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…
Wessjohann, L. A.; Rivera, D. G.; León, F.;Freezing Imine Exchange in Dynamic Combinatorial Libraries with Ugi Reactions: Versatile Access to Templated MacrocyclesOrg. Lett.94733-4736(2007)DOI: 10.1021/ol7021033
A novel approach to freeze the imine exchange process in dynamic combinatorial libraries by Ugi reactions was developed. Macrocyclic oligoimine libraries previously formed and altered by addition of metal templates are efficiently quenched by multiple multicomponent reactions. The approach may be considered as an alternative to the typical reduction with borohydrides and delivers polyazamacrocycles with variable side arms. High dilution is not required to achieve high yields.
Publikation
Wasternack, C.;Jasmonates: An Update on Biosynthesis, Signal Transduction and Action in Plant Stress Response, Growth and DevelopmentAnn. Bot.100681-697(2007)DOI: 10.1093/aob/mcm079
BackgroundJasmonates are ubiquitously occurring lipid-derived compounds with signal functions in plant responses to abiotic and biotic stresses, as well as in plant growth and development. Jasmonic acid and its various metabolites are members of the oxylipin family. Many of them alter gene expression positively or negatively in a regulatory network with synergistic and antagonistic effects in relation to other plant hormones such as salicylate, auxin, ethylene and abscisic acid.ScopeThis review summarizes biosynthesis and signal transduction of jasmonates with emphasis on new findings in relation to enzymes, their crystal structure, new compounds detected in the oxylipin and jasmonate families, and newly found functions.ConclusionsCrystal structure of enzymes in jasmonate biosynthesis, increasing number of jasmonate metabolites and newly identified components of the jasmonate signal-transduction pathway, including specifically acting transcription factors, have led to new insights into jasmonate action, but its receptor(s) is/are still missing, in contrast to all other plant hormones.
Publikation
Wasternack, C.;Clarence A. “Bud” Ryan (29.09.1931–07.10.2007)Plant Mol. Biol.65709-709(2007)DOI: 10.1007/s11103-007-9254-8
Walter, M. H.; Floß, D. S.; Hans, J.; Fester, T.; Strack, D.;Apocarotenoid biosynthesis in arbuscular mycorrhizal roots: Contributions from methylerythritol phosphate pathway isogenes and tools for its manipulationPhytochemistry68130-138(2007)DOI: 10.1016/j.phytochem.2006.09.032
During colonization by arbuscular mycorrhizal (AM) fungi plant roots frequently accumulate two types of apocarotenoids (carotenoid cleavage products). Both compounds, C14 mycorradicin and C13 cyclohexenone derivatives, are predicted to originate from a common C40 carotenoid precursor. Mycorradicin is the chromophore of the “yellow pigment” responsible for the long-known yellow discoloration of colonized roots. The biosynthesis of apocarotenoids has been investigated with a focus on the two first steps of the methylerythritol phosphate (MEP) pathway catalyzed by 1-deoxy-d-xylulose 5-phosphate synthase (DXS) and 1-deoxy-d-xylulose 5-phosphate reductoisomerase (DXR). In Medicago truncatula and other plants the DXS2 isogene appears to be specifically involved in the AM-mediated accumulation of apocarotenoids, whereas in the case of DXR a single gene contributes to both housekeeping and mycorrhizal (apo)carotenoid biosynthesis. Immunolocalization of DXR in mycorrhizal maize roots indicated an arbuscule-associated protein deposition, which occurs late in arbuscule development and accompanies arbuscule degeneration and breakdown. The DXS2 isogene is being developed as a tool to knock-down apocarotenoid biosynthesis in mycorrhizal roots by an RNAi strategy. Preliminary results from this approach provide starting points to suggest a new kind of function for apocarotenoids in mycorrhizal roots.