Characterization of a novel type of benzene ring reductase in Geobacter metallireducens

• Applicant: Professor Dr. Matthias Boll
• Subject Area: Microbial Ecology and Applied Microbiology
• Term: from 2006 to 2010
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 25576161

Benzoyl-CoA is a key intermediate of anaerobic aromatic metabolism in both, facultatively and strictly anaerobic bacteria. Facultative anaerobes utilize an ATP-dependent ring reductase for the dearomatization of benzoyl-CoA to a two-electron reduced cyclic dienoyl-CoA compound. In the strictly anaerobic model organism Geobacter metallireducens, benzoyl-CoA dearomatization also appears to be accomplished by reduction, although the four structural genes of ATP-dependent benzoyl-CoA reductase are missing. Instead, eight so far unknown proteins, encoded by the benzoate-induced bamB-I genes, were recently identified by our group. They comprise subunits of Mo- and selenocysteine-proteins, and heterodisulfide reductases and hydrogenases-like proteins, most possibly forming a complex. In this project, the composition and function of the individual components/or the putative enzyme complex in benzene ring dearomatization of a strictly anaerobic model organism will be studied for the first time. A number of biochemical, immunological, spectroscopic and electrochemical techniques will be applied. The results obtained should reveal insights into a novel enzymatic principle.

• DFG Programme: Research Grants