Reaction mechanism and activation reaction of benzylsuccinate synthase, a novel glycyl-radical-enzyme

• Applicant: Professor Dr. Johann Heider
• Subject Area: Metabolism, Biochemistry and Genetics of Microorganisms
• Term: from 1999 to 2006
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 5176953

The aim of the project is to elucidate the biochemistry of the new glycyl-radical-enzyme benzylsuccinate synthase, the first enzyme in anaerobic toluene catabolism, and other enzymes involved in anaerobic metabolism of methyl-containing aromatic compounds, which are expected to exhibit similar biochemical features. Work on benzylsuccinate synthase involves (i) biochemical and spectroscopic proof for the so far hypothetical reaction mechanism via free radicals, (ii) the establishment and characterisation of the activation reaction leading to generation of the radical form, and (iii) working out whether the enzyme-bound radical is reversibly removed by a deactivating enzyme, as known for other glycyl-radical enzymes. Furthermore, it is planned (iv) to extend the investigations to the initial enzymes of anaerobic catabolism of other alkylbenzenes and polar aromatic compounds containing methyl-substituents, such as m-xylene, m-cresol, p-isopropyltoluene (p-cymene) and the methylbenzoates.

• DFG Programme: Priority Programmes
• Subproject of: SPP 1071: Radikale in der enzymatischen Katalyse