DYNAMICS IN ENZYME ACTION

本计划项目建议书涉及对以下角色的说明 多肽链动力学在催化机理中的作用 通过酶。该提案的总体目标是探索这一假说 多肽链动力学强烈影响局部相互作用 它介导酶的作用，可能是一个基本因素，允许 实现高流失率以及精致的专门性 反应。计划项目分为4个项目，都很紧密 着眼于这一长远目标，与彼此紧密相连。两个非常 不同的酶系统，二氢叶酸还原酶(DHFR)和一种金属... β-内酰胺酶，可能被选为深入研究的对象，希望 对于这两个系统所获得的结果可以用以下方面来概括 提案的指导性假设。前两个项目涉及 用实验手段确定多肽链动力学使用 核磁共振松弛等方法。项目1(P.E.Wright，P.I.)将专注于 用核磁共振松弛等方法对动力学进行了研究。项目1(体育 Wright，P.I.)将重点介绍DHFR在二元和三元体系中的动力学 与底物、抑制剂和辅因子的络合物以及对突变体的影响 在初步核磁共振动力学的基础上专门设计的 测量。类似的协议最终将在项目2中遵循 (H.J.Dyson，P.I.)金属β-内酰胺酶。这方面的初步目标 项目将涉及共振分配和与结构的关联， 结合对15N和13C弛豫的动力学和 从酰胺质子氢交换率。项目3(S.J.本科维奇，P.I.) 将利用项目1和项目2中提供的信息来设计场地- 这两种酶的定向突变体和抑制剂。此信息 除了对酶至关重要外，DHFR对于 抗癌治疗和金属β-内酰胺酶，因为它是主要的 病原菌中抗生素耐药性的成分。项目4(地区检察官 Case，P.1，C.L.Brooks，III，Co-P.I.)提供了必要的理论基础 这是工程的基础。基于项目中提供的信息 1、2和3，项目4将尝试对一致的反应路径进行建模 具有结构、动态和动力学信息，提供了潜在的 为了从根本上理解原子和原子的反应机制 电子水准仪。这些项目共同构成了一项集中努力，以 了解酶催化，结合动力学的新概念 多肽很可能是一种不可或缺的重要成分 整个过程。

This Program Project proposal concerns the elucidation of the role of polypeptide chain dynamics in the mechanism in the mechanism of catalysis by enzymes. The overall goal of the proposal is to explore the hypothesis that polypeptide chain dynamics strongly influence the local interactions that mediate enzyme action, and may be an essential factor that allows to achieve high turnover rates as well as exquisite specificity in their reactions. The Program Project is divided into 4 projects, all tightly focused on this long-term goal, and closely tied to each other. Two very different enzyme systems, dihydrofolate reductase (DHFR) and a metallo- beta-lactamase, may have been chosen for intensive study, in the hope that results obtained for the two systems may be generalizable in terms of the guiding hypothesis of the proposal. The first two projects are concerned with experimental measures to determine polypeptide chain dynamics using NMR relaxation and other methods. Project 1 (P.E. Wright, P.I.) will focus on the dynamics using NMR relaxation and other methods. Project 1 (P.E. Wright, P.I.) will focus on the dynamics of DHFR in binary and ternary complexes with substrates, inhibitors and cofactors, and on mutants specifically designed on the basis of preliminary NMR dynamics measurements. A similar protocol will ultimately be followed in Project 2 (H,J. Dyson, P.I.) for the metallo-beta-lactamase. Initial goals for this project will involve resonance assignment and correlation with structure, together with estimates of the dynamics from 15N and 13C relaxation and from amide proton hydrogen exchange rates. Project 3 (S.J. Benkovic, P.I.) will utilize the information provided in Projects 1 and 2 to design site- directed mutants and inhibitors for the two enzymes. This information besides being vital for the enzymes are important drug targets, DHFR for anti-cancer therapy and the metallo-beta-lactamase because it is a major component of antibiotic resistance in pathogenic bacteria. Project 4 (D.A. Case, P.1., C.L. Brooks, III, Co-P.I.) provides the essential theoretical underpinning for the project. Based on information available from Projects 1, 2 and 3, Project 4 will attempt to model reaction pathways consistent with structural, dynamic and kinetic information, providing the potential for a fundamental understanding of reaction mechanisms at an atomic and electronic level. Together, these projects constitute a focused effort to understand enzyme catalysis, incorporating the novel idea that dynamics of the polypeptide may well be an integral and important component of the entire process.