Le chimiste français Marc Fontecave en visite en Suède
Marc Fontecave is the head of the CEA biocatalysis lab (Grenoble) and a professor at Collège de France (Paris). He is the current holder of the chair : Chemistry of biological processes.
From enzymes to catalysts : new electrode materials for fuel cells and photoelectrolyzers
One of the grand challenges of twenty-first century chemistry is to convert abundant energy-poor molecules to energy rich molecules using sunlight as the energy source. Hydrogen from water is such a solar fuel. However its production and use currently depend on noble metals such as Platinum which is expensive and not abundant enough. Viable renewable energy systems will require new catalysts made from earth-abundant materials, cheap and robust. We will describe our bioinspired strategy, aiming at reproducing hydrogenase active sites, which leads to remarkable Cobalt-based and Nickel-based (photo)catalysts for hydrogen production and oxidation.
Date & Time : 2011-02-23, 15.15-16:15
Place : Uppsala University, Ångström laboratory, Department of Photochemistry & Molecular Science, Häggsalen
Date & Time : 2011-03-01, 15.00-16:00
Place : KTH, Teknikringen 30, Floor 7, Erdtmanrummet
Iron-sulfur clusters and radical biocatalysis : modification of macromolecules
Radical-SAM enzymes constitute a very large family of iron sulphur proteins involved in a great variety of metabolic pathways and biosynthetic reactions. The active site, a complex between a [4Fe-4S] cluster and S-adenosylmethionine (SAM), serves to generate free radicals for reaction initiation. This unique and complex radical chemistry has been recently shown to be used in Nature during the specific modification of biological macromolecules : DNA, transfer RNA and proteins. This will be specifically illustrated through examples of enzymes studied in our laboratory. First, mechanistic studies of the sporephotoproduct lyase, an enzyme essential for repairing DNA in pathogenic sporulating bacteria exposed to UV radiation, will be discussed. Second, enzymes participating in the biosynthesis of sulfur-containing compounds and catalyzing C-H to C-S bond formation, will be presented with special emphasis on methylthio-transferases present in both prokaryotes and eukaryotes involved in the specific methylthiolation of tRNAs, as well as on a methylthio-transferase involved in the methylthiolation of a specific aspartate residue of a ribosomal protein.
Date & Time : 2011-02-24 11:00-12:00
Place : Uppsala University, BMC, Husargatan 3 ; room C8:305
Date & Time : 2011-02-28 15:00-16:00
Place : Stockholm University, Arrhenius laboratory (Universitetsvägen, 10A)