Nitrogenase assembly mechanism

固氮酶组装机制

• 批准号: 10524039
• 负责人: Markus W Ribbe
• 金额: $ 34.07万
• 依托单位: UNIVERSITY OF CALIFORNIA-IRVINE
• 依托单位国家: 美国
• 财政年份: 2003
• 资助国家: 美国
• 起止时间: 2003-05-01 至 2024-11-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10524039
• 关键词: Binding; Biochemical; Biomimetics; Carbon; Chemicals; Complex; Coupling; Cryoelectron Microscopy; Crystallography; Enzymes; Genetic; Health; Human; Knowledge; Molybdenum; Nitrogen; Nitrogenase; Pathway interactions; Population; Reaction; Research; Selenite; Source; Sulfites; Sulfur; Variant; analog; biological systems; carbene; catalyst; chemical synthesis; deprotonation; homocitrate; in vivo; insight; interstitial; methyl group; tellurite; usability

PROJECT SUMMARY Nitrogenase reaction represents a major source of the usable form of nitrogen that supports the existence of human population. As such, understanding how small building blocks are assembled into a functional nitrogenase entity is of significant relevance to human health. Using combined genetic, biochemical, spectroscopic and structural approaches, we propose to investigate how M-cluster, the unique metallocofactor of molybdenum nitrogenase, is assembled into a functional unit. Specifically, we will investigate how an interstitial carbide is inserted via a radical SAM-dependent mechanism concomitant with fusion of two 4Fe modules into an 8Fe core of the M-cluster, what is the in vivo donor/carrier of the “9th sulfur” and how this sulfur is inserted into the catalytically important belt region of the 8Fe core, and how Mo is mobilized and inserted into the 8Fe core to form a mature M-cluster. Through our proposed studies, we expect to further refine the biosynthetic pathway of the unique metallocofactor of nitrogenase, which will provide crucial insights into the structural-functional relationship of this important enzyme and reveal some general principles of the assembly mechanisms of complex metalloclusters in biological systems.

项目摘要 氮酶反应代表了支持氮的可用形式的主要来源 人口的存在。因此，了解构建块的小 组装成功能性氮酶实体与人类健康具有重要意义。使用 遗传，生化，光谱和结构方法结合，我们建议 研究M-Cluster是如何的钼氮基因属性的独特金属生产者 组装成功能单元。具体而言，我们将研究核苷的间隙 通过与两个4FE模块融合的自由基SAM依赖机制插入 进入M-Cluster的8FE核心，“第9硫”的体内供体/载体是什么？ 硫被插入8FE核心的催化重要皮带区域，以及MO的方式 动员并插入8FE核心形成成熟的M群集。通过我们的建议 研究，我们希望进一步完善独特的金属生物活性剂的生物合成途径 氮酶，将为这一关系提供重要的见解 重要的酶并揭示了复杂的装配机理的一些一般原理 生物系统中的金属簇。