Metalloprotein Mechanisms of Redox Regulation and Catalysis

氧化还原调节和催化的金属蛋白机制

基本信息

批准号：
10643866
负责人：
Stephen Wiley Ragsdale
金额：
$ 65.29万
依托单位：
UNIVERSITY OF MICHIGAN AT ANN ARBOR
依托单位国家：
美国
项目类别：
财政年份：
2021
资助国家：
美国
起止时间：
2021-09-01 至 2026-06-30
项目状态：
未结题

来源：
https://reporter.nih.gov/project-details/10643866
关键词：
Affect Anions Area Biliverdine Binding Binding Proteins Biochemical Biological Biophysics Biotechnology Carbon Dioxide Catalysis Cells Chemicals Complex Coupling Environment Enzymes Funding Gases Generations Grant Health Heme Homeostasis Human Industrialization Iron Laboratories Length Ligation Mercury Metabolic Metabolism Metalloproteins Metals Methane Methylation Microbe Molecular Chaperones Molecular Conformation Monitor Movement NADPH-Ferrihemoprotein Reductase Nuclear Receptors Oxidation-Reduction Pathway interactions Planet Earth Proteins Reaction Regulation Research Signaling Molecule Structure Sulfur Tail Toxic effect Wood material Work career catalyst circadian pacemaker cofactor heme oxygenase-2 methyl radical microbial novel protein degradation protein protein interaction sample fixation sensor success trafficking

Affect Anions Area Biliverdine Binding Binding Proteins Biochemical Biological Biophysics Biotechnology Carbon Dioxide Catalysis Cells Chemicals Complex Coupling Environment Enzymes Funding Gases Generations Grant Health Heme Homeostasis Human Industrialization Iron Laboratories Length Ligation Mercury Metabolic Metabolism Metalloproteins Metals Methane Methylation Microbe Molecular Chaperones Molecular Conformation Monitor Movement NADPH-Ferrihemoprotein Reductase Nuclear Receptors Oxidation-Reduction Pathway interactions Planet Earth Proteins Reaction Regulation Research Signaling Molecule Structure Sulfur Tail Toxic effect Wood material Work career catalyst circadian pacemaker cofactor heme oxygenase-2 methyl radical microbial novel protein degradation protein protein interaction sample fixation sensor success trafficking

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项目摘要

Abstract for Metalloprotein Mechanisms of Redox Regulation and Catalysis This proposal covers the three R01 grants funding my laboratory and aims to fill gaps in understanding the mechanisms of crucial aspects of redox regulation and catalysis by metalloproteins from microbes to humans. Successful completion of this work will reveal novel mechanisms with broad significance to human health, the environment, and biotechnology. Our research integrates a wide variety of biological, biophysical, biochemical and computational approaches. In Project Area 1, we will extend recent discoveries of novel bioinorganic and enzymatic mechanisms of anaerobic microbial CO and CO2 fixation in the Wood-Ljungdahl pathway (WLP), proposed to have fueled the origin of live on earth. We will reveal the mechanisms of these ancient enzymes: their generation and use of CO as a substrate, formation of bioorganometallic catalytic intermediates, utilization of nucleophilic and paramagnetic metal centers as catalysts, requirement of large domain movements and an interprotein CO channel and recently identified alcove for CO binding and CO2 fixation. We will define how these unique features choreograph redox activation, substrate and partner protein binding, leading to biological transformation that chemists are trying to mimic to more rapidly and efficiently accomplish chemically challenging reactions, e.g., to sequester, activate and convert CO2, methane and syngas into industrially important chemical feedstocks and fuels. While I started my career studying the WLP, I have applied the same expertise to other important evolving problems of metabolic regulation in humans by CO and metals and of mercury toxicity. In Project Area 2, we propose to deliver important discoveries on how human metabolism, metal homeostasis and the circadian clock are regulated by heme regulatory motifs (HRMs), signaling molecules (CO and NO), and cellular heme levels and redox poise. Focusing on heme oxygenase-2 (HO2), we will explore crucial conformational changes between the core and tail of HO2 and how these movements control protein turnover, protein-protein interactions, and heme conversion to CO, biliverdin and Fe. We will explore the hypothesis that HO2 serves a dual function in the cell in controlling heme trafficking and turnover. We will monitor the dynamics and interactions of full length HO2 with its redox partner cytochrome P450 reductase and with its heme donor GAPDH and define mechanisms that regulate heme-controlled HO2 turnover. Following up on our finding that the nuclear receptor Rev-Erbb uses a novel mechanism of redox- chemical coupling to serve as a CO/NO sensor, we will address how redox and gas binding affect its structure, function, activity and its interactions with partners like NCoR1 and its heme chaperone. In Project Area 3, recent successes in purifying and crystallizing the active HgcAB complex and defining its unusual thiolate- coordinated B12 cofactor, enable our proposed studies of the mechanism of microbial mercury methylation. We will determine the HgcAB structure, the redox and ligation states of the metal centers during catalysis, and whether a methyl radical or anion is used by these B12 and iron-sulfur clusters during catalysis.

氧化还原调节和催化的金属蛋白机制的摘要该提案涵盖了三个R01授予我的实验室资助的资金，并旨在填补理解的空白金属蛋白从微生物到人的氧化还原调节和催化的关键方面的机制。成功完成这项工作将揭示对人类健康具有广泛意义的新型机制，环境和生物技术。我们的研究整合了各种生物学，生物物理，生化和计算方法。在项目区域1中，我们将扩展最新的新型生物无机发现和木质微生物CO和二氧化碳固定在木材ljungdahl途径（WLP）中的酶促机制，提议助长了地球上的生命的起源。我们将揭示这些古老酶的机制：它们的产生和使用CO作为底物，形成生物有线金属催化中间体，利用率作为催化剂的亲核和顺磁性金属中心，大型域运动的需求和解释蛋白CO通道，并最近确定了用于CO BINDING和CO2固定的壁co。我们将定义如何这些独特的特征编舞氧化还原激活，底物和伴侣蛋白质结合，导致生物学化学家正试图更快速有效地实现化学成就的转变具有挑战性的反应，例如，隔离，激活和转化二氧化碳，甲烷和同符于工业重要的化学原料和燃料。当我开始研究WLP的职业生涯时，我已经应用了同样的 CO和金属和金属和金属中其他重要不断发展的代谢调节问题的专业知识汞毒性。在项目区域2中，我们建议提供有关人类新陈代谢的重要发现金属稳态和昼夜节律时钟由血红素调节图案（HRMS）调节，信号传导分子（CO和NO），细胞血红素水平和氧化还原固定。专注于血红素氧酶-2（HO2），我们将探索HO2核心和尾部之间的关键构象变化以及这些运动如何控制蛋白质更新，蛋白质 - 蛋白质相互作用以及血红素转化为CO，Biliverdin和Fe。我们将探讨HO2在控制血红素贩运和周转方面具有双重功能的假设。我们将监视全长HO2与其氧化还原伙伴细胞色素P450的动力和相互作用还原酶及其血红素供体GAPDH并定义调节血红素控制HO2的机制周转。跟进我们的发现，核受体Rev-erbb使用了一种新型的氧化还原机制化学耦合以用作CO/NO传感器，我们将解决氧化还原和气体结合如何影响其结构，功能，活动及其与NCOR1及其血红素伴侣等合作伙伴的相互作用。在项目区域3，最近在纯化和结晶活性的HGCAB复合物中取得了成功，并定义了其异常的硫醇酯 - 协调的B12辅因子，使我们对微生物汞甲基化机理的提议研究。我们将确定催化过程中金属中心的HGCAB结构，氧化还原和连接状态以及这些B12和铁硫簇在催化过程中使用的是甲基自由基还是阴离子。