Metalloprotein Electron Transfer Mechanisms

在这个由无机，生物无机和 有机化学课程，哈利B。灰度 加州理工学院将调查这些因素 控制生物体内的远程电子转移 系统.这些研究将有助于更好地了解 生命过程中的生化氧化还原机制。 研究了电子转移速率对给体的依赖性， 受体分离和反应驱动力（吉布斯自由能 能源）将在抹香鲸的几个衍生物中进行研究 肌红蛋白和马心细胞色素C。一种方法将是 用四胺修饰表面组氨酸， 钌吡啶鎓络合物，其将允许引入 有机受体部分在四个明确定义的位置上， 肌红蛋白表面。半合成程序将用于 将有机受体置于细胞色素c内的-82位 （苯丙氨酸-82将被氟-和氰基-苯基-取代， 丙氨酸）。复合驱动力/变距电子 将在改性后的 肌红蛋白光致电荷分离和电荷 锌卟啉/82位受体的复合反应 将研究细胞色素C衍生物。

In this project supported by the Inorganic, Bioinorganic and Organometallic Chemistry Program, Harry B. Gray of the California Institute of Technology will investigate the factors that control long-range electron transfer in biological systems. The studies will lead to a better understanding of the biochemical oxidation-reduction mechanisms in life processes. The dependence of the rate of electron transfer on donor- acceptor separation and reaction driving force (Gibbs free energy) will be studied in several derivatives of sperm whale myoglobin and horse heart cytochrome c. A methodology will be developed to modify surface histidines with tetraammine- ruthenium pyridinium complexes which will allow introduction of organic acceptor moieties in four well-defined positions on the surface of myoglobin. Semisynthetic procedures will be used to place organic acceptors at position-82 inside cytochrome c (phenylalanine-82 will be replaced by fluoro- and cyano-phenyl- alanines). Combined driving force/distance-variation electron transfer experiments will be carried out on the modified myoglobins. Photoinduced charge separation and charge recombination reactions in zinc porphyrin/position-82-acceptor cytochrome c derivatives will be investigated.