STRUCTURE & FUNCTION OF PHOTOSYNTHETIC REACTION CENTERS

结构

• 批准号: 2444424
• 负责人: GEORGE FEHER
• 金额: $ 41.55万
• 依托单位: UNIVERSITY OF CALIFORNIA, SAN DIEGO
• 依托单位国家: 美国
• 财政年份: 1976
• 资助国家: 美国
• 起止时间: 1976-05-10 至 2000-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/2444424
• 关键词: Chlamydomonas; X ray crystallography; atomic force microscopy; bioenergetics; computer simulation; crystallization; cytochrome c; dielectric property; electron density; electron nuclear double resonance spectroscopy; electron spin resonance spectroscopy; electron transport; hydrogen bond; ionic bond; lysozyme; molecular dynamics; mutant; oxidation reduction reaction; photosynthesis; photosynthetic bacteria; photosynthetic reaction centers; photosystem; protein structure function; quinones; structural biology

DESCRIPTION: In the broadest sense, Dr. Feher's objective is to understand biological processes and phenomena in terms of physical mechanisms; i.e., on a molecular level. The main problem addressed in this proposal deals with the conversion of electromagnetic energy into chemical energy; i.e., photosynthesis. This is one of the most basic processes in biology; all energy of the living world is derived from it. At the heart of the photosynthetic process is a membrane bound protein-pigment complex called the reaction center (RC). Dr. Feher studies the structure and function of the RC and the secondary donor, cytochrome c2. The mechanisms of electron and proton transfers that take place in the RC are of general interest and importance in all living systems. For instance, the processes that occur in mitochondria (e.g. in mammalian cells) can be viewed as the reverse process of photosynthesis utilizing similar mechanisms. Furthermore, the RC, being the best characterized membrane bound protein, serves as an excellent model for other membrane proteins that perform important functions in a variety of biochemical processes. The necessity of having single crystals to determine structures led Dr. Feher to a basic investigation of the crystallization mechanisms of macromolecules. Crystallization, in addition to being of great practical importance, serves as an example of molecular association (recognition); a ubiquitous phenomenon throughout the living world. The fields and methodologies involved in this work are interdisciplinary, ranging from physics to chemistry and molecular biology. The techniques used are: X-ray crystallography, electron and atomic force microscopy, optical and magnetic (EPR/ENDOR) spectroscopy, computational (e.g. Monte Carlo simulations), protein chemistry and recombinant DNA techniques. The specific problems addressed are: The three-dimensional structure of native and mutant RCs from the photosynthetic bacterium Rb. sphaeroides, the structures of cytochrome c2, the RC-cyt c2 complex, the RC from photosystem II of green plants; electron transfers in RCs, calculation of electrostatic energies in RCs and the mechanism of crystallization of biological macromolecules.

描述：从最广泛的意义上来说，Feher 博士的目标是了解 物理机制方面的生物过程和现象；即，在 分子水平。 该提案解决的主要问题涉及 将电磁能转化为化学能； IE。， 光合作用。 这是生物学最基本的过程之一；全部 生命世界的能量来源于它。 在的心脏 光合作用过程是一种膜结合的蛋白质-色素复合物，称为 反应中心（RC）。 Feher 博士研究了结构和功能 RC 和第二供体细胞色素 c2。 电子的机制 RC 中发生的质子转移受到普遍关注，并且 在所有生命系统中的重要性。 例如，发生在 线粒体（例如在哺乳动物细胞中）可以被视为相反的过程 利用类似的机制进行光合作用。 此外，RC， 特征最好的膜结合蛋白，作为一个优秀的模型 对于在多种中发挥重要功能的其他膜蛋白 生化过程。 需要使用单晶来确定结构，这使得 Dr. Feher 对结晶机制的基本研究 大分子。 结晶，除了具有很大的实用性 重要性，作为分子关联（识别）的一个例子；一个 生命世界中普遍存在的现象。 这项工作涉及的领域和方法是跨学科的， 范围从物理学到化学和分子生物学。 技巧 使用的是：X射线晶体学、电子和原子力显微镜、 光和磁（EPR/ENDOR）光谱、计算（例如蒙特 卡罗模拟）、蛋白质化学和重组 DNA 技术。 解决的具体问题是： 的三维结构 来自光合细菌 Rb 的天然和突变 RC。球状体 细胞色素 c2、RC-cyt c2 复合物、来自光系统的 RC 的结构 二、绿色植物； RC 中的电子转移，静电计算 RCs的能量和生物结晶机制 大分子。