Structure and Function of Nifl1-2, A Novel Inhibitor of Nitrogenase Activity in th Earchaeon Methanococcus Maripaludis

新型马里帕卢迪斯甲烷球菌固氮酶活性抑制剂 Nifl1-2 的结构和功能

• 批准号: 0743864
• 负责人: John Leigh
• 金额: $ 45万
• 依托单位: University of Washington
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2008
• 资助国家: 美国
• 起止时间: 2008-08-01 至 2012-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0743864&HistoricalAwards=false
• 关键词: Structure; Function; Nifl1; Novel; Inhibitor

Biological nitrogen fixation is a widespread metabolic process that converts atmospheric nitrogen into fertilizer through the biological activity of certain microorganisms. This project follows up on a newly discovered mechanism by which many organisms regulate the activity of nitrogenase, the enzyme that catalyses the biochemical reactions that result in nitrogen fixation. The mechanism involves a family of proteins called PII proteins that regulates nitrogen metabolic functions in a variety of organisms. The particular proteins to be studied in this research are the NifI proteins, which constitute a previously uncharacterized subfamily of PII proteins. Novel features of NifI and its regulation of nitrogenase activity include the formation a direct complex between NifI and the molybdenum-iron protein of nitrogenase, and formation of novel higher order structures of NifI complexed with itself. The research will involve biochemical, genetic, and protein structural studies using the model microbial species Methanococcus maripaludis, a member of the phylogenetic domain Archaea.The broader impacts of the research are environmental, agricultural, and educational. Biological nitrogen fixation contributes to the nutrition of microorganisms and the plants with which they associate, without the adverse environmental effects associated with chemical fertilizers. The work will also result in the training of personnel in the areas of microbiology and biochemistry, including the integration of protein structure with the biology of nitrogen fixation. Finally, the work feeds into the investigator's teaching and outreach efforts, which include courses featuring microbial metabolism, participation in the University of Washington's interdisciplinary graduate program in Astrobiology, and participation in a K-12 outreach program called project Astrobio.

生物固氮是一种广泛的代谢过程，通过某些微生物的生物活性将大气中的氮转化为肥料。这个项目是对一个新发现的机制的后续研究，通过这个机制，许多生物体调节了固氮酶的活性，这种酶催化了导致固氮的生化反应。这种机制涉及到一个叫做PII蛋白的蛋白质家族，它在多种生物体中调节氮代谢功能。本研究中要研究的特定蛋白质是NifI蛋白，它构成了以前未表征的PII蛋白亚家族。NifI的新特性及其对氮酶活性的调节包括在NifI与氮酶的钼铁蛋白之间形成直接复合物，以及NifI与自身络合形成新的高阶结构。这项研究将涉及生化、遗传和蛋白质结构研究，使用模型微生物物种马里帕鲁迪甲烷球菌（Methanococcus maripaludis），这是系统发育领域古细菌的一员。这项研究的更广泛影响是环境、农业和教育。生物固氮有助于微生物和与之相关的植物的营养，而不会产生与化肥相关的不利环境影响。这项工作还将培训微生物学和生物化学领域的人员，包括将蛋白质结构与固氮生物学结合起来。最后，这项工作将纳入研究者的教学和推广工作，包括微生物代谢课程，参与华盛顿大学天体生物学跨学科研究生课程，以及参与一个名为“天体生物学项目”的K-12推广计划。