Electron Transfer Reactions Between Cytochrome c, Cytochrome c Oxidase and Dioxygen

该项目得到了分析和表面化学项目的支持，开发了新的电化学方法，用于研究复杂介质中的膜结合酶。 该项目由弗吉尼亚联邦大学的Albert Sneden博士和他的团队进行，该项目制备并表征了吸附在脂质双层上的细胞色素c氧化酶（CCO）的稳定组装体，该脂质双层固定在银涂层的金电极上。石英晶体微载体用于用最佳银层涂覆电极。然后用十八烷基聚乙烯覆盖电极以形成双层的锚。 原子力显微镜用于确认膜的结构。电化学实验已经证实，这种双层模拟CCO的体内反应性。氰化物和CCO之间的已知反应构成了这些研究的基础。在流动条件下还原的细胞色素、双层中的CCO和电极之间的电子转移反应的特征在于作为氰化物浓度、稳态周转率和氧浓度的函数。 该研究为复杂介质中膜结合酶的研究开辟了新的电化学方法。 这项研究的结果将有助于评估化合物作为酶抑制剂的潜在功效，并在药物测试等领域具有重要意义。

This project, which is supported in the Analytical and Surface Chemistry program develops new electrochemical methods for studying membrane-bound enzymes in complex media. Conducted by Dr. Albert Sneden and his group at Virginia Commonwealth University, the project prepares and characterizes stable assemblies of cytochrome c oxidase (CCO) adsorbed on a lipid bilayer that is anchored into a silver-coated gold electrode. A quartz crystal microbabance is used to coat the electrode with an optimum layer of silver. The electrode is then covered with octadectyl mercaptan to form an anchor for the bilayer. Atomic Force Microscopy is used to confirm the structure of the membrane. Electrochemical experiments have confirmed that such a bilayer mimics the in vivo reactivities of CCO. The known reaction between cyanide and CCO forms the basis for these studies. The electron transfer reaction between reduced cytochrome under flow conditions, CCO in the bilayer, and the electrode is characterized as a function of cyanide concentration, steady state turnover rate, and oxygen concentration. This research develops new electrochemical methods for studying membrane-bound enzymes in complex media. Results from this research will be useful for assessing the potential efficacy of compounds as enzyme inhibitors and will be important in areas such as drug testing.