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

该项目的目的是阐明新的甘氨酰自由基酶-苯基琥珀酸合酶的生物化学，该酶是甲苯厌氧分解代谢中的第一个酶，以及其他参与含甲基芳香族化合物厌氧代谢的酶，它们有望表现出相似的生化特征。对丁二酸苄酯合成酶的研究包括：(I)迄今通过自由基进行的假想反应机制的生化和光谱证明，(Ii)导致自由基形式产生的激活反应的建立和特征，以及(Iii)确定与酶结合的自由基是否像其他甘氨酸基酶那样被失活酶可逆地移除。此外，计划(Iv)将研究扩展到其他烷基苯类和含有甲基取代基的极性芳香族化合物，如间二甲苯、间甲酚、对异丙基甲苯(对伞花烃)和苯甲酸甲酯的厌氧分解代谢的起始酶。

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.