PHOTOBIOLOGY OF RHODOPSIN, BACTERIORHODOPSIN & VIODOPSIN

视紫红质、细菌视紫红质的光生物学

• 批准号: 6164773
• 负责人: ROBERT Richards BIRGE
• 金额: $ 19.55万
• 依托单位: UNIVERSITY OF CONNECTICUT STORRS
• 依托单位国家: 美国
• 财政年份: 1988
• 资助国家: 美国
• 起止时间: 1988-08-01 至 2002-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6164773
• 关键词: Xenopus; analog; bacteriorhodopsins; biophysics; calorimetry; cations; chemical substitution; chromophore; infrared spectrometry; interferometry; microwave spectrometry; molecular dynamics; molecular site; photochemistry; photoelectron spectrometry; protein structure; quantum chemistry; rhodopsin; site directed mutagenesis; visual pigments

DESCRIPTION: The nature of the chromophore binding sites and the primary photochemical events of rhodopsin, bacteriorhodopsin and the Xenopus violet cone pigment, viodopsin, will be studied by using spectroscopic and theoretical techniques. The goals are to understand the photophysical properties of the bound chromophores. The principal spectroscopic methods to be used in these studies include two-photon spectroscopy, Stark effect spectroscopy, Fourier transform infra-red spectroscopy, microwave spectroscopy, and pulsed laser photocalorimetry. The principal chemical studies to be undertaken include organic cation and chromophore analog substitutions, as well as site directed mutagenesis. The theoretical methods include semiempirical molecular orbital theory and molecular dynamics theory. The goal is to combine experiment and theory in a synergistic program which enhances both. In addition to the more global goals outlined above, Dr. Birge will seek to answer the following specific questions: (1) What is the principal mechanism of wavelength modulation in the blue and violet cones? (2) Where are the cation binding sites in bacteriorhodopsin, and how do these sites mediate the properties of the bound chromophore? (3) Is there a chloride binding site in viodopsin, and what impact does this site have on the photophysical properties of the chromophore? (4) What are the molecular origins of energy storage in the primary events of these three proteins? (5) What is the principal molecular mechanism of dark noise in vertebrate and invertebrate vision? (6) What are the molecular origins of the unusual photochemical properties of the 4-keto retinal bacteriorhodopsin analog? (7) Can one improve the accuracy of the MNDO-PSDCI semi-empirical molecular orbital theory by using ab-initio effective Hamiltonian parameterizaion?

描述：发色团结合位点的性质和主要 视紫红质、细菌视紫红质和爪蟾紫的光化学事件 视锥色素，viodopsin，将通过使用光谱和 理论技术。 目标是了解光物理 结合发色团的特性。 主要光谱方法 这些研究中使用的包括双光子光谱、斯塔克效应 光谱学、傅里叶变换红外光谱学、微波 光谱学和脉冲激光光量热法。 主要化学品 即将进行的研究包括有机阳离子和发色团类似物 取代以及定点诱变。 理论 方法包括半经验分子轨道理论和分子 动力学理论。 目标是将实验和理论结合起来 增强两者的协同计划。 除了更全球化的 对于上述目标，Birge 博士将寻求回答以下具体问题 问题： (1) 波长调制的主要机制是什么？ 蓝色和紫色视锥细胞？ (2) 阳离子结合位点在哪里 细菌视紫红质，以及这些位点如何介导细菌视紫红质的特性 结合发色团？ (3)维紫红质中是否存在氯离子结合位点，以及 该站点对光物理特性有什么影响 发色团？ (4) 储能的分子起源是什么？ 这三种蛋白质的主要事件是什么？ (5) 主分子是什么 脊椎动物和无脊椎动物视觉中的暗噪声机制？ (6) 什么是 4-酮不寻常光化学性质的分子起源 视网膜细菌视紫红质类似物？ (7)能否提高测量精度 MNDO-PSDCI 使用从头算的半经验分子轨道理论 有效的哈密顿参数化？