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Publikationen - Natur- und Wirkstoffchemie

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Publikation

Rodríguez-Núñez, K.; Cortés-Monroy, A.; Serey, M.; Ensari, Y.; Davari, M. D.; Bernal, C.; Martinez, R.; Modulating substrate specificity of Rhizobium sp. Histamine Dehydrogenase through protein engineering for food quality applications Molecules 28, 3748, (2023) DOI: 10.3390/molecules28093748

Histamine is a biogenic amine found in fish-derived and fermented food products with physiological relevance since its concentration is proportional to food spoilage and health risk for sensitive consumers. There are various analytical methods for histamine quantification from food samples; however, a simple and quick enzymatic detection and quantification method is highly desirable. Histamine dehydrogenase (HDH) is a candidate for enzymatic histamine detection; however, other biogenic amines can change its activity or produce false positive results with an observed substrate inhibition at higher concentrations. In this work, we studied the effect of site saturation mutagenesis in Rhizobium sp. Histamine Dehydrogenase (Rsp HDH) in nine amino acid positions selected through structural alignment analysis, substrate docking, and proximity to the proposed histamine-binding site. The resulting libraries were screened for histamine and agmatine activity. Variants from two libraries (positions 72 and 110) showed improved histamine/agmatine activity ratio, decreased substrate inhibition, and maintained thermal resistance. In addition, activity characterization of the identified Phe72Thr and Asn110Val HDH variants showed a clear substrate inhibition curve for histamine and modified kinetic parameters. The observed maximum velocity (Vmax) increased for variant Phe72Thr at the cost of an increased value for the Michaelis–Menten constant (Km) for histamine. The increased Km value, decreased substrate inhibition, and biogenic amine interference observed for variant Phe72Thr support a tradeoff between substrate affinity and substrate inhibition in the catalytic mechanism of HDHs. Considering this tradeoff for future enzyme engineering of HDH could lead to breakthroughs in performance increases and understanding of this enzyme class.
Publikation

Rodriguez, A.; Martell-Huguet, E. M.; González-García, M.; Alpízar-Pedraza, D.; Alba, A.; Vazquez, A. A.; Grieshober, M.; Spellerberg, B.; Stenger, S.; Münch, J.; Kissmann, A.-K.; Rosenau, F.; Wessjohann, L. A.; Wiese, S.; Ständker, L.; Otero-González, A. J.; Identification and characterization of three new antimicrobial peptides from the marine mollusk Nerita versicolor (Gmelin, 1791) Int. J. Mol. Sci. 24, 3852, (2023) DOI: 10.3390/ijms24043852

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.
Publikation

Ihlenburg, R. B. J.; Petracek, D.; Schrank, P.; Davari, M. D.; Taubert, A.; Rothenstein, D.; Identification of the first sulfobetaine hydrogel‐binding peptides via phage display assay Macromolecular Rapid Communications 44, 2200896, (2023) DOI: 10.1002/marc.202200896

Using the M13 phage display, a series of 7- and 12-mer peptides which interact with new sulfobetaine hydrogels are identified. Two peptides each from the 7- and 12-mer peptide libraries bind to the new sulfobetaine hydrogels with high affinity compared to the wild-type phage lacking a dedicated hydrogel binding peptide. This is the first report of peptides binding to zwitterionic sulfobetaine hydrogels and the study therefore opens up the pathway toward new phage or peptide/hydrogel hybrids with high application potential.
Publikation

Hussain, H.; Xiao, J.; Ali, A.; Green, I. R.; Westermann, B.; Unusually cyclized triterpenoids: occurrence, biosynthesis and chemical synthesis Nat. Prod. Rep. 40, 412-451, (2023) DOI: 10.1039/d2np00033d

Covering: 2009 to 2021Biosynthetically, most of the syntheses of triterpenes follow the cascade cyclization and rearrangement of the acyclic precursors viz., squalene (S) and 2,3-oxidosqualene (OS), which lead to the very well known tetra- and pentacyclic triterpene skeletons. Aside from these, numerous other triterpenoid molecules are also reported from various natural sources and their structures are derived from \"S\" and \"OS\" via some unusual cyclization operations which are different from the usual tetra- and pentacyclic frameworks. Numerous compelling advances have been made and reported in the identification of these unusual cyclized mono-, di-, tri- and tetracyclic triterpenes between 2009 and 2021. Besides a dramatic increase in the newly isolated uncommon cyclized triterpenoids, substantial progress in the (bio)-synthesis of these triterpenes has been published along with significant progress in their biological effects. In this review, 180 new unusual cyclized triterpenoids together with their demonstrated biogenetic pathways, syntheses and biological effects will be categorized and discussed.
Publikation

Hussain, H.; Siddiqui, H.; Gerothanassis, I. P.; Prof. Dr. M. Iqbal Choudhary-A lifetime career dedicated to remarkable services in “natural products sciences” Frontiers in Pharmacology 14, 1119419, (2023) DOI: 10.3389/fphar.2023.1119419

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Publikation

Hussain, A.; Attique, F.; Naqvi, S. A. R.; Ali, A.; Ibrahim, M.; Hussain, H.; Zafar, F.; Iqbal, R. S.; Ayub, M. A.; Assiri, M. A.; Imran, M.; Ullah, S.; Nanoformulation of Curcuma longa root extract and evaluation of its dissolution potential ACS Omega 8, 1088-1096, (2023) DOI: 10.1021/acsomega.2c06258

Medicinal plants have been widely used for therapeutic purposes for a long time, but they have been found to have some major issues such as low water solubility and bioavailability. In the present study, the nanoformulation of Curcuma longa L. plant extract was prepared to enhance its dissolution potential and biological activities. For the formulation of the nanosuspension, an ethanolic extract of C. longa was prepared through Soxhlet extraction using the nanoformulation technique. The nanosuspensions were formulated using four different stabilizers, namely sodium lauryl sulfate (SLS), hydroxy propyl methyl cellulose (HPMC), poly(vinyl alcohol) (PVA), and polysorbate-80 (P-80). The scanning electron microscopy (SEM), polydispersity index, and ζ potential were used for characterization of the nanoformulation. Among all of these, the surfactant stabilizer SLS was found to be the best. The average particle size of the selected optimized nanosuspension was found to be 308.2 nm with a polydispersity index (PDI) value of 0.330. The ζ potential value of the optimized nanosuspension was recorded at −33.3 mV. The SEM image indicated that the particles were slightly agglomerated, which may have occurred during lyophilization of the nanosuspension. The highest dissolution rate recorded at pH = 7 was 192.32 μg/mL, which indicates pH = 7 as the most appropriate condition for the dissolution of the C. longa nanosuspension. The antioxidant, antimicrobial, and antifungal activities of the optimized nanosuspension were also determined with regard to the coarse plant extract. The study findings suggested that the nanoprecipitation approach helps in enhancing the dissolution potential and biological activities of C. longa root extract.
Publikation

Hussain, A.; Bourguet-Kondracki, M.-L.; Majeed, M.; Ibrahim, M.; Imran, M.; Yang, X.-W.; Ahmed, I.; Altaf, A. A.; Khalil, A. A.; Rauf, A.; Wilairatana, P.; Hemeg, H. A.; Ullah, R.; Green, I. R.; Ali, I.; Shah, S. T. A.; Hussain, H.; Marine life as a source for breast cancer treatment: A comprehensive review Biomedicine & Pharmacotherapy 159, 114165, (2023) DOI: 10.1016/j.biopha.2022.114165

Breast cancer, one of the most significant tumors among all cancer cells, still has deficiencies for effective treatment. Moreover, substitute treatments employing natural products as bioactive metabolites has been seriously considered. The source of bioactive metabolites are not only the most numerous but also represent the richest source. A unique source is from the oceans or marine species which demonstrated intriguing chemical and biological diversity which represents an astonishing reserve for discovering novel anticancer drugs. Notably, marine sponges produce the largest amount of diverse bioactive peptides, alkaloids, terpenoids, polyketides along with many secondary metabolites whose potential is mostly therapeutic. In this review, our main focus is on the marine derived secondary metabolites which demonstrated cytotoxic effects towards numerous breast cancer cells and have been isolated from the marine sources such as marine sponges, cyanobacteria, fungi, algae, tunicates, actinomycetes, ascidians, and other sources of marine organisms.
Publikation

Hussain, H.; Editorial for special issue “Natural products as potential source of antidiabetic compounds” Current Issues in Molecular Biology 45, 2699-2702, (2023) DOI: 10.3390/cimb45040176

Natural products (NPs) are characterized by possessing intriguing scaffold diversity along with structural complexity and have been a comprehensive source of lead compounds for drug discovery [...]
Publikation

Herrera-Rocha, F.; Fernández-Niño, M.; Cala, M. P.; Duitama, J.; Barrios, A. F. G.; Omics approaches to understand cocoa processing and chocolate flavor development: A review Food Res. Int. 165, 112555, (2023) DOI: 10.1016/j.foodres.2023.112555

The global market of chocolate has increased worldwide during the last decade and is expected to reach a value of USD 200 billion by 2028. Chocolate is obtained from different varieties of Theobroma cacao L, a plant domesticated more than 4000 years ago in the Amazon rainforest. However, chocolate production is a complex process requiring extensive post-harvesting, mainly involving cocoa bean fermentation, drying, and roasting. These steps have a critical impact on chocolate quality. Standardizing and better understanding cocoa processing is, therefore, a current challenge to boost the global production of high-quality cocoa worldwide. This knowledge can also help cocoa producers improve cocoa processing management and obtain a better chocolate. Several recent studies have been conducted to dissect cocoa processing via omics analysis. A vast amount of data has been produced regarding omics studies of cocoa processing performed worldwide. This review systematically analyzes the current data on cocoa omics using data mining techniques and discusses opportunities and gaps for cocoa processing standardization from this data. First, we observed a recurrent report in metagenomics studies of species of the fungi genus Candida and Pichia as well as bacteria from the genus Lactobacillus, Acetobacter, and Bacillus. Second, our analyzes of the available metabolomics data showed clear differences in the identified metabolites in cocoa and chocolate from different geographical origin, cocoa type, and processing stage. Finally, our analysis of peptidomics data revealed characteristic patterns in the gathered data including higher diversity and lower size distribution of peptides in fine-flavor cocoa. In addition, we discuss the current challenges in cocoa omics research. More research is still required to fill gaps in central matter in chocolate production as starter cultures for cocoa fermentation, flavor evolution of cocoa, and the role of peptides in the development of specific flavor notes. We also offer the most comprehensive collection of multi-omics data in cocoa processing gathered from different research articles.Graphical abstract
  • Die Leibniz-Gemeinschaft
  • Digitalisierung in der Landwirtschaft
  • Martin-Luther Universität Halle
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