisms have been found to enhance clearance of amyloid-β from the brain of APP-transgenic mice leading to beneficial clinical outcome. It has been discussed whether specific mitochondrial alterations contribute to disease progression or even prevent toxic peptide deposition, as seen in many neurodegenerative diseases. Here, we investigated α-synuclein-transgenic C57BL/6J mice with the A30P mutation, and a novel A30P C57BL/6J mouse model with three mitochondrial DNA polymorphisms in the ND3, COX3 and mtRNAArg genes, as found in the inbred NOD/LtJ mouse strain. We were able to detect that the new model has increased mitochondrial complex II-respiration which occurs in parallel to neuronal loss and improved motor performance, although it exhibits higher amounts of high molecular weight species of α-synuclein. High molecular weight aggregates of different peptides are controversially discussed in the light of neurodegeneration. A favourable hypothesis states that high molecular weight species are protective and of minor importance for the pathogenesis of neurodegenerative disorders as compared to the extreme neurotoxic monomers and oligomers. Summarising, our results point to a potentially protective and beneficial effect of specific mitochondrial polymorphisms which cause improved mitochondrial complex II-respiration in α-synucleinopathies, an effect that could be exploited further for pharmaceutical interventions. A2 - C1 - Bioorganic Chemistry ER - TY - CHAP ID - 46 TI - Glycation of Plant Proteins under Environmental Stress — Methodological Approaches, Potential Mechanisms and Biological Role T2 - Abiotic and Biotic Stress in Plants - Recent Advances and Future Perspectives PB - PY - 2016 SP - 295-316 AU - Bilova, T. AU - Greifenhagen, U. AU - Paudel, G. AU - Lukasheva, E. AU - Brauch, D. AU - Osmolovskaya, N. AU - Tarakhovskaya, E. AU - Balcke, G. U. AU - Tissier, A. AU - Vogt, T. AU - Milkowski, C. AU - Birkemeyer, C. AU - Wessjohann, L. AU - Frolov, A. AU - VL - UR - DO - 10.5772/61860 AB - Environmental stress is one of the major factors reducing crop productivity. Due to the oncoming climate changes, the effects of drought and high light on plants play an increasing role in modern agriculture. These changes are accompanied with a progressing contamination of soils with heavy metals. Independent of their nature, environmental alterations result in development of oxidative stress, i.e. increase of reactive oxygen species (ROS) contents, and metabolic adjustment, i.e. accumulation of soluble primary metabolites (amino acids and sugars). However, a simultaneous increase of ROS and sugar concentrations ultimately results in protein glycation, i.e. non-enzymatic interaction of reducing sugars or their degradation products (α-dicarbonyls) with proteins. The eventually resulting advanced glycation end-products (AGEs) are known to be toxic and pro-inflammatory in mammals. Recently, their presence was unambiguously demonstrated in vivo in stressed Arabidopsis thaliana plants. Currently, information on protein targets, modification sites therein, mediators and mechanisms of plant glycation are being intensively studied. In this chapter, we comprehensively review the methodological approaches for plant glycation research and discuss potential mechanisms of AGE formation under stress conditions. On the basis of these patterns and additional in vitro experiments, the pathways and mechanisms of plant glycation can be proposed. A2 - Shanker, A. K. & Shanker, C., eds. C1 - Cell and Metabolic Biology; Bioorganic Chemistry ER - TY - JOUR ID - 1153 TI - Isolation and anticancer, anthelminthic, and antiviral (HIV) activity of acylphloroglucinols, and regioselective synthesis of empetrifranzinans from Hypericum roeperianum JO - Bioorg. Med. Chem. PY - 2015 SP - 6327-6334 AU - Tanemossu Fobofou, S. A. AU - Franke, K. AU - Sanna, G. AU - Porzel, A. AU - Bullita, E. AU - La Colla, P. AU - Wessjohann, L. A. AU - VL - 23 UR - DO - 10.1016/j.bmc.2015.08.028 AB - From the ethno-medicinally used leaves of Hypericum roeperianum we isolated a new tricyclic acylphloroglucinol (1), a new tetracyclic acylphloroglucinol (2), and a new prenylated bicyclic acylphloroglucinol (3) together with four known prenylated (4–7) and three known tetracyclic acylphloroglucinol derivatives (8–10). Structure elucidation was based on UV, IR, [α]D25, 1D- and 2D-NMR experiments. Furthermore, empetrifranzinans A (8) and C (9) were synthesized regioselectively in only two steps. The isolated compounds were evaluated for their cytotoxicity against PC-3 and HT-29 cancer cell lines as well as antibacterial and anthelmintic activities. They were also tested in cell-based assays for cytotoxicity against MT-4 cells and for anti-HIV activity in infected MT-4 cells. Significant anthelmintic activity against Caenorhabditis elegans was exhibited by compound 7 (3-geranyl-1-(2′-methylbutanoyl)-phloroglucinol), which might provide a new lead. A2 - C1 - Bioorganic Chemistry ER - TY - JOUR ID - 1135 TI - In vitro anticancer activity of gold(III) complexes with some esters of (S,S)-ethylenediamine-N,N′-di-2-propanoic acid JO - Eur. J. Med. Chem. PY - 2015 SP - 766-774 AU - Pantelić, N. AU - Stanojković, T. P. AU - Zmejkovski, B. B. AU - Sabo, T. J. AU - Kaluđerović, G. N. AU - VL - 90 UR - DO - 10.1016/j.ejmech.2014.12.019 AB - Five novel gold(III) complexes of general formulas [AuCl2{(S,S)-R2eddip}]PF6, ((S,S)-eddip = (S,S)-ethylenediamine-N,N′-di-2-propanoate, R = n-Bu, n-Pe, i-Bu, i-Am, cPe; 1–5, respectively) were synthesized and characterized by UV/Vis, IR and NMR spectroscopy and mass spectrometry. DFT calculations indicated that (R,R)-N,N′-configuration diastereoisomers were the most stable for 1–5. 3 is stable in DMSO for at least 24 h, but immediate hydrolysis in PBS occurs. 3 is readily reduced with ascorbic acid and forms adducts with bovine serum albumin (BSA). In vitro anticancer activity of the gold(III) complexes against human cervix adenocarcinoma HeLa, human myelogenous leukemia K562, human melanoma Fem-x tumor cell lines, as well as against non-cancerous human embryonic lung fibroblast cell line MRC-5 was determined using MTT assay. Complex 4 showed highest activity and selectivity (IC50(Fem-x) = 1.3 ± 0.2; IC50(MRC-5)/IC50(Fem-x) = 72.5 ± 12.4), 4 times more active and 28 times more selective than cisplatin. Complexes induced apoptotic mode of death in a time-dependent manner in HeLa cells. A2 - C1 - Bioorganic Chemistry ER - TY - JOUR ID - 1126 TI - In vitro effects of binuclear (η6-p-cymene)ruthenium(II) complex containing bridging bis(nicotinate)-polyethylene glycol ester ligand on differentiation pathways of murine Th lymphocytes activated by T cell mitogen JO - J. Biol. Inorg. Chem. PY - 2015 SP - 575-583 AU - Momčilović, M. AU - Eichhorn, T. AU - Blazevski, J. AU - Schmidt, H. AU - Kaluđerović, G. N. AU - Stosic-Grujicic, S. AU - VL - 20 UR - DO - 10.1007/s00775-015-1242-x AB - T cell differentiation into distinct T helper (Th) subpopulations is crucial in governing acquired immune responses as well as some inflammatory and autoimmune disorders. This study investigated potential of the novel neutral binuclear ruthenium(II) complexes 1–8 with general formula [{RuCl2(η6-p-cym)}2μ-(N∩N)] (N∩N = bis(nicotinate)- and bis(iso-nicotinate)-polyethylene glycol esters; (3-py)COO(CH2CH2O) n CO(3-py) and (4-py)COO(CH2CH2O) n CO(4-py); n = 1–4), as well as [RuCl2(η6-p-cym)(nic)] (R1, nic = nicotinate) and [RuCl2(η6-p-cym)(inic)] (R2, inic = isonicotinate) as an immunomodulatory agents capable to direct Th cell differentiation. From all investigated complexes, [{RuCl2(η6-p-cym)}2μ-{(3-py)COO(CH2CH2O)4CO(3-py)}] (4) was selected for further study because it did not affect splenocyte viability (in concentration up to 50 μM), but significantly reduced secretion of representative Th1 cytokine, IFN-γ induced by T cell mitogen. Besides IFN-γ, 4 inhibited dose dependently expression and production of representative Th17 cytokine, IL-17, in these cells. Otherwise, the production of anti-inflammatory cytokines IL-4 and IL-10 was upregulated. Also, 4 significantly increased CD4+CD25+FoxP3+ Treg cell frequency in the activated splenocytes. Moreover, ConA-induced expression of Th1 transcription factors, T-bet and STAT1, as well as of Th17-related protein STAT3 was attenuated upon exposure to 4, while the expression of Th2-related transcription factor GATA3 remained stable. In conclusion, ruthenium(II) complex 4 modulates immune system cell functions in vitro by inhibiting T cell differentiation towards pathogenic Th1/Th17 phenotype and inducing a regulatory phenotype characterized by IL-10 and IL-4 production, which may provide novel therapeutic opportunities for immune-inflammatory and/or autoimmune disorders. A2 - C1 - Bioorganic Chemistry ER - TY - JOUR ID - 1125 TI - A fluorescence-based bioassay for antibacterials and its application in screening natural product extracts JO - J. Antibiot. PY - 2015 SP - 734-740 AU - Michels, K. AU - Heinke, R. AU - Schöne, P. AU - Kuipers, O. P. AU - Arnold, N. AU - Wessjohann, L. A. AU - VL - 68 UR - DO - 10.1038/ja.2015.71 AB - The reliable assessment of the biological activity of a minor component embedded in a complex matrix of several hundred compounds is a difficult but common task in the search for natural product-based antibiotics, for example, by bioassay-guided fractionation. To quantify the antibiotic properties, it is necessary to assess the cell viability. Direct measurements use CFU counts, OD measurements or detection via fluorescent or reducible dyes. However, natural extracts often already possess intrinsic dye, fluorescent, reducing or protein denaturing properties, or they contain insoluble compounds or general protein-binding (tanning) polyphenols as disturbing features, while at the same time very little of the selective antibiotic sought after is present. A promising alternative is provided by intrinsically produced bright fluorescent proteins. In this paper, a rapid, robust and concentration-dependent assay for screening antibiotics with genetically modified mutants of Bacillus subtilis 168 (PabrB-iyfp) is presented. The Gram-positive bacteria exhibit a native fluorescence during their exponential growth phase due to the expression of improved yellow fluorescent protein. To demonstrate the applicability in the field of natural product research, several compounds and extracts were screened for antibacterial activity, with an emphasis on those from the fungal genus Hygrophorus (waxy caps). A2 - C1 - Bioorganic Chemistry ER - TY - JOUR ID - 1115 TI - Hydrogen peroxide – production, fate and role in redox signaling of tumor cells JO - Cell Commun. Signal. PY - 2015 SP - AU - Lennicke, C. AU - Rahn, J. AU - Lichtenfels, R. AU - Wessjohann, L. A. AU - Seliger, B. AU - VL - 13 UR - DO - 10.1186/s12964-015-0118-6 AB - Hydrogen peroxide (H2O2) is involved in various signal transduction pathways and cell fate decisions. The mechanism of the so called “redox signaling” includes the H2O2-mediated reversible oxidation of redox sensitive cysteine residues in enzymes and transcription factors thereby altering their activities. Depending on its intracellular concentration and localization, H2O2 exhibits either pro- or anti-apoptotic activities. In comparison to normal cells, cancer cells are characterized by an increased H2O2 production rate and an impaired redox balance thereby affecting the microenvironment as well as the anti-tumoral immune response. This article reviews the current knowledge about the intracellular production of H2O2 along with redox signaling pathways mediating either the growth or apoptosis of tumor cells. In addition it will be discussed how the targeting of H2O2-linked sources and/or signaling components involved in tumor progression and survival might lead to novel therapeutic targets. A2 - C1 - Bioorganic Chemistry ER - TY - JOUR ID - 1111 TI - Accumulation of murine amyloid-β mimics early Alzheimer’s disease JO - Brain PY - 2015 SP - 2370-2382 AU - Krohn, M. AU - Bracke, A. AU - Avchalumov, Y. AU - Schumacher, T. AU - Hofrichter, J. AU - Paarmann, K. AU - Fröhlich, C. AU - Lange, C. AU - Brüning, T. AU - von Bohlen und Halbach, O. AU - Pahnke, J. AU - VL - 138 UR - DO - 10.1093/brain/awv137 AB - Amyloidosis mouse models of Alzheimer’s disease are generally established by transgenic approaches leading to an overexpression of mutated human genes that are known to be involved in the generation of amyloid-β in Alzheimer’s families. Although these models made substantial contributions to the current knowledge about the ‘amyloid hypothesis’ of Alzheimer’s disease, the overproduction of amyloid-β peptides mimics only inherited (familiar) Alzheimer’s disease, which accounts for <1% of all patients with Alzheimer’s disease. The inherited form is even regarded a ‘rare’ disease according to the regulations for funding of the European Union (www.erare.eu). Here, we show that mice that are double-deficient for neprilysin (encoded by Mme), one major amyloid-β-degrading enzyme, and the ABC transporter ABCC1, a major contributor to amyloid-β clearance from the brain, develop various aspects of sporadic Alzheimer’s disease mimicking the clinical stage of mild cognitive impairment. Using behavioural tests, electrophysiology and morphological analyses, we compared different ABC transporter-deficient animals and found that alterations are most prominent in neprilysin × ABCC1 double-deficient mice. We show that these mice have a reduced probability to survive, show increased anxiety in new environments, and have a reduced working memory performance. Furthermore, we detected morphological changes in the hippocampus and amygdala, e.g. astrogliosis and reduced numbers of synapses, leading to defective long-term potentiation in functional measurements. Compared to human, murine amyloid-β is poorly aggregating, due to changes in three amino acids at N-terminal positions 5, 10, and 13. Interestingly, our findings account for the action of early occurring amyloid-β species/aggregates, i.e. monomers and small amyloid-β oligomers. Thus, neprilysin × ABCC1 double-deficient mice present a new model for early effects of amyloid-β-related mild cognitive impairment that allows investigations without artificial overexpression of inherited Alzheimer’s disease genes. A2 - C1 - Bioorganic Chemistry ER - TY - JOUR ID - 1105 TI - Ruthenium(II) p-cymene complex bearing 2,2′-dipyridylamine targets caspase 3 deficient MCF-7 breast cancer cells without disruption of antitumor immune response JO - J. Inorg. Biochem. PY - 2015 SP - 315-321 AU - Kaluđerović, G. N. AU - Krajnović, T. AU - Momčilović, M. AU - Stosic-Grujicic, S. AU - Mijatović, S. AU - Maksimović-Ivanić, D. AU - Hey-Hawkins, E. AU - VL - 153 UR - DO - 10.1016/j.jinorgbio.2015.09.006 AB - [Ru(η6-p-cym)Cl{dpa(CH2)4COOEt}][PF6] (cym = cymene; dpa = 2,2′-dipyridylamine; complex 2) was prepared and characterized by elemental analysis, IR and multinuclear NMR spectroscopy, as well as ESI-MS and X-ray structural analysis. The structural analog without a side chain [Ru(η6-p-cym)Cl(dpa)][PF6] (1) as well as 2 were investigated in vitro against 518A2, SW480, 8505C, A253 and MCF-7 cell lines. Complex 1 is active against all investigated tumor cell lines while the activity of compound 2 is limited only to caspase 3 deficient MCF-7 breast cancer cells, however, both are less active than cisplatin. As CD4+ Th cells are necessary to trigger all the immune effector mechanisms required to eliminate tumor cells, besides testing the in vitro antitumor activity of 1 and 2, the effect of ruthenium(II) complexes on the cells of the adaptive immune system have also been evaluated. Importantly, complex 1 applied in concentrations which were effective against tumor cells did not affect immune cell viability, nor did exert a general immunosuppressive effect on cytokine production. Thus, beneficial characteristics of 1 might contribute to the overall therapeutic properties of the complex. A2 - C1 - Bioorganic Chemistry ER - TY - JOUR ID - 1079 TI - Improved in vitro antitumor potential of (O,O′-Diisobutyl-ethylenediamine-N,N′-di-3-propionate)tetrachloridoplatinum(IV) complex under normoxic and hypoxic conditions JO - Eur. J. Pharmacol. PY - 2015 SP - 136-144 AU - Bulatović, M. AU - Kaluđerović, M. R. AU - Mojić, M. AU - Zmejkovski, B. B. AU - Hey-Hawkins, E. AU - Vidaković, M. AU - Grdović, N. AU - Kaluđerović, G. N. AU - Mijatović, S. AU - Maksimović-Ivanić, D. AU - VL - 760 UR - DO - 10.1016/j.ejphar.2015.04.012 AB - (O,O′-Diisobutyl-ethylenediamine-N,N′-di-3-propionate)tetrachloridoplatinum(IV), [PtCl4(iBu2eddp)], shows an improved pharmacological profile in comparison to cisplatin. This is manifested through accelerated dying process led by necrotic cell death, reflected through mitochondrial collapse, strong ATP depletion and reactive oxygen species production. Loss of mitochondrial potential was further followed with intensive apoptosis that finalized with DNA fragmentation.Different dynamic of tumoricidal action could be partly ascribed to less affected repair mechanisms in comparison to cisplatin. Importantly, [PtCl4(iBu2eddp)] did not induce necrosis in primary fibroblasts suggesting different intracellular response of normal vs. tumor cells. This selectivity toward malignant phenotype is further confirmed by retained tumoricidal potential in hypoxic conditions, while cisplatin became completely inefficient. A2 - C1 - Bioorganic Chemistry ER - TY - JOUR ID - 1070 TI - Screening of synthetic and natural product databases: Identification of novel androgens and antiandrogens JO - Eur. J. Med. Chem. PY - 2015 SP - 267-279 AU - Bobach, C. AU - Tennstedt, S. AU - Palberg, K. AU - Denkert, A. AU - Brandt, W. AU - de Meijere, A. AU - Seliger, B. AU - Wessjohann, L. A. AU - VL - 90 UR - DO - 10.1016/j.ejmech.2014.11.026 AB - The androgen receptor is an important pharmaceutical target for a variety of diseases. This paper presents an in silico/in vitro screening procedure to identify new androgen receptor ligands. The two-step virtual screening procedure uses a three-dimensional pharmacophore model and a docking/scoring routine. About 39,000 filtered compounds were docked with PLANTS and scored by Chemplp. Subsequent to virtual screening, 94 compounds, including 28 steroidal and 66 nonsteroidal compounds, were tested by an androgen receptor fluorescence polarization ligand displacement assay. As a result, 30 compounds were identified that show a relative binding affinity of more than 50% in comparison to 100 nM dihydrotestosterone and were classified as androgen receptor binders. For 11 androgen receptor binders of interest IC50 and Ki values were determined. The compound with the highest affinity exhibits a Ki value of 10.8 nM. Subsequent testing of the 11 compounds in a PC-3 and LNCaP multi readout proliferation assay provides insights into the potential mode of action. Further steroid receptor ligand displacement assays and docking studies on estrogen receptors α and β, glucocorticoid receptor, and progesterone receptor gave information about the specificity of the 11 most active compounds. A2 - C1 - Bioorganic Chemistry ER - TY - JOUR ID - 1066 TI - Correction: Synthesis, cytotoxic and hydrolytic studies of titanium complexes anchored by a tripodal diamine bis(phenolate) ligand JO - Dalton Trans. PY - 2015 SP - 2497-2497 AU - Barroso, S. AU - Coelho, A. M. AU - Gómez-Ruiz, S. AU - Calhorda, M. J. AU - Žižak, ?. AU - Kaluđerović, G. N. AU - Martins, A. M. AU - VL - 44 UR - DO - 10.1039/C4DT90194K AB - Correction for ‘Synthesis, cytotoxic and hydrolytic studies of titanium complexes anchored by a tripodal diamine bis(phenolate) ligand’ by Sónia Barroso et al., Dalton Trans., 2014, 43, 17422–17433. A2 - C1 - Bioorganic Chemistry ER - TY - JOUR ID - 1065 TI - Perfusion Single Photon Emission Computed Tomography in a Mouse Model of Neurofibromatosis Type 1: Towards a Biomarker of Neurologic Deficits JO - J. Cereb. Blood Flow Metab. PY - 2015 SP - 1304-1312 AU - Apostolova, I. AU - Niedzielska, D. AU - Derlin, T. AU - Koziolek, E. J. AU - Amthauer, H. AU - Salmen, B. AU - Pahnke, J. AU - Brenner, W. AU - Mautner, V. F. AU - Buchert, R. AU - VL - 35 UR - DO - 10.1038/jcbfm.2015.43 AB - Neurofibromatosis type 1 (NF1) is a single-gene disorder affecting neurologic function in humans. The NF1+/– mouse model with germline mutation of the NF1 gene presents with deficits in learning, attention, and motor coordination, very similar to NF1 patients. The present study performed brain perfusion single-photon emission computed tomography (SPECT) in NF1+/– mice to identify possible perfusion differences as surrogate marker for altered cerebral activity in NF1. Cerebral perfusion was measured with hexamethyl-propyleneamine oxime (HMPAO) SPECT in NF1+/– mice and their wild-type littermates longitudinally at juvenile age and at young adulthood. Histology and immunohistochemistry were performed to test for structural changes. There was increased HMPAO uptake in NF1 mice in the amygdala at juvenile age, which reduced to normal levels at young adulthood. There was no genotype effect on thalamic HMPAO uptake, which was confirmed by ex vivo measurements of F-18-fluorodeoxyglucose uptake in the thalamus. Morphologic analyses showed no major structural abnormalities. However, there was some evidence of increased density of microglial somata in the amygdala of NF1-deficient mice. In conclusion, there is evidence of increased perfusion and increased density of microglia in juvenile NF1 mice specifically in the amygdala, both of which might be associated with altered synaptic plasticity and, therefore, with cognitive deficits in NF1. A2 - C1 - Bioorganic Chemistry ER - TY - JOUR ID - 1208 TI - Structural studies and cytotoxic activity against human cancer cell lines of mono and dinuclear tin(IV) complexes with the α,α′-dimercapto-o-xylene ligand JO - Inorg. Chim. Acta PY - 2014 SP - 117-122 AU - Gómez-Ruiz, S. AU - Žižak, ?. AU - Kaluđerović, G. N. AU - VL - 423 UR - DO - 10.1016/j.ica.2014.04.023 AB - The reaction of α,α′-dimercapto-o-xylene (H2dmox) with SnPh2Cl2 (1:1) and SnPh3Cl (1:2) in the presence of two equivalents of NEt3 led to the formation of the complexes [SnPh2(dmox)] (1) and [SnPh3(μ-dmox)]2 (2), respectively. Both complexes have been characterized by multinuclear NMR and IR spectroscopy, mass spectrometry and elemental analysis. In addition, the molecular structure of complex 2 has been determined by single crystal X-ray diffraction studies. The cytotoxic activity of 1 and 2 was tested against the tumor cell lines human cervix adenocarcinoma HeLa, breast carcinoma MDA-MB-453, colon carcinoma LS174 and human myelogenous leukemia K562. In addition, the toxicity of both complexes to non-stimulated and stimulated peripheral blood mononuclear cells (PBMC) has been tested. The in vitro cytotoxicity tests show very high antiproliferative activity of both complexes, being much higher that of 2. In addition, this compound shows a higher cytotoxic activity towards cancer cell lines than to non-stimulated and stimulated PBMC, indicating a slight selectivity to cancer cell lines. A2 - C1 - Bioorganic Chemistry ER - TY - JOUR ID - 1237 TI - Synthesis and high in vitro cytotoxicity of some (S,S)-ethylenediamine-N,N’-di-2-propanoate dihydrochloride esters JO - J. Serb. Chem. Soc. PY - 2014 SP - 649-658 AU - Pantelić, N. AU - Zmejkovski, B. B. AU - Stanojković, T. P. AU - Jeftić, V. V. AU - Radić, G. P. AU - Trifunović, S. R. AU - Kaluđerović, G. N. AU - Sabo, T. J. AU - VL - 79 UR - DO - 10.2298/JSC130512022P AB - A novel (S,S)-R2eddip ester, O,O′-diisopentyl-(S,S)-ethylenediamine-N,N′-di-2-propanoate dihydrochloride (1) was synthesized and characterized by IR, 1H- and 13C-NMR spectroscopy, mass spectroscopy and elemental analysis. In vitro antitumor action of 1, and two more R2eddip esters, dialkyl (S,S)-ethylenediamine-N,N′-di-2-propanoate dihydrochlorides, obtained before (alkyl = n-Bu or n-Pe, 2 and 3, respectively), was determined against cervix adenocarcinoma (HeLa), human melanoma (Fem-x), human chronic myelogenous leukemia (K562) cells, and a non-cancerous cell line human embryonic lung fibroblast (MRC-5), using the microculture tetrazolium test MTT assay. Esters 1–3 showed higher cytotoxicity and better selectivity in comparison to cisplatin, used as reference compound. The highest activity was expressed by 1, with IC50(Fem-x) value of 1.51±0.09 μM. A2 - C1 - Bioorganic Chemistry ER - TY - JOUR ID - 1236 TI - Cerebral ABC Transporter-common Mechanisms May Modulate Neurodegenerative Diseases and Depression in Elderly Subjects JO - Arch. Med. Res. PY - 2014 SP - 738-743 AU - Pahnke, J. AU - Fröhlich, C. AU - Paarmann, K. AU - Krohn, M. AU - Bogdanovic, N. AU - Årsland, D. AU - Winblad, B. AU - VL - 45 UR - DO - 10.1016/j.arcmed.2014.10.010 AB - In elderly subjects, depression and dementia often coincide but the actual reason is currently unknown. Does a causal link exist or is it just a reactive effect of the knowledge to suffer from dementia? The ABC transporter superfamily may represent a causal link between these mental disorders. Since the transporters ABCB1 and ABCC1 have been discovered as major β-amyloid-exporting molecules at the blood–brain barrier and ABCC1 was found to be directly activated by St. John's wort (SJW), depression and dementia certainly share an important pathophysiologic link. It was recognized that herbal anti-depressant formulations made from SJW are at least as effective for the treatment of unipolar depression in old age as classical pharmacotherapy, while having fewer side effects (Cochrane reports, 2008). SJW is known to activate various metabolizing and transport systems in the body, with cytochrome P450 enzymes and ABC transporters being most important.Does the treatment of depression in elderly subjects using pharmacological compounds or phytomedical extracts target a mechanism that also accounts for peptide storage in Alzheimer's disease and perhaps other proteopathies of the brain?In this review we summarize recent data that point to a common mechanism and present the first promising causal treatment results of demented elderly subjects with distinct SJW extracts. Insufficient trans-barrier clearance may indeed present a common problem in all the proteopathies of the brain where toxic peptides are deposited in a location-specific manner. Thus, activation of efflux molecules holds promise for future treatment of this large group of devastating disorders. A2 - C1 - Bioorganic Chemistry ER - TY - JOUR ID - 1276 TI - Synthesis, characterization and in vitro antitumor activity of new palladium(II) complexes with (S,S)-R2edda-type esters JO - Polyhedron PY - 2014 SP - 106-111 AU - Zmejkovski, B. B. AU - Savić, A. AU - Poljarević, J. AU - Pantelić, N. AU - Aranđelović, S. AU - Radulović, S. AU - Grgurić-Šipka, S. AU - Kaluđerović, G. N. AU - Sabo, T. J. AU - VL - 80 UR - DO - 10.1016/j.poly.2014.02.026 AB - Six palladium(II) complexes with (S,S)-R2edda-type esters ((S,S)-R2edda-type: (S,S)-eddch = (S,S)-ethylenediamine-N,N′-di-2-(3-cyclohexyl)propanoate, R = Me, Et, n-Pr, 1–3; (S,S)-pddch = (S,S)-propylenediamine-N,N′-di-2-(3-cyclohexyl)propanoate, R = Et, n-Pr, 4, 5; and (S,S)-eddip = (S,S)-ethylenediamne-N,N′-di-2-propanoate, R = i-Am, 6) were synthesized, characterized by IR, NMR spectroscopy, ESI-MS and elemental analysis. DFT calculations indicate that in case of 1–4, the most stable isomers are with (S,S)- and (R,S)-configuration of nitrogen atoms, but for complex 6 (R,R)- and (R,S)-N,N′-configured isomers. Furthermore, complex 5 was obtained as (S,S)-N,N′ configured isomer. Cytotoxicity study was performed against human cervical adenocarcinoma (HeLa), human alveolar basal adenocarcinoma (A549) and non-cancerous human fetal lung fibroblast (MRC-5) cell lines using colorimetric MTT assay. From the investigated palladium(II) complexes 2, 3 and 5 exhibited highest cytotoxic potential against HeLa (IC50: 28.5 ± 3.9, 29.5 ± 1.3 and 34.3 ± 3.2, respectively). A2 - C1 - Bioorganic Chemistry ER - TY - JOUR ID - 1180 TI - Multiple readout assay for hormonal (androgenic and antiandrogenic) and cytotoxic activity of plant and fungal extracts based on differential prostate cancer cell line behavior JO - J. Ethnopharmacol. PY - 2014 SP - 721-730 AU - Bobach, C. AU - Schurwanz, J. AU - Franke, K. AU - Denkert, A. AU - Sung, T. V. AU - Kuster, R. AU - Mutiso, P. C. AU - Seliger, B. AU - Wessjohann, L. A. AU - VL - 155 UR - DO - 10.1016/j.jep.2014.06.008 AB - Ethnopharmacological relevanceProstate cancer is one of the most diagnosed forms of cancer among men in western regions. Many traditional applications or phytotherapeutic concepts propose to inhibit the proliferation of prostate cancer cells. In order to detect influences of plant or fungal extracts and derived fractions on androgen receptor signaling pathways, a differentiating cell proliferation assay was established, which enables the simultaneous detection of hormonal and cytotoxic effects.Material and methodsThe well characterized prostate cancer cell lines LNCaP and PC-3 were used in a multiple readout assay. In all, 186 fractions of 23 traditionally used organisms were screened regarding their effects on proliferation of the two prostate cancer cell lines. The fractions were prepared by accelerated solvent extraction followed by gradient extrography. Extracts of the potential hormonally active plants Cibotium barometz, Heteropterys chrysophylla, and Sideroxylon obtusifolium (= Bumelia sartorum) were phytochemically investigated.ResultsFractions from Cibotium barometz, Cortinarius rubellus, Cyrtomium falcatum, Heteropterys chrysophylla, Nephrolepis exaltata, Salvia miltiorrhiza, Sideroxylon obtusifolium, Trichilia emetica, and Trimeria grandifolia exhibited hormonal influences on prostate cancer cells. Cytotoxic activity towards human cell lines was detected for the first time for fractions from Aglaia spectabilis (A. gigantea), Nephrolepis exaltata and Cortinarius brunneus.ConclusionsThe differential behavior of the two prostate cancer cell lines allows the discrimination between potential androgenic or antiandrogenic activities and effects on the estrogen or glucocorticoid receptor as well as cytotoxic activities. The combined cell lines assay can help to assess the biological activities of material used in traditional medicine. A2 - C1 - Bioorganic Chemistry ER - TY - JOUR ID - 1179 TI - Synthesis, cytotoxic and hydrolytic studies of titanium complexes anchored by a tripodal diamine bis(phenolate) ligand JO - Dalton Trans. PY - 2014 SP - 17422-17433 AU - Barroso, S. AU - Coelho, A. M. AU - Gómez-Ruiz, S. AU - Calhorda, M. J. AU - Žižak, ?. AU - Kaluđerović, G. N. AU - Martins, A. M. AU - VL - 43 UR - DO - 10.1039/C4DT00975D AB - The reactivity, cytotoxic studies and hydrolytic behaviour of diamine bis(phenolate) titanium complexes are reported. The reactions of [Ti(tBu2O2NN′)Cl]2(μ-O) (1) with LiOiPr or HOiPr in the presence of NEt3, aiming at the synthesis of the alkoxido derivative of 1 led to no reaction or to the synthesis of the monomeric complex [Ti(tBu2O2NN′)(OiPr)2] (3), respectively. A small amount of the alkoxidotitanium dimer [Ti(tBu2O2NN′)(OiPr)]2(μ-O) (2) crystallized out of a solution of 3 and DFT calculations showed that the transformation of 1 into 3 is a thermodynamically favorable process in the presence of a base (NEt3) (ΔG = −14.7 kcal mol−1). 2 was quantitatively obtained through the direct reaction of the ligand precursor H2(tBu2O2NN′) with titanium tetra(isopropoxido). Further reaction of 2 with an excess of TMSCl was revealed to be the most suitable method for the preparation of [Ti(tBu2O2NN′)Cl2] (4). 1 and 3 disclosed cytotoxic activity towards HeLa, Fem-x, MDA-MB-361 and K562 cells and 1 exhibited moderate binding affinity to FS-DNA. 1H NMR hydrolysis studies attested the fast decomposition of 4 in the presence of D2O. The hydrolysis of 3 is slower and proceeds through the formation of [Ti(tBu2O2NN′)(OH)]2(μ-O) (5) that was crystallographically characterized. Upon D2O addition 1 immediately forms complex new species, stable in solution for long periods (weeks). A2 - C1 - Bioorganic Chemistry ER - TY - JOUR ID - 1173 TI - Cytotoxic and antiphytofungal activity of the essential oils from two artemisia species JO - World J. Pharm. Res. PY - 2014 SP - 1350-1354 AU - Ali, N. A. A. AU - Wurster, M. AU - Denkert, A. AU - Al-Sokari, S. S. AU - Lindequist, U. AU - Wessjohann, L. AU - VL - 3 UR - https://wjpr.net/dashboard/abstract_id/1210 AB - Hydrodistilled essential oils from aerial parts of Artemisia abyssinica Sch.Bip. ex A. Rich, and Artemisia arborescens L. growing in Yemen were screened for their cytotoxic and antiphytofungal properties as well as their chemical compositions. Twenty-seven components were identified in the essential oils and the main components of these species were found to be davanone (42.34%), camphor (22.88%), nerolidol (8.96%), and chamazulene (4.46%), from A. abyssinica oil and artemisia ketone (51.05%), camphor (14.09%), α-bisabolol (12.56%) and α-phellandrene (8.69%) from A. arborescens. At concentration of 50 and 25 μg/mL, A. arborescens oil showed a strong cytotoxic activity with growth inhibition of 95%(±1.6) and 74%(±3.8) (IC50 of 16.91 μg/mL) against HT29 tumor cells (Human colonic adenocarcinoma cells), while A. abyssinica oil exhibited at concentration of 100 and 50 μg/mL growth inhibition of 71.0% (±12.5) and 27.3%(±14.4) (IC50 of 75.42 μg/mL) respectively. Bioautographic assay was used to evaluate the antiphytofungal activity of the oils against Cladosporium cucumerinum. A2 - C1 - Bioorganic Chemistry ER - TY - JOUR ID - 1189 TI - Organozinn(IV)-beladenes mesoporöses SiO2 als biokompatible Strategie bei der Krebstherapie JO - Angew. Chem. PY - 2014 SP - 6092-6097 AU - Bulatović, M. Z. AU - Maksimović-Ivanić, D. AU - Bensing, C. AU - Gómez-Ruiz, S. AU - Steinborn, D. AU - Schmidt, H. AU - Mojić, M. AU - Korać, A. AU - Golić, I. AU - Pérez-Quintanilla, D. AU - Momčilović, M. AU - Mijatović, S. AU - Kaluđerović, G. N. AU - VL - 126 UR - DO - 10.1002/ange.201400763 AB - Das große therapeutische Potenzial eines Organozinn(IV)‐beladenen nanostrukturierten SiO2 (SBA‐15pSn) wird am Beispiel der Rückbildung eines durch B16‐Zellen induzierten Melanoms bei syngenen C57BL/6‐Mäusen demonstriert. Neben Apoptose als grundlegendem Mechanismus der Antitumorwirkung einer Vielzahl von Chemotherapeutika ist der entscheidende Vorteil dieses mesoporösen zinnhaltigen Materials das Auslösen der Zelldifferenzierung – ein Effekt, der weder für metallbasierte Zytostatika noch für mesoporöse Materialien alleine bisher beobachtet wurde. Dieser nichtaggressive Wirkungsmechanismus ist hochwirksam gegen Tumorzellen aber im gewählten Konzentrationsbereich nichttoxisch für normales Gewebe. JNK‐unabhängige Apoptose (JNK: Jun amino‐terminal kinase), begleitet von der Bildung des melanozytenartigen nichtproliferativen Phänotyps der überlebenden Zellen demonstriert das außergewöhnliche Potenzial von SBA‐15pSn zur Unterdrückung von Tumorwachstum ohne eine unerwünschte kompensatorische Proliferation der erkrankten Zellen als Antwort auf den Zelltod in ihrer Nachbarschaft. A2 - C1 - Bioorganic Chemistry ER - TY - JOUR ID - 1188 TI - Organotin(IV)-Loaded Mesoporous Silica as a Biocompatible Strategy in Cancer Treatment JO - Angew. Chem. Int. Ed. PY - 2014 SP - 5982-5987 AU - Bulatović, M. Z. AU - Maksimović-Ivanić, D. AU - Bensing, C. AU - Gómez-Ruiz, S. AU - Steinborn, D. AU - Schmidt, H. AU - Mojić, M. AU - Korać, A. AU - Golić, I. AU - Pérez-Quintanilla, D. AU - Momčilović, M. AU - Mijatović, S. AU - Kaluđerović, G. N. AU - VL - 53 UR - DO - 10.1002/anie.201400763 AB - The strong therapeutic potential of an organotin(IV) compound loaded in nanostructured silica (SBA‐15pSn) is demonstrated: B16 melanoma tumor growth in syngeneic C57BL/6 mice is almost completely abolished. In contrast to apoptosis as the basic mechanism of the anticancer action of numerous chemotherapeutics, the important advantage of this SBA‐15pSn mesoporous material is the induction of cell differentiation, an effect unknown for metal‐based drugs and nanomaterials alone. This non‐aggressive mode of drug action is highly efficient against cancer cells but is in the concentration range used nontoxic for normal tissue. JNK (Jun‐amino‐terminal kinase)‐independent apoptosis accompanied by the development of the melanocyte‐like nonproliferative phenotype of survived cells indicates the extraordinary potential of SBA‐15pSn to suppress tumor growth without undesirable compensatory proliferation of malignant cells in response to neighboring cell death. A2 - C1 - Bioorganic Chemistry ER - TY - JOUR ID - 1434 TI - Comparison of Impurity Profiles of Lipiblock® vs. Orlistat using HPLC and LC-MS/MS JO - Lat. Am. J. Pharm. PY - 2012 SP - 91-96 AU - Schneider, A. AU - Wessjohann, L. A. AU - Severi, J. A. AU - Wagner, V. AU - VL - 31 UR - http://www.latamjpharm.org/previous_issue.php?vol=31&num=1 AB - Comparative HPLC-UV and LC-MS/MS studies of impurity profiles of a reference sample (Xenical®, F. Hoffmann–La Roche Ltd., Switzerland) vs. generic (Lipiblock®, EMS–Sigma Pharma, a generic drug) were carried out with ethanol extracts of commercial samples. The generic formulation contained higher levels of common impurities as well as a considerable number of impurities not found in the reference product. The detected impurity profile of Lipiblock® revealed that it most likely is based on fermentation. Since the effect of the impurities is unknown, at this point fully synthetic Xenical® appears to offer a better safety margin than Lipiblock® which, however, compares quite well to other generic formulations. A2 - C1 - Bioorganic Chemistry ER - TY - JOUR ID - 1506 TI - Antibacterial and antioxidant activities and acute toxicity of Bumelia sartorum Mart., Sapotaceae, a Brazilian medicinal plant JO - Rev. Bras. Farmacogn. PY - 2011 SP - 86-91 AU - Ruela, H. S. AU - Leal, I. C. R. AU - de Almeida, M. R. A. AU - dos Santos, K. R. N. AU - Wessjohann, L. A. AU - Kuster, R. M. AU - VL - 21 UR - DO - 10.1590/S0102-695X2011005000035 AB - In order to validate the Bumelia sartorum Mart., Sapotaceae, traditional use for infection diseases, this study evaluates the antibacterial activity of the stem bark fractions against methicillin-sensitive (MSSA) and methicillin-resistant (MRSA) Staphylococcus aureus strains by using the agar dilution method and reported as MIC (minimal inhibitory concentration). In addition, the DPPH scavenging activity of these fractions was measured and the chemical composition and acute toxicity of the active fraction were also determined. The ethyl acetate (EtOAc) extract was chemically analyzed by LC/MS, direct ionization APCI/MS, 1H NMR and 13C-NMR. All fractions, except butanol extract, presented high antioxidant activity, especially the methanol and the EtOAc extracts, which showed EC50 values (5.67 and 5.30 µg/mL, respectively) considerably lower than the Gingko-standard EGb 761® (38.58 µg/mL). The antibacterial activity against S. aureus strains was observed in EtOAc (MIC 256-512 µg/mL), which showed a very low toxicity. The chemical study of this fraction revealed the abundant presence of polyphenolic compounds. The antibacterial and antioxidant activities reported in this paper for EtOAc extract from B. sartorum and the low toxicity of this fraction opens the possibility that it could be helpful for the developing of new antibacterial agents for treating S. aureus infections. A2 - C1 - Bioorganic Chemistry ER - TY - JOUR ID - 1504 TI - Characterization of the anticancer properties of monoglycosidic cardenolides isolated from Nerium oleander and Streptocaulon tomentosum JO - J. Ethnopharmacol. PY - 2011 SP - 781-788 AU - Rashan, L. J. AU - Franke, K. AU - Khine, M. M. AU - Kelter, G. AU - Fiebig, H. H. AU - Neumann, J. AU - Wessjohann, L. A. AU - VL - 134 UR - DO - 10.1016/j.jep.2011.01.038 AB - Aim of the studyFor identification of the active constituents we investigated the anticancer activity of cardenolides from Streptocaulon tomentosum Wight & Arn. (Asclepiadaceae) and from Nerium oleander L. (Apocynaceae) which are both used against cancer in the traditional medicine in their region of origin.Material, methods and resultsThe antiproliferative activity of cardenolides isolated from roots of Streptocaulon tomentosum (IC50 < 1–15.3 μM after 2 days in MCF7) and of cardenolide containing fractions from the cold aqueous extract of Nerium oleander leaves (“Breastin”, mean IC50 0.85 μg/ml in a panel of 36 human tumor cell lines), their influence on the cellular viability and on the cell cycle (block at the G2/M-phase or at the S-phase in tumor cells, respectively) were determined using different cell lines. The murine cell line L929 and normal non-tumor cells were not affected. Bioactivity guided fractionation of Breastin resulted in the isolation of the monoglycosidic cardenolides oleandrine, oleandrigeninsarmentoside, neritaloside, odoroside H, and odoroside A (IC50-values between 0.010 and 0.071 μg/ml).ConclusionsThe observed anticancer activities of extracts and isolated cardenolides are in agreement with the ethnomedicinal use of Streptocaulon tomentosum and Nerium oleander. The most active anticancer compounds from both species are monoglycosidic cardenolides possessing the 3β,14β-dihydroxy-5β-card-20(22)-enolide structure with or without an acetoxy group at C-16. The results indicate that the cytotoxic effects are induced by the inhibition of the plasma membrane bound Na+/K+-ATPase. A2 - C1 - Bioorganic Chemistry ER - TY - JOUR ID - 1501 TI - The Multiple Multicomponent Approach to Natural Product Mimics: Tubugis, N-Substituted Anticancer Peptides with Picomolar Activity JO - J. Am. Chem. Soc. PY - 2011 SP - 7692-7695 AU - Pando, O. AU - Stark, S. AU - Denkert, A. AU - Porzel, A. AU - Preusentanz, R. AU - Wessjohann, L. A. AU - VL - 133 UR - DO - 10.1021/ja2022027 AB - The synthesis of a new generation of highly cytotoxic tubulysin analogues (i.e., tubugis) is described. In the key step, the rare, unstable, and synthetically difficult to introduce tertiary amide–N,O-acetal moiety required for high potency in natural tubulysins is replaced by a dipeptoid element formed in an Ugi four-component reaction. Two of the four components required are themselves produced by other multicomponent reactions (MCRs). Thus, the tubugis represent the first examples of the synthesis of natural-product-inspired compounds using three intertwined isonitrile MCRs. A2 - C1 - Bioorganic Chemistry ER - TY - JOUR ID - 1499 TI - Cation–π and π–π stacking interactions allow selective inhibition of butyrylcholinesterase by modified quinine and cinchonidine alkaloids JO - Biochem. Biophys. Res. Commun. PY - 2011 SP - 935-940 AU - Nawaz, S. A. AU - Ayaz, M. AU - Brandt, W. AU - Wessjohann, L. A. AU - Westermann, B. AU - VL - 404 UR - DO - 10.1016/j.bbrc.2010.12.084 AB - Scaffold varied quaternized quinine and cinchonidine alkaloid derivatives were evaluated for their selective butyrylcholinesterase (BChE) inhibitory potential. Ki values were between 0.4–260.5 μM (non-competitive inhibition) while corresponding Kivalues to acetylcholinesterase (AChE) ranged from 7.0–400 μM exhibiting a 250-fold selectivity for BChE.Docking arrangements (GOLD, PLANT) revealed that the extended aromatic moieties and the quaternized nitrogen of the inhibitors were responsible for specific π–π stacking and π–cation interactions with the choline binding site and the peripheral anionic site of BChE’s active site. A2 - C1 - Bioorganic Chemistry ER - TY - JOUR ID - 1480 TI - A Whole-Plant Microtiter Plate Assay for Drought Stress Tolerance-Inducing Effects JO - J. Plant Growth Regul. PY - 2011 SP - 504-511 AU - Geissler, T. AU - Wessjohann, L. A. AU - VL - 30 UR - DO - 10.1007/s00344-011-9212-1 AB - The frequency and intensity of extreme weather events and global temperature are rising, which poses a potential threat to life, specifically crops, and therefore food and bioenergy supply. Reduced water availability has the most severe impact on potential grain yield. Negative effects of transient drought stress (dry spells) can be countered by drought tolerance-inducing chemicals. In search for useful compounds, biochemical assays are fast but limited in scope, whereas whole-plant assays are slow, require large amounts of compounds, and are usually not concentration-related. Here we report the development of a fast, concentration-dependent whole-plant assay using the fast growing duckweed Lemna minor L. 4-Amino-1,8-naphthalimide (1) and the imidacloprid metabolite 6-chloronicotinic acid (2) were affirmed as drought stress tolerance enhancers. Both also reduce oxidative stress-induced cell death in Arabidopsis thaliana (L.) Heynh. cell suspension culture but show differences in their mode of action. A2 - C1 - Bioorganic Chemistry ER - TY - JOUR ID - 1464 TI - Anticholinesterase activity of endemic plant extracts from Soqotra JO - Afr. J. Tradit. Complement. Altern. Med. PY - 2011 SP - 296-299 AU - Bakthir, H. AU - Awadh Ali, N. A. AU - Arnold, N. AU - Teichert, A. AU - Wessjohann, L. AU - VL - 8 UR - DO - 10.4314/ajtcam.v8i3.65292 AB - A total of 30 chloroform and methanol extracts from the following endemic Soqotran plants Acridocarpus socotranus Olive, Boswellia socotranao Balf.fil, Boswellia elongata Balf. fil., Caralluma socotrana N. Br, Cephalocroton socotranus Balf.f, Croton socotranus Balf. fil.., Dendrosicycos socotrana Balf.f., Dorstenia gigas Schweinf. ex Balf. fil., Eureiandra balfourii Cogn. & Balf. fil., Kalanchoe farinaceae Balf.f, Limonium sokotranum (Vierh) Radcl. Sm), Oldenlandia pulvinata, Pulicaria diversifolia( Balf. and Pulicaria stephanocarpa Balf. were screened for their acetylcholinesterase inhibitory activity by using in vitro Ellman method at 50 and 200 μg/ml concentrations. Chloroform extracts of Croton socotranus, Boswellia socotrana, Dorstenia gigas, and Pulicaria stephanocarpa as well as methanol extracts of Eureiandra balfourii exhibited inhibitory activities higher than 50 % at concentration of 200 μg. At a concentrations of 50 μg, the chloroform extract of Croton socotranus exhibited an inhibition of 40.6 %. A2 - C1 - Bioorganic Chemistry ER - TY - JOUR ID - 1548 TI - Breakdown products of neoglucobrassicin inhibit activation of Nrf2 target genes mediated by myrosinase-derived glucoraphanin hydrolysis products JO - Biol. Chem. PY - 2010 SP - 1281-1293 AU - Haack, M. AU - Löwinger, M. AU - Lippmann, D. AU - Kipp, A. AU - Pagnotta, E. AU - Iori, R. AU - Monien, B. H. AU - Glatt, H. AU - Brauer, M. N. AU - Wessjohann, L. A. AU - Brigelius-Flohé, R. AU - VL - 391 UR - DO - 10.1515/bc.2010.134 AB - Glucosinolates (GLSs) present in Brassica vegetables serve as precursors for biologically active metabolites, which are released by myrosinase and induce phase 2 enzymes via the activation of Nrf2. Thus, GLSs are generally considered beneficial. The pattern of GLSs in plants is various, and contents of individual GLSs change with growth phase and culture conditions. Whereas some GLSs, for example, glucoraphanin (GRA), the precursor of sulforaphane (SFN), are intensively studied, functions of others such as the indole GLS neoglucobrassicin (nGBS) are rather unknown as are functions of combinations thereof. We therefore investigated myrosinase-treated GRA, nGBS and synthetic SFN for their ability to induce NAD(P)H:quinone oxidoreductase 1 (NQO1) as typical phase 2 enzyme, and glutathione peroxidase 2 (GPx2) as novel Nrf2 target in HepG2 cells. Breakdown products of nGBS potently inhibit both GRA-mediated stimulation of NQO1 enzyme and Gpx2 promoter activity. Inhibition of promoter activity depends on the presence of an intact xenobiotic responsive element (XRE) and is also observed with benzo[a]pyrene, a typical ligand of the aryl hydrocarbon receptor (AhR), suggesting that suppressive effects of nGBS are mediated via AhR/XRE pathway. Thus, the AhR/XRE pathway can negatively interfere with the Nrf2/ARE pathway which has consequences for dietary recommendations and, therefore, needs further investigation. A2 - C1 - Bioorganic Chemistry ER - TY - JOUR ID - 1547 TI - Acetylcholinesterase inhibitors from the toadstool Cortinarius infractus JO - Bioorg. Med. Chem. PY - 2010 SP - 2173-2177 AU - Geissler, T. AU - Brandt, W. AU - Porzel, A. AU - Schlenzig, D. AU - Kehlen, A. AU - Wessjohann, L. AU - Arnold, N. AU - VL - 18 UR - DO - 10.1016/j.bmc.2010.01.074 AB - Inhibition of acetylcholinesterase (AChE) and therefore prevention of acetylcholine degradation is one of the most accepted therapy opportunities for Alzheimer´s disease (AD), today. Due to lack of selectivity of AChE inhibitor drugs on the market, AD-patients suffer from side effects like nausea or vomiting. In the present study the isolation of two alkaloids, infractopicrin (1) and 10-hydroxy-infractopicrin (2), from Cortinarius infractus Berk. (Cortinariaceae) is presented. Both compounds show AChE-inhibiting activity and possess a higher selectivity than galanthamine. Docking studies show that lacking π–π-interactions in butyrylcholinesterase (BChE) are responsible for selectivity. Studies on other AD pathology related targets show an inhibitory effect of both compounds on self-aggregation of Aβ-peptides but not on AChE induced Aβ-peptide aggregation. Low cytotoxicity as well as calculated pharmacokinetic data suggest that the natural products could be useful candidates for further drug development. A2 - C1 - Bioorganic Chemistry ER - TY - JOUR ID - 1570 TI - Ceanothane and Lupane Type Triterpenes from Zizyphus joazeiro – An Anti-Staphylococcal Evaluation JO - Planta Med. PY - 2010 SP - 47-52 AU - Ramos Leal, I. C. AU - Netto dos Santos, K. R. AU - Itabaiana Júnior, I. AU - Ceva Antunes, O. A. AU - Porzel, A. AU - Wessjohann, L. AU - Machado Kuster, R. AU - VL - 76 UR - DO - 10.1055/s-0029-1185947 AB - The present paper describes the phytochemical and anti-staphylococcal activity investigation of the dichloromethane extract of the Brazilian plant Zizyphus joazeiro Mart. The purification steps were guided by bioassays against 17 bacterial strains of clinical sources, including methicillin-resistant (MRSA) and ‐sensitive (MSSA) Staphylococcus aureus as well as MRSA (ATCC 33591) and MSSA (ATCC 29213) reference strains. One of the more active fractions is comprised of three lupane-type triterpenes, the methylbetulinate (1) as well as the known betulinic (2) and alphitolic (3) acids and, for the first time in the Z. joazeiro, two ceanothane type triterpenes, the methylceanothate (4) and the epigouanic acid A (5). These substances were assayed against one clinical (PVL+) and the reference strains of S. aureus as well as the ATTC 12228 strain of S. epidermidis, in concentrations that varied from 128 to 0.125 µg/mL in order to establish the minimum inhibitory concentration (MIC) of the drugs. The minimum bactericide concentration (MBC) was also evaluated to distinguish the bactericidal from bacteriostatic activity of the crude fractions and single compounds. Compounds 3 and 4 possess the highest antibacterial activity. They inhibit all bacteria tested at 32 µg/mL and 16 µg/mL, respectively, while the other compounds showed no activity at 128 µg/mL. In contrast to single compounds, the triterpenoid fraction showed bactericidal activity at 256 µg/mL. Structural elucidations are based on 1D and 2D NMR spectroscopy as well as HR‐FT‐ICR‐MS experiments. A2 - C1 - Bioorganic Chemistry ER - TY - JOUR ID - 1568 TI - Kleine, ungewöhnliche Peptide gegen Krebs JO - Nachr. Chem. PY - 2010 SP - 526-532 AU - Preusentanz, R. AU - Pando, O. AU - Wessjohann, L. AU - VL - 58 UR - DO - 10.1002/nadc.201069166 AB - N‐alkylierte Peptide wie die Dolastatine und vor allem die jüngeren Tubulysine gelten als vielversprechende Leitsubstanzen für die Krebstherapie. Konjugate der Tubulysine vereinen Tumorselektivität und Aktivität in bisher nicht bekanntem Maß. A2 - C1 - Bioorganic Chemistry ER - TY - JOUR ID - 1625 TI - Neuroprotection and enhanced neurogenesis by extract from the tropical plant Knema laurina after inflammatory damage in living brain tissue JO - J. Neuroimmunol. PY - 2009 SP - 91-99 AU - Häke, I. AU - Schönenberger, S. AU - Neumann, J. AU - Franke, K. AU - Paulsen-Merker, K. AU - Reymann, K. AU - Ismail, G. AU - bin Din, L. AU - Said, I. M. AU - Latiff, A. AU - Wessjohann, L. AU - Zipp, F. AU - Ullrich, O. AU - VL - 206 UR - DO - 10.1016/j.jneuroim.2008.10.007 AB - Inflammatory reactions in the CNS, resulting from a loss of control and involving a network of non-neuronal and neuronal cells, are major contributors to the onset and progress of several major neurodegenerative diseases. Therapeutic strategies should therefore keep or restore the well-controlled and finely-tuned balance of immune reactions, and protect neurons from inflammatory damage. In our study, we selected plants of the Malaysian rain forest by an ethnobotanic survey, and investigated them in cell-based-assay-systems and in living brain tissue cultures in order to identify anti-inflammatory and neuroprotective effects. We found that alcoholic extracts from the tropical plant Knema laurina (Black wild nutmeg) exhibited highly anti-inflammatory and neuroprotective effects in cell culture experiments, reduced NO- and IL-6-release from activated microglia cells dose-dependently, and protected living brain tissue from microglia-mediated inflammatory damage at a concentration of 30 µg/ml. On the intracellular level, the extract inhibited ERK-1/2-phosphorylation, IkB-phosphorylation and subsequently NF-kB-translocation in microglia cells. K. laurina belongs to the family of Myristicaceae, which have been used for centuries for treatment of digestive and inflammatory diseases and is also a major food plant of the Giant Hornbill. Moreover, extract from K. laurina promotes also neurogenesis in living brain tissue after oxygen–glucose deprivation. In conclusion, extract from K. laurina not only controls and limits inflammatory reaction after primary neuronal damage, it promotes moreover neurogenesis if given hours until days after stroke-like injury. A2 - C1 - Bioorganic Chemistry ER - TY - JOUR ID - 1617 TI - Antioomycete Activity of γ-Oxocrotonate Fatty Acids against P. infestans JO - J. Agr. Food Chem. PY - 2009 SP - 9607-9612 AU - Eschen-Lippold, L. AU - Draeger, T. AU - Teichert, A. AU - Wessjohann, L. AU - Westermann, B. AU - Rosahl, S. AU - Arnold, N. AU - VL - 57 UR - DO - 10.1021/jf902067k AB - Infections with Phytophthora infestans, the causal agent of potato and tomato late blight disease, are difficult to control and can lead to considerable agricultural losses. Thus, the development of new effective agents against the pathogen is of great interest. In previous work, (E)-4-oxohexadec-2-enoic acid (3) was isolated from Hygrophorus eburneus, which exhibited fungicidal activity against Cladosporium cucumerinum. Here, the inhibitory effect of 3 on P. infestans spore germination and mycelium growth in vitro is demonstrated. The in vivo effect on infections of whole potato plants was investigated by spraying plants with the sodium salt of 3, sodium (2E)-4-oxohexadec-2-enoic acid (4), prior to P. infestans inoculation. Additionally, the influence of 3 on mycelium growth of Colletotrichum coccodes, the causal agent of potato black dot disease, was analyzed. In all approaches, a significant inhibition of pathogen development was achieved. Importantly, the unsaturated fatty acid exerted no toxic effect when sprayed on plants, a prerequisite for its commercial use. A2 - C1 - Bioorganic Chemistry; Biochemistry of Plant Interactions ER - TY - JOUR ID - 1652 TI - Multicomponent reactions for the synthesis of multifunctional agents with activity against cancer cells JO - Chem. Commun. PY - 2009 SP - 4702 AU - Shabaan, S. AU - Ba, L. A. AU - Abbas, M. AU - Burkholz, T. AU - Denkert, A. AU - Gohr, A. AU - Wessjohann, L. A. AU - Sasse, F. AU - Weber, W. AU - Jacob, C. AU - VL - UR - DO - 10.1039/B823149D AB - Multicomponent Passerini and Ugi reactions enable the fast and efficient synthesis of redox-active multifunctional selenium and tellurium compounds, of which some show considerable cytotoxicity against specific cancer cells. A2 - C1 - Bioorganic Chemistry ER - TY - JOUR ID - 1633 TI - Anti-fungal flavonoids from Tibouchina grandifolia JO - Biochem. Syst. Ecol. PY - 2009 SP - 63-65 AU - Kuster, R. M. AU - Arnold, N. AU - Wessjohann, L. AU - VL - 37 UR - DO - 10.1016/j.bse.2009.01.005 AB - A2 - C1 - Bioorganic Chemistry ER - TY - JOUR ID - 1631 TI - Expression, regulation and function of the ISGylation system in prostate cancer JO - Oncogene PY - 2009 SP - 2606-2620 AU - Kiessling, A. AU - Hogrefe, C. AU - Erb, S. AU - Bobach, C. AU - Fuessel, S. AU - Wessjohann, L. AU - Seliger, B. AU - VL - 28 UR - DO - 10.1038/onc.2009.115 AB - The androgen receptor (AR) plays a crucial role in the modulation of prostate cell proliferation and is involved in the development and progression of prostate cancer (PCa). An understanding of the complex regulation of AR provides novel treatment options for PCa. Here, we show (i) that the ubiquitin-like modifier, interferon-stimulated gene 15 (ISG15), and most enzymes involved in ISG15 conjugation were upregulated in tumor samples versus in non-malignant tissues of PCa patients and (ii) that the expression of these components significantly differed between tumors in patients treated with and without androgen ablation. Using PCa cell lines as in vitro models, the specific androgen-mediated, AR-dependent regulation of the ISGylation components was confirmed. In addition, the ISGylation system controls AR mRNA and protein expressions, as overexpression of Ube1L as a limiting ISGylation factor in the AR+ androgen-sensitive PCa cell line, LNCaP, results in significant AR upregulation, accompanied by an increased proliferation even under androgen deprivation. Accordingly, Ube1L knockdown decreased the AR expression. Thus, this study describes for the first time the modulation of AR expression by ISGylation components, which affects the proliferation of PCa cells, thereby providing evidence for a novel function of the ISGylation system in malignant transformation. A2 - C1 - Bioorganic Chemistry ER - TY - JOUR ID - 1881 TI - Analysis of fungal cyclopentenone derivatives from Hygrophorus spp. by liquid chromatography/electrospray-tandem mass spectrometry JO - J. Mass Spectrom. PY - 2006 SP - 361-371 AU - Lübken, T. AU - Arnold, N. AU - Wessjohann, L. AU - Böttcher, C. AU - Schmidt, J. AU - VL - 41 UR - DO - 10.1002/jms.996 AB - Fruitbodies of the genus Hygrophorus (Basidiomycetes) contain a series of anti‐biologically active compounds. These substances named hygrophorones possess a cyclopentenone skeleton. LC/ESI‐MS/MS presents a valuable tool for the identification of such compounds. The mass spectral behaviour of typical selected members of this group under positive and negative ion electrospray conditions is discussed. Using the ESI collision‐induced dissociation (CID) mass spectra of the [M + H]+ and [M − H]− ions, respectively, the compounds can be classified with respect to the substitution pattern at the cyclopentenone ring and the type of oxygenation at C‐6 (hydroxy/acetoxy or oxo function) of the side chain. The elemental composition of the fragment ions was determined by ESI‐QqTOF measurements. Thus, in case of the negative ion CID mass spectra an unusual loss of CO2 from the deprotonated molecular ions could be observed. A2 - C1 - Bioorganic Chemistry ER - TY - JOUR ID - 1947 TI - Epothilone D affects cell cycle and microtubular pattern in plant cells JO - J. Exp. Bot. PY - 2005 SP - 2131-2137 AU - Hause, G. AU - Lischewski, S. AU - Wessjohann, L. A. AU - Hause, B. AU - VL - 56 UR - DO - 10.1093/jxb/eri211 AB - Epothilones, macrocyclic lactones from culture filtrates of the myxobacterium Sorangium cellulosum, are known as taxol-like microtubular drugs in human medicine. To date, nothing is known about the effect of epothilones on microtubules (MTs) in plant cells and/or on the plant cell cycle. As shown in this report, the treatment of tomato cell suspension cultures with epothilone D produced a continuous increase in the mitotic index. Dose–response curves revealed that epothilone D alters the mitotic index at concentrations as low as 1.5 μM. Mitotic arrest was already visible after only 2 h of treatment, and 55% of the cells were arrested after 24 h. As shown by immunocytological methods, abnormal spindles are formed during metaphase, which leads to a random distribution of chromosomes in the whole cell and prevents the formation of a metaphase plate. The process of chromosome decondensation does not seem to be affected, because micronuclei form at the same place with the distributed chromosomes. This suggests that epothilone D influences the stability of plant MTs mainly during metaphase of the mitotic cycle. In metaphase, the effects of epothilone D seem to be irreversible, because cells with an abnormal spindle could not be recovered after removal of the drug. A2 - C1 - Cell and Metabolic Biology; Bioorganic Chemistry ER - TY - JOUR ID - 1985 TI - Unusual Bioactive 4-Oxo-2-alkenoic Fatty Acids from Hygrophorus eburneus JO - Z. Naturforsch. B PY - 2005 SP - 25-32 AU - Teichert, A. AU - Lübken, T. AU - Schmidt, J. AU - Porzel, A. AU - Arnold, N. AU - Wessjohann, L. AU - VL - 60 UR - DO - 10.1515/znb-2005-0105 AB - From fruit bodies of the basidiomycete Hygrophorus eburneus (Bull.: Fr.) Fr. (Tricholomataceae) eight fatty acids (C16, C18) with γ -oxocrotonate partial structure could be isolated. Initial tests demonstrate their bactericidal and fungicidal activity. The structures of (2E,9E)-4-oxooctadeca- 2,9,17-trienoic acid (1), (2E,11Z)-4-oxooctadeca-2,11,17-trienoic acid (2), (E)-4-oxohexadeca-2,15- dienoic acid (3), (E)-4-oxooctadeca-2,17-dienoic acid (4), (2E,9E)-4-oxooctadeca-2,9-dienoic acid (5), (2E,11Z)-4-oxooctadeca-2,11-dienoic acid (6), (E)-4-oxohexadec-2-enoic acid (7), and (E)-4- oxooctadec-2-enoic acid (8) were elucidated on the basis of their spectroscopic data. A2 - C1 - Bioorganic Chemistry ER - TY - JOUR ID - 1984 TI - Bioaktive Sekundärmetaboliten aus der Gattung Hygrophorus (Basidiomycetes) JO - Z. Mykol. PY - 2005 SP - 53-61 AU - Teichert, A. AU - Lübken, T. AU - Kummer, M. AU - Besl, H. AU - Haslberger, H. AU - Arnold, N. AU - VL - 71 UR - https://www.dgfm-ev.de/publikationen/bioaktive-sekundaermetaboliten-aus-der-gattung-hygrophorus-basidiomycetes AB - Die fungizide Wirkung von verschiedenen Rohextrakten von 23 Arten der Gattung Hygrophorus gegen Cladosporium cucumerinum wird gezeigt. Als Wirkprinzip konnten ungewöhnliche Fettsäuren und die Hygrophorone A-G identifiziert werden. A2 - C1 - Bioorganic Chemistry ER - TY - JOUR ID - 2025 TI - Hygrophorones A–G: fungicidal cyclopentenones from Hygrophorus species (Basidiomycetes) JO - Phytochemistry PY - 2004 SP - 1061-1071 AU - Lübken, T. AU - Schmidt, J. AU - Porzel, A. AU - Arnold, N. AU - Wessjohann, L. AU - VL - 65 UR - DO - 10.1016/j.phytochem.2004.01.023 AB - Twenty new 5-(hydroxyalkyl)-2-cyclopentenone derivatives (hygrophorones) could be isolated from Hygrophorus latitabundus, H. olivaceoalbus, H. persoonii, and H. pustulatus. Their fungicidal activity was exemplarily tested. The hygrophorones have structural similarities to the antibiotic pentenomycin. Chemically, hygrophorones are 2-cyclopentenones with hydroxy or acetoxy substituents at C-4 and/or C-5. An odd-numbered 1′ oxidized alkyl chain (C11, C13, C15, or C17) is attached at C-5. In addition, from H. persoonii the new γ-butyrolactone derivative [5-(E)-2-hydroxytetradexylidene-5H-furan-2-one] could be isolated. Some hygrophorones are responsible for the color reaction of the stipes of these fungi upon treatment with potassium hydroxide solution. Structural elucidations are based on 1D (1H, 13C) and 2D (COSY, NOESY, HSQC, HMBC) NMR spectroscopic analyses as well as HR-FT-ICR-MS investigations.A series of new cyclopentenone derivatives and butyrolactones with antifungical activity could be isolated from fruit bodies of the basidiomyceteous genus Hygrophorus. Structural elucidations are based on 1D and 2D NMR spectroscopic analyses as well as HR-FT-ICR-MS investigations. A2 - C1 - Bioorganic Chemistry ER -