Primary Processes in Fe-S-Type Photosynthetic Reactions Centers

Fe-S型光合反应中心的初级过程

• 批准号: 9727607
• 负责人: Robert Blankenship
• 金额: $ 33.55万
• 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: 1998
• 资助国家: 美国
• 起止时间: 1998-01-01 至 2000-12-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9727607&HistoricalAwards=false
• 关键词: Primary; Processes; Fe; Type; Photosynthetic

9727607 Blankenship The objective of this research is to extend the current understanding of the energy trapping processes, primary photochemistry and early secondary electron transfer reactions in photosynthetic reaction centers that contain FeS centers as early electron acceptors. The particular systems that will be studied include reaction centers from the primitive anoxygenic organisms known as heliobacteria as well as Photosystem I of oxygenic photosynthetic organisms. One of the overall goals of the work is to correlate some of the pigments observed in spectroscopic studies with pigments observed in the recent X-ray structure of Photosystem I. Specific proposed experiments include, picosecond transient absorbance measurements in the blue spectral region in Photosystem I, studies on Photosystem I mutants in the quinone-binding region and the P700 binding region, dichroism experiments on Photosystem I and investigation of secondary electron transfer reactions in heliobacteria monitored using EPR and picosecond timescale transient absorbance spectroscopy. These experiments will give new insights into the energy trapping process in reaction centers that contain integral core antenna pigments and will help to identify and characterize some of the early electron acceptors in these systems, including chlorophylls, quinones and FeS centers. The goal of this work is to understand how plants and other photosynthetic organisms convert the energy of sunlight into chemical energy. This project is designed to give detailed knowledge of the chemical mechanism of energy storage in a class of photosynthetic complexes that is not well understood. Advances in understanding the basic scientific principles at work in this essential biological process may ultimately lead to the development of artificial energy storage systems. The artificial systems may decrease our dependence on fossil fuels and reduce emission of pullutants and greenhouse gases. Another possible benefit is the use of this knowledg e in the development of improved plants that will help meet our food and fiber needs. ***

9727607 Blankenship 这项研究的目的是扩展目前对包含 FeS 中心作为早期电子受体的光合反应中心的能量捕获过程、初级光化学和早期二次电子转移反应的理解。 将研究的特定系统包括来自称为日光杆菌的原始缺氧生物的反应中心以及含氧光合生物的光系统 I。 这项工作的总体目标之一是将光谱研究中观察到的一些颜料与光系统 I 最近的 X 射线结构中观察到的颜料相关联。具体提出的实验包括光系统 I 中蓝色光谱区域的皮秒瞬态吸光度测量，对醌结合区和 P700 结合区的光系统 I 突变体的研究，光系统 I 的二色性实验以及使用 EPR 和皮秒时间尺度监测的日光细菌二次电子转移反应的研究瞬态吸收光谱。 这些实验将为包含整体核心天线颜料的反应中心的能量捕获过程提供新的见解，并将有助于识别和表征这些系统中的一些早期电子受体，包括叶绿素、醌和FeS中心。 这项工作的目标是了解植物和其他光合生物如何将阳光的能量转化为化学能。 该项目旨在详细了解一类尚不清楚的光合复合物中能量储存的化学机制。 对这一重要生物过程中基本科学原理的理解的进步可能最终导致人工能量存储系统的发展。 人工系统可以减少我们对化石燃料的依赖，并减少污染物和温室气体的排放。 另一个可能的好处是利用这些知识来开发改良植物，这将有助于满足我们的食物和纤维需求。 ***