Spectroscopic Studies of Blue Copper and Iron Sulfur Electron Transfer Active Sites

蓝铜和铁硫电子转移活性位点的光谱研究

• 批准号: 9528250
• 负责人: Edward Solomon
• 金额: $ 56.77万
• 依托单位: Stanford University
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 1996
• 资助国家: 美国
• 起止时间: 1996-03-01 至 2001-02-28
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9528250&HistoricalAwards=false
• 关键词: Spectroscopic; Studies; Blue; Copper; Iron

Professor Solomon of Stanford University will conduct studies on metal-containing active sites which have unique spectral features relative to small molecule complexes of the same ion. The general goal is to understand these features in terms of the active site geometric and electronic structural contributions to the reactivity of these sites in biology. The proteins of interest are the blue copper and iron-sulfur centers which occur in biological electron transfer. The unique spectral features of these systems in their natural state reflect novel electronic structures which affect the reduction potentials and the kinetics of electron transfer. Specifically, the studies are directed at `perturbed` blue copper sites which occur naturally or in mutated proteins and have significant spectral and reactivity differences relative to classic blue copper sites, and at a thorough understanding of the complete orbital pathway for electron coupling over the blue copper-Cys-His-Type 2 (or Type 3) unit involved in intramolecular electron transfer in nitrite reductase and the multicopper oxidases. The iron-sulfur studies will focus on the contribution of the electronics to the redox properties of the rubredoxin iron-sulfur center, and extension to 2- and 4-iron sulfur centers and to heterometal clusters. The ultimate goal in these studies is to experimentally determine the changes in electronic structure associated with coupling to additional metal centers and to understand the contributions of electron delocalization to the reduction potentials and electron transfer reactivity. A diverse array of sophisticated spectroscopic techniques will be used to learn about the bonding at the active sites of two classes of metal-containing proteins. These proteins contain either copper-sulfur or iron-sulfur centers, are found in most organisms, and function in the physiological electron transport chains. The approach to be taken will entail detailed experimental and theoretical study of simple models of the active sites, as well as experimental study of a series of modified copper proteins. The information obtained will lead to an understanding of how the bonding at the metal sites controls the rates and energetics of reactions of these proteins.

斯坦福大学的所罗门教授将对 具有独特光谱特征的含金属活性位点 相对于相同离子的小分子复合物。 总目标 是从活性部位的几何学角度理解这些特征， 电子结构的贡献，这些网站的反应性， 生物学 感兴趣的蛋白质是蓝铜和铁硫 在生物电子传递中发生的中心。独特的光谱 这些系统在其自然状态下的特征反映了新的电子 影响还原电位和动力学的结构 电子转移 具体而言，这些研究是针对“扰动” 蓝铜位点，天然存在或突变蛋白质中， 相对于经典蓝显着的光谱和反应性差异 铜网站，并在一个完整的轨道彻底了解 通过蓝铜-Cys-His-2型（或 亚硝酸根分子内电子转移的3）型单元 还原酶和多铜氧化酶。铁硫研究将 专注于电子对氧化还原性能的贡献， Rubredoxin铁硫中心，并延伸至2-和4-铁硫 中心和杂金属簇。 这些研究的最终目的 是通过实验确定电子结构的变化 与其他金属中心的耦合有关， 电子离域对还原电位的贡献 和电子转移反应性。 一系列复杂的光谱技术将用于 了解两类分子的活性位点的键合 含金属的蛋白质这些蛋白质含有铜硫或 铁硫中心，在大多数生物体中发现，并在 生理电子传递链 所采取的办法将 需要详细的实验和理论研究的简单模型， 活性位点，以及一系列改性的实验研究 铜蛋白 所获得的信息将导致理解 金属点的键合是如何控制 这些蛋白质的反应。