MITOCHONDRIAL MEMBRANE METABOLIC ROLE OF CYTOCHROME C

细胞色素c是线粒体中唯一的大分子成分。 呼吸链不是体内的一种不可或缺的蛋白质 线粒体膜，但更容易从外部解离 膜的表面进入膜间空间。一大笔钱 关于其运作的许多方面都有信息，但有 仍然缺乏对力学的基本方面的知识 在正常的细胞内生理条件下的功能，以及 它们是否与线粒体的不同状态相关 呼吸链功能。因此，电子之间的转移 细胞色素c的主要但不是唯一的功能--还原酶和氧化酶， 可以在蛋白质很少移动的情况下发生(固态 模型)，通过沿内表面的二维扩散 线粒体膜，通过在膜间隙自由扩散，或 通过这些过程的组合。这样的概念是由 假设自由扩散和自由扩散的动态集料模型 所有电子转移组件的缔合形式，从而使 细胞色素c功能所需的迁移率将取决于比例 这种分离形式和关联形式的平衡。来描述它的 生理功能是否建议：(1)使用新开发的套装 同分异构体细胞色素c衍生物的测定，通过共价法 交联度，细胞色素c上的电子接受位点数 细胞色素c过氧化物酶和其他电子交换伙伴， 细胞色素c结合部位与其相互作用关系的建立 对反应动力学的影响；(2)采用差分共振拉曼光谱 光谱学研究细胞色素c与细胞色素的相互作用 以及细胞色素c过氧化物酶，并确定准确的结合 溶液亲和力；(3)羧基修饰酵母细胞色素c的研究 过氧化物酶和细胞色素b5来验证它们的定位 细胞色素c的相互作用结构域；(4)获得细胞色素c 通过重组DNA程序进行所需的氨基酸残基交换，以及 利用它们来检查结构，这些结构指定了 酵母细胞色素C过氧化物酶的功能适应性 偶极矩与血红素平面夹角恒定的意义， 灵长类和非灵长类细胞色素的功能差异 C；(5)研究细胞色素c的生物合成，以开发 将标记的细胞色素c导入完整的线粒体。

Cytochrome c is the only macromolecular component of the mitochondrial respiratory chain that is not an integral protein of the inner mitochondrial membrane, but rather can readily dissociate from the outer surface of that membrane into the intermembrane space. A wealth of information is available concerning many facets of its operation, but there still exists a lack of knowledge about fundamental aspects of the mechanics of its function under normal intracellular physiological conditions, and whether these are correlated with the various states of mitochondrial respiratory chain function. Thus, the transfer of electrons between reductase and oxidase, the major but not the only function of cytochrome c, could take place with very little movement of the protein (solid state model), by two dimensional diffusion along the outer surface of the inner mitochondrial membrane, by free diffusion in the intermembrane space, or by combinations of these processes. Such a concept is provided by the dynamic aggregate model which postulates both freely diffusing and associated forms of all electron transfer components, so that the degree of mobility required for cytochrome c function will depend on the proportional equilibrium of such dissociated and associated forms. To describe its physiological function is it proposed to: (1) Employ a newly developed set of isomeric cytochrome c derivatives to determine, by covalent cross-linking, the number of electron-accepting sites on cytochrome c oxidase, cytochrome c peroxidase and other electron exchange partners, establishing the relation between the site of cytochrome c binding and its effect on the kinetics of reaction; (2) employ difference resonance Raman spectroscopy to study the interaction between cytochrome c and cytochrome oxidase as well as cytochrome c peroxidase, and determine accurate binding affinities in solution; (3) study carboxyl-modified yeast cytochrome c peroxidase and cytochrome b5 to verify the localization of their interaction domains for cytochrome c; (4) obtain cytochromes c with any desired amino acid residue exchange by recombinant DNA procedures, and employ them to examine the structures that specify the remarkable functional adaptation of yeast cytochrome c peroxidase, the functional significance of the constant angle between dipole moment and heme plane, and the functional difference between primate and non-primate cytochromes c; (5) study the biosynthesis of cytochrome c to develop procedures for introducing labelled cytochrome c into intact mitochondria.