Residue Scale Characterization of Protein Structure Fluctuations

蛋白质结构波动的残留规模表征

• 批准号: 6706158
• 负责人: ROBIN Main HOCHSTRASSER
• 金额: $ 10.94万
• 依托单位: UNIVERSITY OF PENNSYLVANIA
• 依托单位国家: 美国
• 财政年份: 2003
• 资助国家: 美国
• 起止时间: 2003-08-01 至 2008-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6706158
• 关键词: biomaterials; calmodulin; cytochrome c; electric field; electrical property; electron transport; electronic spectra; gel; hydrogen bond; infrared spectrometry; ionic bond; molecular dynamics; photolysis; protein protein interaction; protein structure function; quantum chemistry; time resolved data; trehalose; vibration

Real time measurements of energy and angular fluctuations in peptides and proteins using ultrafast optical, stimulated IR echoes, 2D IR and single molecule spectroscopy are proposed to examine interactions and correlations between vibrational modes and their surroundings for isotopic selections of peptides and proteins. Time correlation functions for amide-I, amide-II, CH3 and amide-A groups selected by carbon, oxygen and deuterium isotopic replacement will be measured and modeled. The influence of electrostatics, solvent interactions and structural heterogeniety on delocalization of vibrational energy in peptides will be examined. IR photon echoes and dynamic 2D IR will allow characterization of the solvent related energy fluctuations of selected pieces of alpha helices, and evaluation of effects of charged residues and polar solvents from the vibrational dynamics, and fast hydrogen bond dissociation dynamics of water molecules (HDO) from ions nearby to proteins. The dynamics of cytochrome c at equilibrium and following CO photolysis will be examined by 2D IR of 18O, 13C and deuterium labeled residues to determine the fluctuations in the Met (80) residue and Phe (82). Infrared transitions of optically excited aggregates will be examined and theoretical models for amide IR spectra in secondary structures will be developed. Single molecule experiments based on spectra, lifetime and photon arrival time distributions will address equilibrium fluctuations of the glass and hydrogel encapsulated calcium calmodulin peptide complex via Nile Red fluorecence quenching, LH2 complexes, trehalose protein interactions and the distributions of rates of energy transfer in donor and acceptor labeled peptides immobilized in glasses and gels near the glass transitions.

提出了利用超快光学、受激红外回波、二维红外和单分子光谱对肽和蛋白质的能量和角涨落进行真实的实时测量，以研究肽和蛋白质的同位素选择中振动模式与其周围环境之间的相互作用和相关性。将测量并建模通过碳、氧和氘同位素置换选择的酰胺-I、酰胺-II、CH 3和酰胺-A基团的时间相关函数。研究了静电、溶剂相互作用和结构异质性对肽振动能离域的影响。IR光子回波和动态2D IR将允许表征所选α螺旋片段的溶剂相关能量波动，并评估带电残基和极性残基的影响。 溶剂的振动动力学，以及水分子（HDO）从附近的离子到蛋白质的快速氢键解离动力学。将通过18 O、13 C和氘标记残基的2D IR来检查细胞色素c在平衡时和CO光解后的动力学，以确定Met（80）残基和Phe（82）的波动。光学激发聚集体的红外跃迁将被检查和二级结构中酰胺红外光谱的理论模型将被开发。基于光谱、寿命和光子到达时间分布的单分子实验将通过尼罗红荧光猝灭、LH 2复合物、海藻糖蛋白相互作用和固定在玻璃和凝胶中的供体和受体标记肽在玻璃转变附近的能量转移速率分布来解决玻璃和水凝胶封装的钙钙调蛋白肽复合物的平衡波动。