Site-Specific Mutation of Nitrogenase Proteins

二氮还原是通过补充微生物反硝化过程中损失的氨来维持氮循环所必需的。氮酶是一种与电子转移和底物还原相关的Fe:S化学变化的酶的原型例子。此外，它是ATP水解能量转导的优良模型。氮酶的铁蛋白是专性的atp酶依赖的电子转移剂，用于底物还原。为研究铁蛋白如何发挥这一作用，下一个资助期将研究以下问题。1. 4Fe:4S簇是如何在FE-蛋白中组装的，而最终的簇又是如何被加工成活性状态的？2. 铁蛋白中的ATP/ADP结合位点在哪里？核苷酸结合的不同模式是什么？它们是如何引起蛋白质的各种结构-构象变化的？

Dinitrogen reduction is essential for maintenance of the nitrogen cycle by replenishing ammonia lost through microbial denitrifiction Nitrogenase is a prototypic example of an enzyme with varied Fe:S chemistry associated with electron transfer and substrate reduction. In addition, it is an excellent model of energy transduction with ATP hydrolysis. The Fe-protein of nitrogenase is the obligate ATPase dependent electron transfer agent for substrate reduction. To study how Fe-protein functions in this role, the following questions will be investigated in the next grant period. 1. How is the 4Fe:4S cluster assembled in the FE- protein and how is the resultant cluster processed to the active state? 2. Where are the ATP/ADP binding sites in the Fe- protein? What are the different modes of nucleotide binding and how do they elicit the various structural-conformational changes in the protein?