SPECTROSCOPY AND FUNCTION OF REDOX METALLOPROTEINS

这个项目的中心目标是阐明 参与氧化还原金属蛋白功能的因素。我们想要 了解这些蛋白质如何促进电子传递和小分子 分子激活，它们如何施加动力学或热力学控制，以及 他们如何节约或利用他们的过程中的能量 催化。我们的方法强调振动光谱，这是 对结构敏感。特别是，我们强调时间分辨 振动探头。提出了以下具体目标。 血红素-铜氧化物酶。(一)我们希望了解两国之间的差异 不同物种的氧化物酶。(Ii)我们希望检查是否 我们提出的CO的连接机制也适用于O2。(Iii)我们 我想要检验关于两者之间关系的假设 金属中心的配位化学和外源化合物的控制 配体进入、氧化还原反应性和热力学，以及 氧化还原能量到质子转移。 NiFe加氢酶。NiFe氢酶的功能活性部位 含有本征的CN-和CO，这可能是研究最多的振动 化学中的生色团。这提供了使用振动法的机会 解决结构和功能问题的分光镜。这些措施包括： 研究了镍、铁的氧化态变化、电子结构和电子结构 各种形式的双核位置的立体化学，以及它们的 在反应过程中的变化；无论二氢或氢化物物种可能是 重要；以及其他氧化还原辅助因素的同一性。 四氯乙烯(PCE)脱卤酶。就在最近，一种新的酶 完成各种底物的还原脱卤化，PCE 脱卤酶，已被分离和鉴定。这是一种可溶的Co- 以铁-S簇为氧化还原辅因子的皮质醇蛋白。我们想要 Co-Corins和Fe-S团簇的拉曼光谱和红外光谱研究 探讨其氧化还原位点的结构和功能动力学。 酵素。

The central objective of this project is to elucidate the fundamental factors involved in the function of redox metalloproteins. We want to understand how these proteins facilitate electron transfer and small molecule activation, how they exert kinetic or thermodynamic control, and how they conserve or utilize the energy of the processes that they catalyze. Our approaches emphasize vibrational spectroscopies which are sensitive to structure. In particular, we emphasize time-resolved vibrational probes. The following Specific Aims are proposed. Heme-Copper Oxidases. (i) We want to understand the differences among oxidases from different species. (ii) We want to check whether the ligation mechanisms that we have proposed for CO apply to O2. (iii) We want to test the hypothesis concerning the relationships between the coordination chemistry of the metal centers, and the control of exogenous ligand entry, redox reactivity and thermodynamics, and the coupling of redox energy to proton translocation. NiFe Hydrogenases. The functional active site of NiFe hydrogenases contains intrinsic CN- and CO, perhaps the most-studied vibrational chromophores in chemistry. This presents an opportunity to use vibrational spectroscopies to address structural and functional issues. These include: the oxidation state changes of Ni and Fe; the electronic structures and the stereochemistry of the binuclear site in various forms, and their changes during reactivity; whether dihydrogen or hydride species may be important; and the identity of other redox co-factors. Perchloroethylene (PCE) Dehalogenase. Quite recently a novel enzyme that accomplishes reductive dehalogenation of a wide range of substrates, PCE dehalogenase, has been isolated and characterized. This is a soluble Co- corrinoid protein with Fe-S clusters as redox cofactors. We want to exploit the Raman and infrared signatures of Co-corrins and Fe-S clusters to probe the structures and functional dynamics of the redox sites of this enzyme.