UNDERSTANDING THE MOLECULAR DETAILS OF BIOLOGICAL METHANE FORMATION

了解生物甲烷形成的分子细节

• 批准号: 7726004
• 负责人: CAROLINE MARY WILMOT
• 金额: $ 1.98万
• 依托单位: UNIVERSITY OF CHICAGO
• 依托单位国家: 美国
• 财政年份: 2008
• 资助国家: 美国
• 起止时间: 2008-09-01 至 2009-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7726004
• 关键词: Archaea; Biological; Coenzymes; Collaborations; Computer Retrieval of Information on Scientific Projects Database; Condition; Disulfides; Electrons; Enzymes; Face; Freezing; Funding; Generations; Grant; Hand; Institution; Metabolism; Methane; Methanobacteria; Michigan; Microbe; Molecular; Nature; Nickel; Oxidation-Reduction; Production; Reaction; Research; Research Personnel; Resolution; Resources; Source; Structure; Tetrapyrroles; Today; United States National Institutes of Health; Universities; coenzyme B; electron donor; greenhouse gases; inorganic phosphate; medical schools; methyl coenzyme M; methyl coenzyme M reductase

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. The anaerobic methanogenic archaea (methanogens) form methane as an end product of their metabolism. It has been estimated that methanogens produce approximately 1 billion tons of methane every year. Methane is a potent greenhouse gas, but also represents a potential valuable source of renewable energy. This ?double-edged sword? makes the study of biological methane generation of relevance to two of the most critical challenges we face in the World today. Found in all methanogens, methyl-coenzyme M reductase (MCR) catalyzes the final step in biological methane production. Methyl-coenzyme M (methyl-SCoM, 2-(methylthio)ethanesulfonate) and coenzyme B (CoBSH, N-7-mercaptoheptanoylthreonine phosphate) are the substrates for the reaction, in which CoBSH serves as the electron donor for the 2 electron reduction of methyl-SCoM to produce methane and a CoBS-SCoM mixed disulfide. MCR contains coenzyme F430, a redox active nickel tetrahydrocorphin that is the most reduced tetrapyrrole known in nature. The large reduction potential of coenzyme F430 means that stabilizing the reduced and active form of the enzyme for structural studies has proved impossible up to this point. Crystallographic studies thus far have been conducted with oxidized catalytically inactive forms. In collaboration with Steve Ragsdale (University of Michigan Medical School) we now believe we can generate the active form of the enzyme, MCRred1, at ~70% occupancy in single crystals through maintaining anaerobic conditions from microbe grow-up to crystal freezing. With these crystals in hand, a plethora of freeze trapped intermediates and inhibited forms become accessible. The high diffraction quality of the crystals (up to 1.2 Angstroms resolution) allows us to understand how structure relates to function in this highly unusual enzyme.

该副本是利用众多研究子项目之一 由NIH/NCRR资助的中心赠款提供的资源。子弹和 调查员（PI）可能已经从其他NIH来源获得了主要资金， 因此可以在其他清晰的条目中代表。列出的机构是 对于中心，这不一定是调查员的机构。 厌氧甲烷古细菌（甲烷剂）形成甲烷作为其代谢的最终产物。据估计，每年甲烷生产约10亿吨甲烷。甲烷是一种有效的温室气体，但也代表了可再生能源的潜在宝贵来源。这剑吗？研究与当今世界面临的两个最关键的挑战的生物甲烷产生相关性。在所有甲烷元素中发现，甲基酶M还原酶（MCR）催化了生物甲烷的最后一步。甲基辅酶M（甲基-SCOM，2-（甲基硫硫代）乙酸）和辅酶B（Cobsh，N-7-甲基磷酸硫酸磷酸盐）是反应的底物，在该反应中是2 cobsh cobsh作为甲基甲基甲烷和甲基复合物的电子供体的cobsh供体，可用于甲基甲基甲烷和甲基甲烷，并为A甲基复合物，并为A甲基复合物均可用于甲基甲烷和甲烷。 MCR包含辅酶F430，这是一种氧化还原活性镍四氢可球复，是自然界中已知的四吡咯。辅酶F430的巨大还原潜力意味着，稳定酶的结构研究的降低和活性形式已被证明是不可能到此为止的。迄今为止，晶体学研究是用氧化催化无效的形式进行的。通过与密歇根大学医学院的史蒂夫·拉格斯代尔（Steve Ragsdale）合作，我们相信我们可以通过维持从微生物长大到晶体冷冻的厌氧条件来生成单晶的活跃形式，即McRred1的活跃形式，单晶的占用率约为70％。借助这些晶体，可以使用大量的冻结中间体和抑制形式。晶体的高衍射质量（分辨率高达1.2埃埃斯特罗姆）使我们能够了解结构与这种高度不寻常的酶的功能之间的关系。