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

基本信息

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
项目类别：
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

项目摘要

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浓度自动还原的机制。两种不同的肌红蛋白物种（马心和人类）中的价铁物种，按顺序排列揭示调节相应氧化蛋白的结构特征肌红蛋白氧化损伤脂蛋白的倾向是一种特殊的损害。对动脉粥样硬化分子机制的兴趣是质子。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检验这一假设，将通过确定三个不同的特征来评估机制。重点探讨自还原的动力学和热力学参数使用瞬态紫外-可见吸收光谱法对两种 Mb 物质进行反应第二个目的是通过改变温度和 pH 条件来识别质子。高价铁物质自动还原所需的来源，并确定是否存在或更多不同的质子对于调节生理机制很重要利用动力学实现低 pH（炎症部位）和中性 pH（血液环境）第三个目标是溶剂同位素效应、质子库存和定点诱变。专注于利用自由基陷阱识别蛋白质内的电子供体来源，串联质谱法和循环伏安法。