ATP-getriebener Elektronentransport der Benzoyl-CoA Reduktase

苯甲酰辅酶A还原酶的ATP驱动电子传递

• 批准号: 5171650
• 负责人: Professor Dr. Matthias Boll
• 金额: --
• 依托单位: Forschungsschwerpunkt Mikrobiologie
• 依托单位国家: 德国
• 项目类别: Priority Programmes
• 财政年份: 1999
• 资助国家: 德国
• 起止时间: 1998-12-31 至 2007-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/5171650?language=en
• 关键词: ATP; getriebener; Elektronentransport; der; Benzoyl

The iron-sulfur-enzyme benzoyl-CoA reductase catalyzes the reduction of benzoyl-CoA to a non-aromatic cyclic diene; this reaction is driven by the hydrolysis of 2 ATP. ATP hydrolysis results in the energetization of an electron and is accompanied by a switch from S = 1/2 to S = 7/2 high-spin EPR signals of the reduced enzyme. In parallel it induces the reversible magnetic interaction of two [4Fe-4S] clusters. We postulate consecutive one-electron transfer and protonation steps in the dearomatization process (Birch reduction). ATP hydrolysis would be coupled to electron activation which is required to overcome the high redox barrier (E'o = -1.9 V) for the first electron transfer to the aromatic ring. Our approaches in getting deeper insights in the structure/function relationships of benzoyl-CoA reductase include spectroscopical (EPR-, Mössbauer-, MCD-spectroscopy), crystallographical/X-ray analytical and molecular biological techniques (heterologous expression of part-activities containing subunits) as well as substrate binding studies. It is possible to investigate the ATP-dependent electron activation separately from the electron transfer to the aromatic ring. We attempt to understand how an enzyme with relatively simple redox modules transfers the energy of ATP hydrolysis into the redox energy required for the dearomatization process.

铁硫酶苯甲酰辅酶A还原酶催化苯甲酰辅酶A还原为非芳香环二烯；该反应是由 2 ATP 的水解驱动的。 ATP 水解导致电子赋能，并伴随着还原酶的高自旋 EPR 信号从 S = 1/2 切换到 S = 7/2。同时它引起两个 [4Fe-4S] 簇的可逆磁相互作用。我们假设脱芳构化过程（Birch 还原）中存在连续的单电子转移和质子化步骤。 ATP 水解将与电子激活相结合，电子激活需要克服高氧化还原势垒 (E'o = -1.9 V)，以便第一次电子转移到芳香环。我们深入了解苯甲酰辅酶A还原酶的结构/功能关系的方法包括光谱（EPR-、穆斯堡尔-、MCD-光谱）、晶体学/X射线分析和分子生物学技术（包含亚基的部分活性的异源表达）以及底物结合研究。可以将 ATP 依赖性电子激活与电子转移到芳环分开进行研究。我们试图了解具有相对简单的氧化还原模块的酶如何将 ATP 水解能量转化为脱芳构化过程所需的氧化还原能量。