Exploring the protein structural features which regulate myoglobin's proton transfer dependent high-valent auto-reduction

探索调节肌红蛋白质子转移依赖性高价自动还原的蛋白质结构特征

• 批准号: 10436167
• 负责人: Heather Rebecca Williamson
• 金额: $ 14.2万
• 依托单位: XAVIER UNIVERSITY OF LOUISIANA
• 依托单位国家: 美国
• 财政年份: 2020
• 资助国家: 美国
• 起止时间: 2020-07-01 至 2023-12-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10436167
• 关键词: Affect; Amino Acid Sequence; Atherosclerosis; Basic Science; Biological; Biological Markers; Blood; Cardiovascular system; Cells; Data; Disease model; Electron Transport; Electrons; Environment; Enzyme Reactivation; Equipment and supply inventories; Equus caballus; Event; Exhibits; Future; Globin; Goals; Heart; Heart Diseases; Hematin; Heme; Heme Iron; Human; Inflammation; Iron; Isotopes; Kinetics; Lipoproteins; Location; Maps; Molecular; Movement; Myoglobin; Oxidants; Oxides; Pathology; Peptides; Periodicity; Physiological; Process; Proteins; Protons; Reaction; Reactive Oxygen Species; Site; Site-Directed Mutagenesis; Solvents; Source; Spectrum Analysis; Symptoms; System; Temperature; Testing; Thermodynamics; Translational Research; Water; base; cardiovascular health; catalyst; dietary; electron donor; experimental study; human disease; interest; non-Native; oxidation; oxidative damage; preference; programs; tandem mass spectrometry

The goal of this study is to understand the mechanisms of the auto-reduction of high- valent iron species in two different myoglobin species, horse heart and human, in order to uncover the structural features that regulate the corresponding oxidative protein damage. Myoglobin’s propensity to oxidatively damage lipoproteins is a particular interest in the molecular mechanism of atherosclerosis. The hypothesis is that proton and electron movements that regulate the auto-reduction can inform how we study oxidative damage in proteins and atherogenic lipoproteins. To test this assumption, the mechanism will be evaluated by determining three different features. The first aim will focus on probing the kinetic and thermodynamic parameters of the auto-reduction reaction for both Mb species using transient UV-visible absorbance spectroscopy and by varying temperature and pH conditions. The second aim is to identify the proton source necessary for auto-reduction of the high-valent iron species and determine if one or more different protons are important in regulating the mechanism at physiologically low pH (inflammation sites) and neutral pH(blood based environments) utilizing kinetic solvent isotope effects, proton inventories, and site directed mutagenesis. The third aim focuses on identifying the electron donor source within the protein utilizing radical traps, tandem mass spectrometry and cyclic voltammetry.

本研究的目的是了解高血压患者的自我还原机制， 在两种不同的肌红蛋白物种，马心和人，按顺序， 揭示调节相应氧化蛋白的结构特征 损害肌红蛋白氧化损伤脂蛋白的倾向是一种特殊的 对动脉粥样硬化的分子机制感兴趣。假设质子 调节自动还原的电子运动可以告诉我们如何学习 蛋白质和致动脉粥样硬化脂蛋白的氧化损伤。为了验证这个假设， 将通过确定三个不同的特征来评估机制。第一个目标将 重点探讨了自还原反应的动力学和热力学参数 使用瞬态UV-可见吸收光谱法对两种Mb物质进行反应， 通过改变温度和pH条件。第二个目标是识别质子 源必要的自动还原的高价铁物种，并确定是否有一个 或更多不同的质子在调节生理学上的机制中是重要的。 低pH值（炎症部位）和中性pH值（基于血液的环境）， 溶剂同位素效应、质子库存和定点诱变。第三个目标 重点在于利用自由基陷阱识别蛋白质内的电子供体源， 串联质谱和循环伏安法。

项目成果

Hidden Complexity in the Mechanism of the Autoreduction of Myoglobin Compound II.

• DOI: 10.1021/acsomega.2c02798
• 发表时间: 2022-07-05
• 期刊: ACS OMEGA
• 影响因子: 4.1
• 作者: Hill, Kamisha R.;Bailey, Breanna G.;Mouton, Meghan B.;Williamson, Heather R.
• 通讯作者: Williamson, Heather R.