电辅助Methanobacterium palustre 还原二氧化碳产甲烷机理研究

电辅助产甲烷菌还原二氧化碳产甲烷系统以产甲烷菌为生物催化剂，在较低能量输入下催化质子、电子及二氧化碳合成甲烷，是一种兼顾环境与能源问题的新技术，但是这一过程作用机制尚不清楚。本项目拟以M.palustre为模式微生物，通过M.palustre产甲烷时胞内还原态铁氧还原蛋白（Fdred2-）、还原态辅酶F420（F420H2）、辅酶M、辅酶B产生机制及二氧化碳还原过程中胞内质子代谢途径和电子传递途径的研究，揭示M.palustre直接利用质子、电子及二氧化碳合成甲烷的机制，然后通过分析M.palustre表面是否存在纳米导线和细胞色素解析M.palustre与电极间电子传递机制，进而从以上两个方面阐明电辅助M.palustre还原二氧化碳产甲烷机理，为电辅助电活性产甲烷菌产甲烷研究奠定理论基础，同时为电辅助电活性产甲烷菌还原二氧化碳高效产甲烷研究提供技术支持。

The electrochemically assisted reduction of carbon dioxide to methane by electromethanogenesis system uses electromethanogenesis as biological catalyst to catalyze proton, electron and carbon dioxide to synthesize methane at low energy input. It is a new technology which can solve both of environmental and energy problems that human faces. However, the mechanism of this process is still unclear. The aim of this project is intended to use M.palustre as a model microorganism to research the mechanism of electrochemically assisted reduction of carbon dioxide to methane by electromethanogenesis. First, the mechanism of direct using proton, electron and carbon dioxide to synthesize methane within M.palustre was revealed via analyzing the production mechanism of reduced ferredoxin (Fdred2-), reduced coenzyme F420 (F420H2), coenzyme M, and coenzyme B, and via analyzing the pathway of proton metabolism and electron transfer within M.palustre in the process of carbon dioxide reduction. Then the mechanism of electron transfer between M.palustre and electrode was demonstrated through analyzing either the existence of nanowire and cytochrome on M.palustre surface or not. After that, we would like to in-depth understand the mechanism of electrochemically assisted reduction of carbon dioxide to methane by electromethanogenesis from two aspects mentioned above. The project explores the mechanism of electrochemically assisted reduction of carbon dioxide to methane by M.palustre, which would pave the way for the research on electrochemically assisted reduction of carbon dioxide to methane by electromethanogenesis. Meanwhile, it would also provide technical support for the research on efficient production of methane by electrochemically assisted reduction of carbon dioxide to methane with electromethanogenesis.