Application of X-ray Absorption Spectroscopy to Study Structure in Chemical and Biological Systems

在这个由实验物理化学和分子与细胞生物科学联合资助的项目中，斯坦福大学的基思·霍奇森将使用X射线吸收光谱来研究化学和生物系统中金属离子位置的结构和功能。研究内容包括金属氧化态对蛋白质结构和反应活性的影响、固氮酶中配体结合的机理、甲烷单加氧酶反应循环中中间体的结构表征以及无机簇合物和桥联金属组合物结构的阐明。还将开发扩展化学体系多重散射分析的理论处理，并将其应用于这些体系。金属中心在生物分子的特定功能中起着关键作用。铁是血红蛋白的重要组成部分，也存在于固氮酶中，固氮酶是一种将大气中的氮转化为氨的分子，氨是天然的肥料之一。这项研究将确定各种生物重要系统中金属位置的结构、反应性和成键。这些信息将有助于生产具有适合特殊需要的化学特性的酶，例如无害环境的化肥生产。

In this project jointly funded by Experimental Physical Chemistry and Molecular and Cellular Biosciences, Keith Hodgson of Stanford University will use x-ray absorption spectroscopies to investigate the structure and function of metal ion sites in chemical and biological systems. Studies include the effect of metal oxidation state on structure and reactivity in proteins such as quinol oxidase, the mechanism of ligand binding in nitrogenase, the structural characterization of intermediates in the methane monooxygenase enzyme reaction cycle, and the elucidation of the structures of inorganic cluster complexes and bridged metal assemblies. Theoretical treatments to extend multiple scattering analysis for chemical systems will also be developed and applied to these systems. Metal sites play a key role in the specific function of biological molecules. Iron, an important component of hemoglobin, is also present in nitrogenase, the molecule which converts atmospheric nitrogen to ammonia, one of nature's fertilizers. This research will determine the structures, reactivities, and bonding of metal sites in a variety of biologically important systems. This information will be valuable in the effort to produce enzymes with chemical characteristics suited to particular needs such as the environmentally benign production of fertilizer.