Unser 10. Leibniz Plant Biochemistry Symposium am 7. und 8. Mai war ein großer Erfolg. Thematisch ging es in diesem Jahr um neue Methoden und Forschungsansätze der Naturstoffchemie. Die exzellenten Vorträge über Wirkstoffe…
Omanische Heilpflanze im Fokus der Phytochemie IPB-Wissenschaftler und Partner aus Dhofar haben jüngst die omanische Heilpflanze Terminalia dhofarica unter die phytochemische Lupe genommen. Die Pflanze ist reich an…
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…
Corrêa dos Santos, C. H.; Geraldo de Carvalho, M.; Laub, A.; Franke, K.; Wessjohann, L.;UHPLC-ESI-Orbitrap-HR-MS analysis of cyclopeptide alkaloids from Ziziphus joazeiroNat. Prod. Commun.161-13(2021)DOI: 10.1177/1934578x211054955
Ziziphus joazeiro Mart., popularly known as “juazeiro”, is a tree widely found in the northeast of Brazil. It is commonly used as an anti-inflammatory, antibacterial, antifungal, and analgesic agent. The stem extract exhibited, beside cytotoxic properties, substantial activity against the Gram-negative bacterium Allivibrio fischeri. UHPLC-ESI-Orbitrap-HR-MS analysis of the alkaloidal fraction of the crude methanolic stem extract of this species enabled the detection and putative identification of sixteen cyclopeptide alkaloids (CPAs), including four possibly new structures. According to the MS2 fragmentation analysis, from the sixteen identified CPAs, three possess a type-Ia1, one a type-Ia2, and twelve a type-Ib cyclopeptide alkaloid core. The structures of paliurine-C and -D were supported by NMR data.
Publikation
Serra, P.; Carbonell, A.; Navarro, B.; Gago-Zachert, S.; Li, S.; Di Serio, F.; Flores, R.;Symptomatic plant viroid infections in phytopathogenic fungi: A request for a critical reassessmentProc. Natl. Acad. Sci. U.S.A.11710126-10128(2020)DOI: 10.1073/pnas.1922249117
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.
Publikation
Wijnker, E.; Harashima, H.; Müller, K.; Parra-Nuñez, P.; de Snoo, C. B.; van de Belt, J.; Rajjou, L.; Bayer, M.; Pradillo, M.; Schnittger, A.;The Cdk1/Cdk2 homolog CDKA;1 controls the recombination landscape in ArabidopsisProc. Natl. Acad. Sci. U.S.A.11612534-12539(2019)DOI: 10.1073/pnas.1820753116
Little is known how patterns of cross-over (CO) numbers and distribution during meiosis are established. Here, we reveal that cyclin-dependent kinase A;1 (CDKA;1), the homolog of human Cdk1 and Cdk2, is a major regulator of meiotic recombination in Arabidopsis. Arabidopsis plants with reduced CDKA;1 activity experienced a decrease of class I COs, especially lowering recombination rates in centromere-proximal regions. Interestingly, this reduction of type I CO did not affect CO assurance, a mechanism by which each chromosome receives at least one CO, resulting in all chromosomes exhibiting similar genetic lengths in weak loss-of-function cdka;1 mutants. Conversely, an increase of CDKA;1 activity resulted in elevated recombination frequencies. Thus, modulation of CDKA;1 kinase activity affects the number and placement of COs along the chromosome axis in a dose-dependent manner.