Protein Dynamics in Dihydrofolate Reductase Catalysis

二氢叶酸还原酶催化中的蛋白质动力学

• 批准号: 8697848
• 负责人: PETER Edwin WRIGHT
• 金额: $ 39.41万
• 依托单位: SCRIPPS RESEARCH INSTITUTE, THE
• 依托单位国家: 美国
• 财政年份: 2006
• 资助国家: 美国
• 起止时间: 2006-04-01 至 2018-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8697848
• 关键词: Active Sites; Address; Adopted; Adverse effects; Anti-Bacterial Agents; Anti-Infective Agents; Antineoplastic Agents; Binding; C-terminal; Catalysis; Chemicals; Chemistry; Clinical; Complex; Coupled; Development; Dihydrofolate Reductase; Enzymes; Escherichia coli; Escherichia coli Proteins; Evolution; Folate; Human; Kinetics; Lead; Mediating; Methods; Methotrexate; Molecular; Molecular Conformation; Molecular Machines; Motion; Movement; Mutation; Pathway interactions; Pharmaceutical Preparations; Play; Positioning Attribute; Property; Protein Dynamics; Proteins; Reaction; Relative (related person); Relaxation; Research; Role; Shapes; Side; Site; Staging; Structure; Temperature; Tetrahydrofolates; Therapeutic Agents; Time; Trimethoprim; X-Ray Crystallography; base; chemical reaction; cofactor; conformer; design; enzyme pathway; flexibility; inhibitor/antagonist; insight; molecular dynamics; novel; pathogen; protein structure; public health relevance; research study; scaffold; sound; theories; three dimensional structure

DESCRIPTION (provided by applicant): Proteins are dynamic molecular machines, undergoing motions on a wide range of time scales. Although there is considerable evidence both from theory and experiment that many enzymes are inherently flexible, fundamental questions about the relationship between protein dynamics and enzyme catalysis remain unanswered. Are protein motions coupled to the chemical transformation, or are they involved primarily in controlling the flux of substrate, products, or cofactors? What role do protein motion play in progression from the preorganized ground state structure to an active site configuration that facilitates the chemical reaction? What is the time scale of active site conformational changes required for catalysis? How is the energy landscape of the enzyme modulated during the catalytic cycle and how is it shaped during evolution? Are there species-related differences in protein dynamics and available conformational substates that might potentially be exploited for development of highly selective drugs that better discriminate between enzymes from humans and pathogens? These issues will be addressed using state-of-the-art NMR methods and multi-conformer room temperature X-ray crystallography to elucidate the dynamic properties of an exceptionally well- characterized enzyme, dihydrofolate reductase (DHFR). DHFR is the target for anti-folate drugs such as the anticancer agent methotrexate and the antibacterials trimethoprim and iclaprim. The proposed research will lead to new understanding of the intrinsic molecular dynamics of this important enzyme and how its motions are modulated by interaction with substrate, cofactor, and products at various stages in the catalytic cycle. It will also provide novel insights into the role of evolution in shaping the energy landscapes of E. coli and human DHFR and will advance our understanding of the relationship between protein dynamics and catalytic function.

描述（由申请人提供）：蛋白质是动态分子机器，在广泛的时间尺度上进行运动。虽然有相当多的证据，从理论和实验，许多酶是固有的灵活性，蛋白质动力学和酶催化之间的关系的基本问题仍然没有答案。蛋白质的运动是否与化学转化相关联，或者它们是否主要参与控制底物、产物或辅因子的流动？蛋白质运动在从预组织的基态结构到促进化学反应的活性位点构型的过程中扮演什么角色？催化作用所需的活性中心构象变化的时间尺度是多少？在催化循环过程中，酶的能量景观是如何调节的？在进化过程中，它又是如何形成的？蛋白质动力学和可用构象亚态中是否存在与物种相关的差异，这些差异可能用于开发更好地区分人类和病原体酶的高选择性药物？这些问题将使用最先进的NMR方法和多构象室温X射线晶体学来解决，以阐明一种非常好表征的酶二氢叶酸还原酶（DHFR）的动态特性。DHFR是抗叶酸药物如抗癌药甲氨蝶呤和抗菌药甲氧苄啶和iclaprim的靶点。拟议的研究将导致对这种重要酶的内在分子动力学的新理解，以及它的运动如何通过与底物，辅因子和催化循环中各个阶段的产物的相互作用来调节。它还将为进化在塑造E的能源景观中的作用提供新的见解。大肠杆菌和人DHFR，并将推进我们的蛋白质动力学和催化功能之间的关系的理解。