Nantes Iseli L, Kawai Cintia, Pessoto Felipe S, Mugnol Katia C U
Centro Interdisciplinar de Investigação Bioquímica CIIB, Universidade de Mogi das Cruzes, S.P., Brazil.
Methods Mol Biol. 2010;606:147-65. doi: 10.1007/978-1-60761-447-0_12.
Important findings regarding the structure and function of respiratory cytochromes have been made from the study of these hemeproteins associated to liposomes. These studies contributed to the comprehension of the biological role of these proteins in the electron transfer process, the regulatory mechanisms, the energy transduction mechanisms, the protein sites that interact with mitochondrial membranes and the role played by the non-redox subunits present in the protein complexes of the respiratory chain of eukaryotes. In this chapter, the protocols developed to study cytochrome bc (1) activity in liposomes and the binding of cytochrome c to lipid bilayers is presented . The former protocol was developed to study the mechanism of energy transduction related to the topology of the components of bc (1) complex in the mitochondrial membrane. These studies were done with purified cytochrome bc (1) complexes reconstituted into potassium-loaded vesicles. The latter protocol was developed to study the influence of pH, DeltapH, and DeltaPsi on the interaction of cytochrome c with liposomes that mimic the inner mitochondrial membrane.
通过对这些与脂质体相关的血红素蛋白的研究，已获得了有关呼吸细胞色素结构和功能的重要发现。这些研究有助于理解这些蛋白质在电子传递过程中的生物学作用、调节机制、能量转导机制、与线粒体膜相互作用的蛋白质位点以及真核生物呼吸链蛋白质复合物中存在的非氧化还原亚基所起的作用。在本章中，将介绍用于研究脂质体中细胞色素bc(1)活性以及细胞色素c与脂质双层结合的实验方案。前一个实验方案是为了研究与线粒体膜中bc(1)复合物各组分拓扑结构相关的能量转导机制而制定的。这些研究是用重构到加载钾的囊泡中的纯化细胞色素bc(1)复合物进行的。后一个实验方案是为了研究pH、ΔpH和ΔΨ对细胞色素c与模拟线粒体内膜的脂质体相互作用的影响而制定的。
