XAS STUDIES OF NITROGENASE, ITS COFACTOR & COFACTOR CLUSTER

重大进展，由最近的结晶学突显 在理解结构时，已经做出了结构上的决定 复合固氮酶中的多核金属中心。 已知存在一个Mo-Fe-S团簇，它在 蛋白质已建立。重要问题仍然存在，包括i) FeMoco结构外部与内部的关系 蛋白质；ii)了解高柠檬酸和pH依赖的作用 对固氮酶的影响；iii)确定底物的位置和方式 抑制剂结合；以及iv)建立高精度的测量细节 对于蛋白质内部和外部的FeMoco。X射线吸收 使用SR的光谱学(EDGE和EXAFS)非常适合于 提供对选定的电子和节拍结构的见解 原子弹的位置。

Significant progress, highlighted by recent crystallographic structual determinations, has been made in understanding the structure of the polynuclear metal centers in the complex nitrogenase enzyme. The presence of a Mo-Fe-S cluster is known and its ligation within the protein established. Important questions remain that include i) relationship of the FeMoco structure outside of, to that within, the protein; ii) understanding the role of homocitrate and of pH-dependent effects on nitrogenase; iii) determining where and how substrate and inhibitors bind; and iv) establishing highly accurate metrical details for the FeMoco both within and outside the protein. X-ray absorption spectroscopy (both edge and EXAFS) using SR is well-suited to providing insights into electronic and metrical structure of selected atomic sites.