Primary Processes in Photosystem I

光系统 I 中的主要过程

• 批准号: 0091250
• 负责人: Robert Blankenship
• 金额: $ 55万
• 依托单位: Arizona State University
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2001
• 资助国家: 美国
• 起止时间: 2001-03-01 至 2007-02-28
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0091250&HistoricalAwards=false
• 关键词: Primary; Processes; Photosystem

Photosynthetic organisms use a twofold strategy to capture and store solar energy. An antenna system first collects light and then transfers the energy to an electron transfer system that converts electronic excitation into redox energy that can be used for cell growth. In most photosynthetic systems, the antenna and electron transfer functions are located on separable complexes and can be studied independently. However, in Photosystem I of oxygenic photosynthetic organisms, the antenna and electron transfer functions are fused into a single large complex that serves both functions. Experiments are proposed to improve our current fragmentary understanding of the energy trapping processes, primary photochemistry and early secondary electron transfer reactions in this important class of photosynthetic reaction centers. Overall goals of the work are to understand the coupling of the antenna system to the electron transfer system and the pathway of the early electron transfer processes. Specific experiments in this project include: 1) Studies on Photosystem I mutants in the quinone and pigment binding regions, 2) Separation of the Photosystem I reaction center complex into antenna and electron transfer domains using protein engineering and 3) Analysis of Photosystem I energy trapping and electron transfer in a newly-discovered chlorophyll d-containing organism, Acaryochloris marina. This project will increase our understanding of how plants and other photosynthetic organisms convert the energy of sunlight into chemical energy. The process of photosynthesis supplies all of our food and most of our energy needs. This project is designed to give detailed knowledge of the chemical mechanism of this essential biological process.

光合生物使用双重策略来捕获和储存太阳能。天线系统首先收集光，然后将能量转移到电子转移系统，该电子转移系统将电子激发转化为可用于细胞生长的氧化还原能量。在大多数光合系统中，天线和电子传递函数位于可分离的复合物上，可以独立研究。然而，在光合生物的光系统I中，天线和电子传递功能融合成一个单一的大复合体，同时提供两种功能。实验提出，以提高我们目前零碎的理解的能量捕获过程中，初级光化学和早期的二次电子转移反应在这一类重要的光合反应中心。本工作的总体目标是了解天线系统与电子转移系统的耦合以及早期电子转移过程的途径。 本项目的具体实验包括：1）醌和色素结合区的光系统I突变体研究; 2）利用蛋白质工程将光系统I反应中心复合体分离为触角和电子传递结构域; 3）分析新发现的含叶绿素d生物Acaryochloris marina中光系统I的能量捕获和电子传递。 这个项目将增加我们对植物和其他光合生物如何将太阳能转化为化学能的理解。光合作用的过程提供了我们所有的食物和大部分的能量需求。该项目旨在详细了解这一基本生物过程的化学机制。