Structure and Dynamics of Cyclooxygenase Catalysis and Inhibition

环加氧酶催化和抑制的结构和动力学

基本信息

批准号：
9315899
负责人：
MICHAEL G MALKOWSKI
金额：
$ 37.28万
依托单位：
HAUPTMAN-WOODWARD MEDICAL RESEARCH INST
依托单位国家：
美国
项目类别：
财政年份：
2015
资助国家：
美国
起止时间：
2015-08-01 至 2018-07-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/9315899
关键词：
Active Sites Acute Affect Amphipathic Alpha Helix Anabolism Arachidonic Acids Aspirin Binding Biochemical Cardiovascular Diseases Cardiovascular system Catalysis Catalytic Domain Cessation of life Chronic Communication Complex Consumption Coupled Coxibs Crystallization Cysteine Detergents Development Diet Disease Drug Utilization Electron Spin Resonance Spectroscopy Enzymes Event Fatty Acids Goals Health Professional Inflammation Investigation Isoenzymes Ligand Binding Ligands Lipid Bilayers Malignant Neoplasms Maps Masks Mediating Membrane Methods Modeling Molecular Molecular Conformation Motion Movement Nature Non-Steroidal Anti-Inflammatory Agents Pathology Patients Pharmaceutical Preparations Play Property Prostaglandin-Endoperoxide Synthase Prostaglandins Protein Conformation Proteins Regulation Reporter Risk Roentgen Rays Role Signal Transduction Site Source Spin Labels Structure Technology Testing Time base biophysical analysis cyclooxygenase 1 cyclooxygenase 2 inhibitor/antagonist innovation insight monomer mutant nanodisk novel strategies novel therapeutics public health relevance reconstitution risk minimization tyrosine radical

Active Sites Acute Affect Amphipathic Alpha Helix Anabolism Arachidonic Acids Aspirin Binding Biochemical Cardiovascular Diseases Cardiovascular system Catalysis Catalytic Domain Cessation of life Chronic Communication Complex Consumption Coupled Coxibs Crystallization Cysteine Detergents Development Diet Disease Drug Utilization Electron Spin Resonance Spectroscopy Enzymes Event Fatty Acids Goals Health Professional Inflammation Investigation Isoenzymes Ligand Binding Ligands Lipid Bilayers Malignant Neoplasms Maps Masks Mediating Membrane Methods Modeling Molecular Molecular Conformation Motion Movement Nature Non-Steroidal Anti-Inflammatory Agents Pathology Patients Pharmaceutical Preparations Play Property Prostaglandin-Endoperoxide Synthase Prostaglandins Protein Conformation Proteins Regulation Reporter Risk Roentgen Rays Role Signal Transduction Site Source Spin Labels Structure Technology Testing Time base biophysical analysis cyclooxygenase 1 cyclooxygenase 2 inhibitor/antagonist innovation insight monomer mutant nanodisk novel strategies novel therapeutics public health relevance reconstitution risk minimization tyrosine radical

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项目摘要

DESCRIPTION (provided by applicant): Cyclooxygenases (COX-1 and COX-2) oxygenate arachidonic acid to generate prostaglandins and are inhibited by aspirin, nonselective nonsteroidal anti-inflammatory drugs (NSAIDs), and COX-2 selective diarylheterocyclic based drugs (coxibs). COX-1 and COX-2 are membrane-associated homodimers that bind to one leaflet of the lipid bilayer via a membrane-binding domain comprised of amphipathic helices. As a consequence, the enzymes have traditionally required the presence of detergents to maintain the protein in a stable and active form during functional and structural characterization. A new paradigm has emerged with respect to COX catalysis and regulation. In this model, COX functions as a conformational heterodimer with one monomer active at a given time. Common dietary FAs and nonselective NSAIDs bind to one monomer of the homodimer to modulate the oxygenation of substrates in the other monomer through an allosteric/catalytic couple. The molecular mechanism governing crosstalk between monomers is not known and static pictures derived from crystal structures of COX do not provide any insight into the conformational motions responsible for this dynamical interplay. We surmise that detergent binding and the restricted confines of the crystal lattice have masked these conformational motions. Hence, a new approach to study COX catalysis in solution and in the absence of detergent is needed. We propose to couple the use of nanodisc-reconstituted COX-2 with site- directed spin-labeling ESR spectroscopic technologies to characterize the protein conformational dynamics associated with COX catalysis and inhibition. The objectives are to identify the conformational motions responsible for: a) ligand access to the cyclooxygenase channel and b) communication between monomers. Understanding the molecular basis of how the binding of different ligands induces conformational motions responsible for crosstalk between monomers bridges the gap between the static information derived from COX crystal structure analysis and the dynamical character of COX as it relates to the modulation of COX function.

描述（由适用提供）：环氧酶（COX-1和COX-2）氧化蛛网膜酸以产生前列腺素，并被阿司匹林，非效应的非甾体类抗炎药（NSAIDS）和COX-2选择性二二叶二脂蛋白coxclicclic药物（Coxibs）抑制。 COX-1和COX-2是与膜相关的同型二聚体，通过完成两亲螺旋的膜结合结构域结合脂质双层的一个小叶。结果，传统上，这些酶要求确定剂在功能和结构表征期间以稳定而活跃的形式保持蛋白质。关于Cox催化剂和调节，已经出现了新的范式。在此模型中，COX充当一个在给定时间活跃的单体的构象异二聚体。常见的饮食FA和非选择性NSAID与同二聚体的一个月结合，通过一对变构/催化夫妇调节另一种单体中底物的氧合。控制单体之间的串扰的分子机制尚不清楚，源自Cox的晶体结构的静态图片并未提供对负责这种动态相互作用的构象运动的任何见解。我们冲浪确定结合和晶格的受限范围已掩盖了这些构象运动。因此，需要一种研究溶液中的Cox催化的新方法，并且需要在没有确定的情况下。我们建议将使用纳米盘重新确定的COX-2与位置定向的自旋标记的ESR光谱技术来表征与Cox催化剂和抑制相关的蛋白质构象动力学。这些目标是确定负责的构象运动：a）配体访问环氧酶通道和b）单体之间的通信。了解不同配体结合的分子基础如何影响构象运动，负责构象运动，使单体之间的串扰桥梁桥接了Cox Crystal结构分析的静态信息与COX的动态特征之间的差距，因为它与Cox功能的调节有关。