TRIPLET STATE PHOTOPHYSICS OF TRYPTOPHAN & TRYPTOPHAN ANALOGS

色氨酸的三重态光物理学

• 批准号: 6120156
• 负责人: R D LUDESCHER
• 金额: $ 0.05万
• 依托单位: UNIVERSITY OF PENNSYLVANIA
• 依托单位国家: 美国
• 财政年份: 1999
• 资助国家: 美国
• 起止时间: 1999-08-01 至 2000-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6120156
• 关键词: biological products; biomedical resource; proteins

Tryptophan phosphorescence has been used for over 20 years to study the conformation and flexibility of proteins under physiological conditions. The basis for this research has been the extraordinary sensitivity of the tryptophan triplet state to quenching by molecular collisions (protein flexibility). The triplet state photophysics of tryptophan and its analogs is inadequately understood; little is known of the actual physical mechanism by which collisions quench the triplet state and almost nothing is known about the triplet state photophysics and non-radiative decay of tryptophan analogs (which can be incorporated into proteins in vivo to generate spectrally enhanced proteins). This project will investigate the triplet state photophysics of trp and trp analogs at room temperature in glassy sugar matrixes and the effect of temperature and viscosity on these properties, additional studies will assay the effect of deuterium substitution on non-radiative decay of try ptophan to evaluate the influence of C-H stretch/bending modes on promoting the T to S transition. Measurements of quantum yields for fluorescence, triplet state formation, and phosphorescence will be combined with lifetime measurements to generate a complete photophysical characterization of the excited state photophysics of this important class of biological chromophores. Detailed comparison of the photophysical behavior in rigid (glassy sugar) and mobile (viscous solution) environments will allow evaluation of the quenching rate constant due to collisions for tryptophan and each of the analogs.

色氨酸磷光的应用已超过 20 年 研究蛋白质在生理条件下的构象和柔韧性 状况。 这项研究的基础是非凡的 色氨酸三重态对分子猝灭的敏感性 碰撞（蛋白质灵活性）。 三重态光物理 对色氨酸及其类似物的了解还不够；鲜为人知 碰撞淬灭的实际物理机制 三重态并且对三重态几乎一无所知 色氨酸类似物的光物理学和非辐射衰变（可以 被整合到体内蛋白质中以产生光谱增强的 蛋白质）。 该项目将研究三重态 室温下玻璃态色氨酸和色氨酸类似物的光物理学 糖基质以及温度和粘度对这些基质的影响 性质，额外的研究将测定氘的影响 替代色氨酸的非辐射衰变来评估 C-H 拉伸/弯曲模式对推动 T 到 S 的影响 过渡。 荧光、三重态量子产率的测量 状态形成，磷光将与寿命结合起来 测量以生成完整的光物理特征 这一类重要生物的激发态光物理学 发色团。 光物理行为的详细比较 刚性（玻璃糖）和移动（粘性溶液）环境将 允许评估由于碰撞而导致的淬火速率常数 色氨酸和每种类似物。