MECHANISM OF RESPIRATION AND ENERGY TRANSDUCTION

细胞色素Bc1复合体是一种低聚膜酶， 参与真核生物中与呼吸有关的能量转导 细胞，类似地参与呼吸作用、光合作用电子 细菌的迁移、反硝化、固氮和硫代谢 细菌。了解细胞色素Bc1的分子基础 复合体执行这种能量传递对于理解 细胞能量学。 这项研究的目的是了解细胞内的亚基是如何 细胞色素Bc1复合体参与能量转导活动 并阐明该低聚物通过何种途径 酶被组装到线粒体膜内。 实验的基础是细胞色素Bc1 复合体通过质子动力Q循环机制运行，并且 这种酶的线粒体型含有多个多余的 在该机制中没有明显作用的亚基。这个 实验旨在回答三个问题。 1.Bc1复合体的铁-硫蛋白亚基如何催化 Q循环中需要的泛喹酚的发散氧化 机械装置？ 2.各编外单位有何作用？ 线粒体Bc1复合体？ 3.10或11事件的途径或顺序是什么 这种酶复合体的亚基组装成内部 线粒体膜？ 我们正在使用遗传学和生物化学方法来阐明答案。 在酿酒酵母中对这些问题的回答。这些方法包括 Bc1亚基基因的分离和操纵 络合物中电子转移反应的表征 对亚基进行选定的修改后的复杂性，确定 络合物组装的中间步骤，以及纯化和 部分组装亚络合物的表征及其可能的影响因素 参与了建筑群的组装。

The cytochrome bc1 complex is an oligomeric membrane enzyme which participates in energy transduction linked to respiration in eukaryotic cells, and similarly participates in respiration, photosynthetic electron transfer, denitrification, nitrogen fixation, and sulfur metabolism in bacteria. Understanding the molecular basis of how the cytochrome bc1 complex performs this energy transduction is essential to understanding cellular energetics. The objectives of this research are to understand how the subunits of the cytochrome bc1 complex participate in the energy transduction activities of the complex, and to elucidate the pathway by which this oligomeric enzyme is assembled into the inner mitochondrial membrane. The experimentation is based on the rationale that the cytochrome bc1 complex operates by a protonmotive Q cycle mechanism, and that the mitochondrial forms of this enzyme contain multiple supernumerary subunits which have no obvious function in that mechanism. The experimentation is intended to answer three questions. 1. How does the iron-sulfur protein subunit of the bc1 complex catalyze the divergent oxidation of ubiquinol which is required in the Q cycle mechanism? 2. What are the functions of the supernumerary subunits in the mitochondrial bc1 complexes? 3. What is the pathway or sequence of events by which the 10 or 11 subunits of this enzyme complex are assembled into the inner mitochondrial membrane? We are using genetics and biochemical approaches to elucidate the answers to these questions in Saccharomyces cerevisiae. The approaches include isolation and manipulation of genes for individual subunits of the bc1 complex, characterization of electron transfer reactions within the complex following selected modifications to subunits, identification of intermediate steps in the assembly of the complex, and purification and characterization of partially assembled subcomplexes and possible factors involved in assembly of the complex.