Structure and Function of Carotenoids

类胡萝卜素的结构和功能

• 批准号: 7118687
• 负责人: Harry A Frank
• 金额: $ 21.68万
• 依托单位: UNIVERSITY OF CONNECTICUT STORRS
• 依托单位国家: 美国
• 财政年份: 1987
• 资助国家: 美国
• 起止时间: 1987-09-01 至 2009-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7118687
• 关键词: Raman spectrometry; X ray crystallography; bacterial pigment; bacterial proteins; carotenoids; chemical structure function; cis trans isomerization; computer simulation; crystallization; electron spin resonance spectroscopy; intermolecular interaction; model design /development; molecular dynamics; nuclear magnetic resonance spectroscopy; optics; photochemistry; photoprotection; photosynthetic bacteria; photosynthetic reaction centers; physical model; protein purification; site directed mutagenesis; structural biology; time resolved data

DESCRIPTION (provided by applicant): The objective of the research contained in this application is to elucidate how the structural features of carotenoids determine their photochemical properties and biological functions in vivo. Particular attention will be given to the roles of carotenoids in light-harvesting and photo-protection, which are essential for the survival of photosynthetic organisms. The systems to be studied include carotenoids in vitro and in pigment/protein complexes, obtained from different species of algae and prokaryotic and purple photosynthetic bacteria. These systems will be used, because reaction centers, and antenna carotenoid-containing pigment-protein complexes prepared from them, can be purified, pigment-reconstituted, pigment-exchanged, crystallized, and genetically altered via site-directed mutagenesis. X-ray crystallography, nuclear magnetic resonance, and resonance Raman spectroscopy will be used as direct structural probes. Kinetic and quantum mechanical models of the photochemical behavior of carotenoids will be tested using steady state absorption, fluorescence, fluorescence excitation, electron paramagnetic resonance, two-photon, and ultrafast-transient absorption spectroscopy. These experiments will be augmented by theoretical quantum mechanical computations, to allow a quantitative correlation of structure with spectroscopic observables and biological function. The specific aims of this proposal are: (1) To examine the structures of carotenoids in photosynthetic pigment-protein complexes; (2) To explore the relationships between the carotenoid structures and their spectroscopic properties; and (3) To determine the relationships between the carotenoid structures and the mechanisms by which they function in vivo. Several preliminary studies have already been carried out by us in support of the methods we propose to employ.

描述（由申请人提供）：本申请中包含的研究目的是阐明类胡萝卜素的结构特征如何决定其体内光化学特性和生物学功能。将特别注意类胡萝卜素在光收集和光保护方面的作用，这是光合生物生存所必需的。待研究的系统包括从不同种类的藻类、原核生物和紫色光合细菌中获得的体外和色素/蛋白质复合物中的类胡萝卜素。这些系统将被使用，因为反应中心和由它们制备的天线类胡萝卜素色素-蛋白质复合物可以被纯化、色素重组、色素交换、结晶和通过位点定向诱变进行基因改变。x射线晶体学、核磁共振和共振拉曼光谱将被用作直接的结构探针。类胡萝卜素光化学行为的动力学和量子力学模型将使用稳态吸收、荧光、荧光激发、电子顺磁共振、双光子和超快瞬态吸收光谱进行测试。这些实验将通过理论量子力学计算来增强，以允许结构与光谱观测和生物功能的定量关联。本提案的具体目的是：(1)研究光合色素-蛋白质复合物中类胡萝卜素的结构；(2)探索类胡萝卜素结构与其光谱性质的关系；(3)确定类胡萝卜素结构及其在体内发挥作用的机制之间的关系。我们已经进行了几项初步研究，以支持我们建议采用的方法。