BIOLOGICAL ELECTRON TRANSFER

目的是了解生物电子的机制。 以分子的形式转移。此外，根据建议的性质， 研究了对生物学特异性的实质性了解，这些因素 介导蛋白质-蛋白质和蛋白质-膜相互作用 我们将获得蛋白质的结构-功能关系。电子 传递和耦合能量守恒是生命的基础 因此，如果我们想要了解这些现象，就需要了解这些现象 充分了解活细胞。众所周知，开车 力、静电学、距离/立体、取向、介电介质和 蛋白质动力学在控制电子的动力学方面都起着作用。 分子间的转移。为了充分量化每个角色的作用 在这些因素中，我们提议开发五种特定的氧化还原蛋白 它们大体上具有相似但不同的电子转移性质。 之所以选择这些系统，是因为它们各自具有不同的特性 易于分析的控制生物的因素 电子转移。主要的方法是使用瞬变动力学 作为对功能的分析，使用可用来解释动力学 结构信息和计算机图形学，并使用 分子生物学(定点突变)充分利用这些 系统。我们的具体目标包括：a)确定 第I类c型细胞色素(RPS.囊状细胞色素c2)， 铁硫蛋白(白色坎皮铁氧还蛋白)和铜蛋白(白色 在它们与生理和生理的相互作用方面) 非生理性反应物提供有关中介因素的信息 这些体系中的电子转移，b)一组结构分析 高潜势铁-硫蛋白获得有关控制的信息 氧化还原电位、蛋白质折叠和系统发育，c) RPS细胞色素b/c1的特性。胶囊，这是一个示例 复合(多色)膜蛋白，将提供信息 关于复合体内电子转移和与细胞色素c2的相互作用，以及 C)通过对不同蛋白质的比较研究，得出总体上的结论 对生物电子转移的认识及开发途径 其他特性不太好的系统。

The objective is to understand the mechanism of biological electron transfer in molecular terms. Moreover, by the nature of the proposed studies a substantial understanding of biological specificity, the factors mediating protein-protein and protein-membrane interactions and structure-function relations in proteins will be obtained. Electron transfer and coupled energy conservation are fundamental to the life process thus an understanding of these phenomena is required if we are to fully understand the living cell. It is well established that driving force, electrostatics, distance/sterics, orientation, intervening media and protein dynamics all play a role in controlling the kinetics of electron transfer between molecules. In order to fully quantitate the role of each of these factors, we are proposing to exploit five specific redox proteins which have generally similar but distinct electron transfer properties. These systems were chosen as they each have different characteristics amenable to analysis in terms of the factors controlling biological electron transfer. The principal approaches are to use transient kinetics as an assay of function, interpretation of kinetics using available structural information and computer graphics, and using the techniques of molecular biology (site directed mutagenesis) to fully exploit these systems. Our specific aims include the following: a) characterization of examples of Class I c-type cytochromes (Rps. capsulata cytochrome c2), iron-sulfur proteins (white campion ferredoxin) and copper proteins (white campion plastocyanin) in terms of their interaction with physiological and non-physiological reactants to provide information on the factors mediating electron transfers in these systems, b) structural analysis of a group of high potential iron-sulfur proteins to obtain information on the control of oxidation-reduction potentials, protein folding, and phylogeny, c) characterization of cytochrome b/c1, from Rps. capsulata, an example of a complex (multichromophoric) membrane protein which will provide information on intracomplex electron transfer and interaction with cytochrome c2, and c) through comparison of the different protein studies derive a general understanding of biological electron transfer and the means to exploit other less well characterized systems.