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…
Dahiya, P.; Bürstenbinder, K.;The making of a ring: Assembly and regulation of microtubule-associated proteins during preprophase band formation and division plane set-upCurr. Opin. Plant Biol.73102366(2023)DOI: 10.1016/j.pbi.2023.102366
The preprophase band (PPB) is a transient cytokinetic structure that marks the future division plane at the onset of mitosis. The PPB forms a dense cortical ring of mainly microtubules, actin filaments, endoplasmic reticulum, and associated proteins that encircles the nucleus of mitotic cells. After PPB disassembly, the positional information is preserved by the cortical division zone (CDZ). The formation of the PPB and its contribution to timely CDZ set-up involves activities of functionally distinct microtubule-associated proteins (MAPs) that interact physically and genetically to support robust division plane orientation in plants. Recent studies identified two types of plant-specific MAPs as key regulators of PPB formation, the TON1 RECRUITMENT MOTIF (TRM) and IQ67 DOMAIN (IQD) families. Both families share hallmarks of disordered scaffold proteins. Interactions of IQDs and TRMs with multiple binding partners, including the microtubule severing KATANIN1, may provide a molecular framework to coordinate PPB formation, maturation, and disassembly.
Publikation
Brand, A.; Tissier, A.;Control of resource allocation between primary and specialized metabolism in glandular trichomesCurr. Opin. Plant Biol.66102172(2022)DOI: 10.1016/j.pbi.2022.102172
Plant specialized metabolites are often synthesized and stored in dedicated morphological structures such as glandular trichomes, resin ducts, or laticifers where they accumulate in large concentrations. How this high productivity is achieved is still elusive, in particular, with respect to the interface between primary and specialized metabolism. Here, we focus on glandular trichomes to survey recent progress in understanding how plant metabolic cell factories manage to balance homeostasis of essential central metabolites while producing large quantities of compounds that constitute a metabolic sink. In particular, we review the role of gene duplications, transcription factors and photosynthesis.
Publikation
Moura, P. H. B.; Porzel, A.; Nunes, R. M.; Baratto, L. C.; Wessjohann, L. A.; Martins, R. C. C.; Leal, I. C. R.;Antioxidant capacity and fragmentation features of
C‐glycoside isoflavones by high‐resolution electrospray ionization tandem mass spectrometry using collision‐induced and high‐energy collisional dissociation techniquesJ. Mass Spectrom.56e4793(2021)DOI: 10.1002/jms.4793
The rapid annotation and identification by mass spectrometry techniques
of flavonoids remains a challenge, due to their structural diversity and
the limited availability of reference standards. This study applies a
workflow to characterize two isoflavonoids, the orobol-C-glycosides
analogs, using high-energy collisional dissociation (HCD)- and
collision-induced dissociation (CID)-type fragmentation patterns, and
also to evaluate the antioxidant effects of these compounds by ferric
reducing antioxidant power (FRAP), 2,2′-azino-bis(3-ethylbenzothiazolin
acid) 6-sulfonic acid (ABTS), and 2,2-diphenyl-1-picrylhydrazyl (DPPH)
methods. By the CID-type fragmentation, in positive mode and at all
high-resolution mass spectrometry (HRMS) multiple stage, there were
shown differences in the annotation of the compounds, mainly concerning
some ratios of relative abundance. At CID-MS2 20 eV, the compounds could be efficiently characterized, because they present distinct base peaks [M + H]+ and [M + H–H2O]+ for the orobol-8-C- and orobol-6-C-glycoside, respectively. Similarly, by the HCD-type fragmentation, in HRMS2 stage, differences between orobol analogs in both mode of ionization were observed. However, the HR HCD-MS2 at 80 eV, in positive mode, generated more ions and each isomer presented different base peaks ions, [0,2X]+ for the orobol-8-C-glycoside and [0,3X]+ for the orobol-6-C-glycoside. By the DPPH, the 8-C-derivative
showed a very close value compared with the standard rutin and, in the
ABTS method, a higher radical-scavenging activity. In both methods, the
EC50 of orobol-8-C-glycoside was almost twice better compared with orobol-6-C-glycoside. In FRAP, both C-glycosides showed a good capacity as Fe+3
reducing agents. We could realize that combined MS techniques,
highlighting the positive mode of ionization, can be used to evaluate
the isoflavones analogs being useful to differentiate between the
isomeric flavones; therefore, these data are important to mass
spectrometry dereplication studies become more efficient.