ORGANIZATION AND CONTROL OF ELECTRON TRANSFER CHAINS

这项研究的目的是阐明蛋白质的结构要求 线粒体电子转移链中的电子转移和控制，以及 在微粒体NADPH细胞色素C(P450)还原酶系统中。有建议说 将氧耗控制在细胞色素氧化酶的水平上可能 涉及一种类似于为血红蛋白定义的机制，其中 亚基之间的静电相互作用决定氧的亲和力 在亚铁血红素处结合。在细胞色素氧化酶的情况下，强离子 与其底物细胞色素c的相互作用可能会影响 氧化物酶的构象，以及膜电位的梯度。其影响 呼吸道细胞色素c的存在、缺失和结合亲和力 我们将研究耦合内线粒体膜的控制。稳定状态， 反应的预稳态态和低温动力学分析 将进行细胞色素c氧化酶的天然和修饰细胞色素c。 与纯化的单分散氧化物酶制剂以及与 膜结合形式，以进一步阐明其作用机理和机理。 这种反应。这还需要直接的约束性研究和 共价交联细胞色素c-TO的动力学效应研究 纯化的和膜结合的酶。细胞色素c与细胞色素C的反应 微粒体NADPH-细胞色素C(P450)还原酶将作为一种 细胞色素C结构的功能，离子强度，细胞色素P450的存在， 以及还原酶制剂的类型(酶溶解、洗涤剂 溶解的和膜结合的)，以定义蛋白质的性质 涉及的互动。

The aim of this research is to elucidate the protein structural requirements for electron transfer and control in the mitochondrial electron transfer chain, and in the microsomal NADPH cytochrome c (P450) reductase system. It is proposed that control of oxygen consumption at the level of cytochrome oxidase may involve a mechanism similar to that defined for hemoglobin, in which changes in electrostatic interactions between subunits determine the affinity of oxygen binding at the heme. In the case of cytochrome oxidase, the strong ionic interactions with its substrate, cytochrome c, are likely to influence the conformation of the oxidase, as is the membrane potential gradient. The effects of the presence, absence and binding affinity of cytochrome c on respiratory control in coupled inner mitochondrial membranes will be studied. Steady-state, pre-steady state, and low-temperature kinetic analyses of the reactions of native and modified cytochromes c with cytochrome c oxidase will be carried out with a purified, mono disperse oxidase preparation, as well as with the membrane-bound form, in order to further clarify the mechanism and mechanics of the reaction. This will also require direct binding studies and an investigation of the kinetic effects of covalently cross-linking cytochrome c to purified and membrane-bound oxidase. The reaction of cytochrome c with microsomal NADPH-cytochrome c (P450) reductase will be investigated as a function of cytochrome c structure, ionic strength, presence of cytochrome P450, and the type of reductase preparation (protease-solubilized, detergent solubilized, and membrane-bound), in order to define the nature of the protein interactions involved.