Nitrogenase Assembly Mechanism

描述（由申请人提供）：固氮酶是一种复杂的金属酶，催化生物系统中最显著的化学转化之一：将大气中的二氮还原为生物可利用的氨。有一个突出的兴趣解码固氮酶的组装机制，不仅因为它的显着相关性固氮酶的特异性反应，但也因为它的巨大的意义，一般金属蛋白质的生物发生。在这里，我们建议大大扩大我们的理解固氮酶组装过程相结合的遗传，生物化学，光谱和结构的方法。棕色固氮菌钼固氮酶的MoFe蛋白将是研究的重点。通过我们的研究，我们希望进一步完善MoFe蛋白及其相关簇的生物合成途径，这是一项持续的努力，最终目标是解开固氮酶组装的分子机制。此外，使用固氮酶作为模型系统，我们也希望提供生物金属簇组装的一般主题，从长远来看，这可能会证明有助于开发复杂簇的化学合成的成功策略。.公共卫生相关性：固氮酶催化大气中的二氮转化为生物可利用的氨，从而提供人类生存所需的还原态氮，这是核酸和蛋白质的重要组成部分。这一特定的建议涉及固氮酶MoFe蛋白及其相关的簇的组装，这些研究的结果将有望提供生物金属簇组装的一般主题，并促进未来开发具有成本效益的催化活性簇的化学合成策略。因此，我们提出的研究除了与人类健康的内在相关性外，还可能具有额外的经济价值。

DESCRIPTION (provided by applicant): Nitrogenase is a complex metalloenzyme that catalyzes one of the most remarkable chemical transformations in biological systems: the nucleotide-dependent reduction of atmospheric dinitrogen to bioavailable ammonia. There is an outstanding interest in decoding the assembly mechanism of nitrogenase, not only because of its significant relevance to nitrogenase-specific reactions, but also because of its tremendous implication for general metalloprotein biogenesis. Here we propose to greatly expand our understanding of the nitrogenase assembly process by combined genetic, biochemical, spectroscopic and structural approaches. The MoFe protein of the molybdenum nitrogenase of Azotobacter vinelandii will be the focus of the proposed investigation. Through our proposed studies, we expect to further refine the biosynthetic pathways of MoFe protein and its associated clusters, a continuous effort with an ultimate goal to unravel the molecular mechanism of nitrogenase assembly. Furthermore, using nitrogenase as a model system, we also hope to provide general themes of biological metal cluster assembly, which may, in the long run, prove instrumental in developing successful strategies for the chemical synthesis of complex metalloclusters. . PUBLIC HEALTH RELEVANCE: Nitrogenase catalyzes the transformation of atmospheric dinitrogen to bioavailable ammonia, thereby supplying the reduced nitrogen, an essential component of nucleic acids and proteins, for the existence of human population. This particular proposal deals with the assembly of nitrogenase MoFe protein and its associated metalloclusters and the outcome of these studies will hopefully provide general themes of biological metal cluster assembly and facilitate future development of cost-efficient strategies for the chemical synthesis of catalytically active metalloclusters. As such, our proposed research may have additional economic value in addition to its intrinsic relevancy to human health.