Mechanisms of Enzyme Catalysis

描述（由申请人提供）：该项目的目标是确定 PEP 变位酶/异柠檬酸裂解酶和 4-羟基苯甲酰基-CoA 硫酯酶家族选定成员的结构、功能和作用机制。该信息将用于将活性位点结构与催化联系起来，从而识别标记，这些标记可用于为每个酶家族内的所有未知蛋白质分配功能。预计从这些努力中出现的新的蛋白质功能和代谢途径将与活性位点结构的确定一起，作为药物发现的基础。最后，从拟议的研究中，首席研究员和她的团队将深入了解介导以两个酶家族为代表的不同化学反应的酶的催化机制，以及这些催化机制如何从祖先活性位点模板演变而来。具体目标 1-4 将解决 PEP 变位酶/异柠檬酸裂解酶家族四个成员的结构、功能和催化机制：洋葱伯克霍尔德氏菌的磷酸丙酮酸水解酶、5, 1 0-亚甲基四氢叶酸：铜绿假单胞菌的 3-甲基-2-氧代丁酸羟甲基转移酶、与康乃馨花瓣死亡相关的蛋白质和蛋白质结核分枝杆菌 (Rv1998c) 中存在未知功能。具体目标 5-9 将讨论 4-羟基苯甲酰基-CoA 硫酯酶家族的五个成员的结构、功能和催化机制：4-羟基苯甲酰基-CoA 硫酯酶、流感嗜血杆菌 Tol-pal 途径的 YgbC 酶、大肠杆菌苯乙酸分解代谢途径的 P76084 未知蛋白、芽孢杆菌的 BH1 997 未知蛋白halodurans 上龙胆酸途径和铜绿假单胞菌 PA551 9 与人长链酰基辅酶 A 硫酯酶同源

DESCRIPTION (provided by applicant): The goal of this project is to determine structure, function, and mechanism of action of selected members of the PEP mutase/isocitrate lyase and 4-hydroxybenzoyl-CoA thioesterase enzyme families. This information will be used to relate active site structure to catalysis, and thereby identify markers, which can be applied in the assignment of function to all unknown proteins within each enzyme family. The novel protein functions and metabolic pathways that are anticipated to emerge from these efforts will, along with the active site structure determinations, serve as the foundation for drug discovery. Finally, from the proposed studies the principal investigator and her group will gain insight into the catalytic mechanisms of the enzymes mediating the diverse chemistries represented by the two enzyme families, and into how these catalytic mechanisms evolved from ancestral active site templates. Specific Aims 1-4 will address structure, function and catalytic mechanism in four members of the PEP mutase/ isocitrate lyase enzyme family: phosphonopyruvate hydrolase of Burkholderia cepacia, 5, 1 0-methylenetetrahydrofolate: 3-methyl-2-oxobutanoate hydroxymethyl transferase of Pseudomonas aeruginosa, a protein associated with petal death in carnation, and a protein of unknown function present in Mycobacterium tuberculosis (Rv1998c). Specific Aims 5-9 will address structure, function and catalytic mechanism in five members of the 4-hydroxybenzoyl-CoA thioesterase enzyme family: 4-hydroxybenzoyl-CoA thioesterase, the YgbC enzyme of the Haemophilus influenza Tol-pal Pathway, the P76084 unknown protein of the E.coli Phenylacetate Catabolic Pathway, the BH1 997 unknown protein of the Bacillus halodurans Upper Gentisate Pathway and the Pseudomonas aeruginosa PA551 9 homologue to the Human Long Chain Acyl-CoA Thioesterase