Geschmack ist vorhersagbar: Mit FlavorMiner. FlavorMiner heißt das Tool, das IPB-Chemiker und Partner aus Kolumbien jüngst entwickelt haben. Das Programm kann, basierend auf maschinellem Lernen (KI), anhand der…
Seit Februar 2021 bietet Wolfgang Brandt, ehemaliger Leiter der Arbeitsgruppe Computerchemie am IPB, sein Citizen Science-Projekt zur Pilzbestimmung an. Dafür hat er in regelmäßigen Abständen öffentliche Vorträge zur Vielfalt…
Mpetga, J. D. S.; Nago, R. D. T.; Tamokou, J.-D.-D.; Fobofou, S. A. T.; Bitchagno, G. T. M.; Wessjohann, L. A.; Tene, M.; Ngouela, A. S.;A new ceramide from Cissus aralioides Baker (Vitaceae) and its antimicrobial activityChem. Biodivers.19e202200678(2022)DOI: 10.1002/cbdv.202200678
Purification through repeated column chromatography over silica gel and Sephadex LH-20 of the ethanol extract of the stems of Cissus aralioides (Baker) Planch. resulted in the isolation of a new ceramide, aralioidamide A (1) along with five known compounds (2-6). Their structures were determined by the extensive analysis of their spectroscopic (1D and 2D NMR) and spectrometric data, and comparison with those reported in the literature. Aralioidamide A (1) displayed weak antibacterial activity (MIC = 256 μg/mL) against Bacillus subtilis, Staphylococcus aureus and Shigella flexneri and was inactive (MIC > 256 μg/mL) against the tested fungi.
Publikation
Zanatta, N.; Mittersteiner, M.; Aquino, E. C.; Budragchaa, T.; Wessjohann, L. A.; Bonacorso, H. G.; Martins, M. A. P.;Synthesis of methylene-bridged trifluoromethyl azoles using 5-(1,2,3-Triazol-1-yl)enonesSynthesis54439-450(2022)DOI: 10.1055/s-0040-1719837
A protocol for synthesizing triazole-containing pyrazolines and pyrazoles selectively using trifluoromethylated 5-(1,2,3-triazol-1-yl)enones as starting materials, is reported. The selectivity of the reaction was controlled by the nature of the hydrazine or derivative used: free hydrazines furnished the 1,5-regiosiomer exclusively in yields up to 98%, whereas protected hydrazines provided the 1,3-regioisomer in yields up to 77%. To demonstrate the synthetic versatility of the triazole-based enone, reactions with other unsymmetrical dinucleophiles (hydroxylamine hydrochloride and S-methyl isothiourea sulfates) allowed the selective preparation of triazole-containing isoxazoline and pyrimidine rings.
Publikation
Trempel, F.; Eschen‐Lippold, L.; Bauer, N.; Ranf, S.; Westphal, L.; Scheel, D.; Lee, J.;A mutation in Asparagine‐Linked Glycosylation 12 (ALG12) leads to receptor misglycosylation and attenuated responses to multiple microbial elicitorsFEBS Lett.5942440-2451(2020)DOI: 10.1002/1873-3468.13850
Changes in cellular calcium levels are one of the earliest signalling events in plants exposed to pathogens or other exogenous factors. In a genetic screen, we identified an Arabidopsis thaliana ‘changed calcium elevation 1 ’ (cce1 ) mutant with attenuated calcium response to the bacterial flagellin flg22 peptide and several other elicitors. Whole genome re‐sequencing revealed a mutation in ALG12 (Asparagine‐Linked Glycosylation 12 ) that encodes the mannosyltransferase responsible for adding the eighth mannose residue in an α‐1,6 linkage to the dolichol‐PP‐oligosaccharide N ‐glycosylation glycan tree precursors. While properly targeted to the plasma membrane, misglycosylation of several receptors in the cce1 background suggests that N ‐glycosylation is required for proper functioning of client proteins.
Publikation
Farag, M. A.; Al-Mahdy, D. A.; Salah El Dine, R.; Fahmy, S.; Yassin, A.; Porzel, A.; Brandt, W.;Structure-Activity Relationships of Antimicrobial Gallic Acid Derivatives from Pomegranate and Acacia Fruit Extracts against Potato Bacterial Wilt PathogenChem. Biodivers.12955-962(2015)DOI: 10.1002/cbdv.201400194
Bacterial wilts of potato, tomato, pepper, and or eggplant caused by Ralstonia solanacearum are among the most serious plant diseases worldwide. In this study, the issue of developing bactericidal agents from natural sources against R. solanacearum derived from plant extracts was addressed. Extracts prepared from 25 plant species with antiseptic relevance in Egyptian folk medicine were screened for their antimicrobial properties against the potato pathogen R. solancearum by using the disc‐zone inhibition assay and microtitre plate dilution method. Plants exhibiting notable antimicrobial activities against the tested pathogen include extracts from Acacia arabica and Punica granatum. Bioactivity‐guided fractionation of A. arabica and P. granatum resulted in the isolation of bioactive compounds 3,5‐dihydroxy‐4‐methoxybenzoic acid and gallic acid, in addition to epicatechin. All isolates displayed significant antimicrobial activities against R. solanacearum (MIC values 0.5–9 mg/ml), with 3,5‐dihydroxy‐4‐methoxybenzoic acid being the most effective one with a MIC value of 0.47 mg/ml. We further performed a structure–activity relationship (SAR) study for the inhibition of R. solanacearum growth by ten natural, structurally related benzoic acids.