Elucidation of reaction mechanisms in the anaerobic degradation of hydrocarbons

阐明碳氢化合物厌氧降解的反应机制

• 批准号: 71718654
• 负责人: Professor Dr. Wolfgang Buckel
• 金额: --
• 依托单位: School of Chemistry (aufgelöst)
• 依托单位国家: 德国
• 项目类别: Priority Programmes
• 财政年份: 2009
• 资助国家: 德国
• 起止时间: 2008-12-31 至 2015-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/71718654?language=en
• 关键词: Elucidation; reaction; mechanisms; anaerobic; degradation

The first part of the proposal aims to deepen our understanding of anaerobic alkane functionalization by the use of substrate analogues in enzymatic studies supported by model studies. The synthetic team at Newcastle will provide labeled substrates (e.g. deuterated decanes) and substrate analogues (e.g. dialkylcyclopropanes) to AG Rabus and AG Wilkes for enzymatic experiments. This work will extend the highly successful cooperation achieved in the first phase of the research. Intermediates for enzymatic studies will also be provided to the Marburg team (substituted malonic and succinic acids for conversion into coenzyme A esters) and AG Heider (‘chiral’ toluene). A new direction will be the development of experimental and theoretical models to improve understanding of the mechanisms of alkane activation. The Newcastle group will continue to provide support to other groups within this SSP (e.g. AG Boll and AG Meckenstock) by synthesizing key intermediates and products, and by giving advice on mechanistic issues in the context of novel catalytic pathways (e.g. benzene carboxylation). For the second part of the proposal the Marburg team will investigate the metabolism of Syntrophus aciditrophicus. The question as to how benzoate degradation and synthesis can proceed via the same enzymes will be studied using the glutaryl-CoA dehydrogenase/electron transferring flavoprotein complex (Gdh/Etf) and the Na+ pumping glutaconyl-CoA decarboxylase (Gcd) as examples. The Marburg team have cloned and functionally expressed four out of six genes coding for these enzymes. The planned studies should reveal whether reduced ferredoxin can drive the oxidation of glutaryl-CoA by NAD+ or whether menaquinone acts as electron acceptor. For reversal of the decarboxylation the source of ΔμNa+ will be identified. The substrate specificity of (Gdh/Etf) will indicate whether the enzyme can be applied for a bio-based production of adipic acid. Finally, the pathway of glutamate synthesis via Re-citrate synthase will be analyzed in more detail.

该提案的第一部分旨在加深我们对厌氧烷烃功能化的理解，通过在模型研究支持的酶促研究中使用底物类似物。纽卡斯尔的合成团队将向AG Rabus和AG Wilkes提供标记底物（例如氘代癸烷）和底物类似物（例如二烷基环丙烷），用于酶促实验。这项工作将扩大在研究第一阶段取得的非常成功的合作。还将向马尔堡团队（用于转化为辅酶A酯的取代丙二酸和琥珀酸）和AG Heider（“手性”甲苯）提供用于酶研究的中间体。一个新的方向将是实验和理论模型的发展，以提高对烷烃活化机制的理解。纽卡斯尔小组将继续通过合成关键中间体和产品，以及在新型催化途径（例如苯羧化）的背景下就机理问题提供建议，为该SSP中的其他小组（例如AG Boll和AG Meckenstock）提供支持。对于提案的第二部分，马尔堡研究小组将研究嗜酸合养菌的代谢。苯甲酸酯降解和合成如何通过相同的酶进行的问题将使用戊二酰辅酶A脱氢酶/电子转移黄素蛋白复合物（Gdh/Etf）和Na+泵戊烯二酰辅酶A脱羧酶（Gcd）作为例子进行研究。马尔堡研究小组已经克隆并功能性表达了编码这些酶的六个基因中的四个。计划中的研究应该揭示还原铁氧还蛋白是否可以通过NAD+驱动戊二酰辅酶A的氧化，或者甲基萘醌是否作为电子受体。为了逆转脱羧作用，将确定ΔμNa+的来源。（Gdh/Etf）的底物特异性将指示该酶是否可以应用于己二酸的生物基生产。最后，将更详细地分析通过Re-柠檬酸合酶的谷氨酸合成途径。