VIBRATIONAL AND DYNAMICAL STUDIES OF ENZYMES

描述：（由摘要修改）酶催化的动力学 反应将在分子水平上进行研究。拉曼和红外差 光谱学将用于静态测量和动态拉曼和红外 测量将使用亚毫秒时间分辨率，低至10 ns 分辨率，在某些情况下，必要时可达到50 ps， 动态测量重点将放在两类酶：NAD（P） 连接的酶和磷酰基转移酶，两者都靶向 抗菌和抗癌药物。将特别注意 研究二氢叶酸还原酶，以了解N5的pKa是如何改变的。 将二氢叶酸底物结合到E.大肠杆菌的酶升高了四个单位 与解决方案相比。这将通过测量突变蛋白来探索， 不同的二氢叶酸还原酶同工酶和相关的蛋白质， 叶酸家族（二氢新蝶呤醛缩酶）。详细的静电计算 也将被用来理解这个系统。此外，c-Harvey ras p21 蛋白质，其含有G蛋白的必需GTdR核心， 耶尔森菌酶，蛋白质酪氨酸磷酸酶的一个例子，将进行研究。 磷酸盐的基态和过渡态结构 将研究天然蛋白质和一系列突变体的复合物。的 配体与蛋白质结合的动力学和柔性的 将通过检查与乳酸脱氢酶的配体结合来探测环， 其他蛋白质和环运动将在乳酸脱氢酶中进行检查， 耶尔森氏菌酶等系统。

DESCRIPTION: (modified from abstract) The dynamics of enzymatic catalysis reactions will be studied at the molecular level. Raman and IR difference spectroscopies will be used for static measurements and kinetic Raman and IR measurements will be used with submillisecond time resolution, down to 10 ns resolution in some cases, with capabilities to 50 ps when necessary, for dynamic measurements. Emphasis will be on two classes of enzymes: the NAD(P) linked enzymes and the phosphoryl transfer enzymes, both targets for antibacterial and anti-cancer pharmaceuticals. Particular attention will be paid to studying dihydrofolate reductase to understand how the pKa of N5 of the bound dihydrofolate substrate to the E. coli enzyme is raised four units compared to solution. This will be probed by measurements of mutant proteins of different dihydrofolate reductase isoenzymes and of a related protein of the folate family (dihydroneopterin aldolase). Detailed electrostatic calculations will also be used to understand this system. In addition, the c-Harvey ras p21 protein, which contains the essential GTPase core of G-proteins, and the Yersinia enzyme, an example of protein-tyrosine phosphatases, will be studied. The structures of phosphate ground state and the transition state analog complexes of the native protein and a series of mutants will be studied. The kinetics of the binding of ligands to proteins and the motions of flexible loops will be probed by examining ligand binding to lactate dehydrogenase and other proteins, and loop motions will be examined in lactate dehydrogenase, the Yersinia enzyme, and other systems.