IRON-SULFUR PROTEINS AS BOUND ELECTRON CARRIERS

铁硫蛋白作为结合电子载体

• 批准号: 3270087
• 负责人: RICHARD MALKIN
• 金额: $ 14.55万
• 依托单位: UNIVERSITY OF CALIFORNIA BERKELEY
• 依托单位国家: 美国
• 财政年份: 1977
• 资助国家: 美国
• 起止时间: 1977-07-01 至 1996-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/3270087
• 关键词: Bacillus subtilis; Chlamydomonas; Escherichia coli; Rhodopseudomonas; binding proteins; bioenergetics; biological signal transduction; chloroplasts; complementary DNA; cytochrome b; cytochrome c; electron spin resonance spectroscopy; electron transport; enzyme complex; enzyme mechanism; hemoprotein structure; iron sulfur protein; molecular cloning; photosynthetic bacteria; photosystem; protein structure function; quinones; site directed mutagenesis; transport proteins

Cytochrome bc1 and b6f complexes act in energy-transducing membranes to create a proton gradient that is used for the synthesis of ATP. The energy required to establish this- gradient comes from an oxidation- reduction process in which a quinol is oxidized and a high-potential electron acceptor is reduced. All cytochrome complexes contain three electron transfer proteins: a b-type cytochrome, a c-type cytochrome and a high potential 2Fe-2S Rieske Fe-S protein. This project focuses on the structure and function of several of these electron transfer proteins in reactions catalyzed by the cytochrome b6f complex as well as considering possible roles for other protein subunits that have recently been found in this complex. The approach taken in the project is to employ a combination of molecular biological techniques in conjunction with biochemical and biophysical analyses. Thus, the use of cloned genes for cytochrome f and the Rieske Fe-S protein will allow for site-directed mutagenesis of amino acids proposed to play specific roles in the function and structure of these proteins. The use of the green alga, Chlamydomonas, will facilitate these experiments since this organism can be grown non-photosynthetically to maintain mutants and is transformable. In addition to these studies, an analysis of cytochrome complexes from the green sulfur bacterium, Chlorobium, and the heterotrophic bacterium, Bacillus, will be carried out in order to define if these organisms contain cytochrome bc1 or b6f-type complexes. These studies will provide detailed evidence on the role of the Rieske iron-sulfur protein and other electron carriers in the catalytic reactions of the cytochrome b6f complex.

细胞色素bc 1和b6 f复合物在能量转导膜中起作用， 产生一个质子梯度，用于合成ATP。 的 建立这种梯度所需的能量来自氧化， 氧化醌醇的还原过程， 电子受体被还原。 所有的细胞色素复合物都含有三个 电子转移蛋白：b型细胞色素，c型细胞色素和 一种高电位2Fe-2S Rieske Fe-S蛋白。 该项目的重点是 这些电子转移蛋白中几种在 由细胞色素b6 f复合物催化的反应以及考虑 最近发现的其他蛋白质亚基的可能作用 在这个复杂的。 该项目采取的方法是采用 结合分子生物学技术， 生物化学和生物物理分析。 因此，使用克隆的基因用于 细胞色素f和Rieske Fe-S蛋白将允许定点 突变的氨基酸提出发挥特定的作用， 这些蛋白质的功能和结构。 绿色颜料的使用， 衣原体，将有助于这些实验，因为这种生物体可以 非光合作用生长以保持突变体并且是可转化的。 除了这些研究之外，还分析了来自 绿色硫细菌绿菌属和异养细菌， 将进行芽孢杆菌，以确定这些微生物是否 含有细胞色素Bc 1或B6 F型复合物。 这些研究将提供 关于Rieske铁硫蛋白和其他蛋白质作用的详细证据 细胞色素b6 f催化反应中的电子载体 复杂.