Bioinorganic Explorations of Host-defense Proteins

宿主防御蛋白的生物无机探索

基本信息

批准号：
10530840
负责人：
ELIZABETH M NOLAN
金额：
$ 31.44万
依托单位：
MASSACHUSETTS INSTITUTE OF TECHNOLOGY
依托单位国家：
美国
项目类别：
财政年份：
2017
资助国家：
美国
起止时间：
2017-08-15 至 2026-07-31
项目状态：
未结题

来源：
https://reporter.nih.gov/project-details/10530840
关键词：
Address Anti-Bacterial Agents Area Bacterial Physiology Binding Biochemical Biological Biophysics Case Study Chemistry Clinical Research Complex Crystallization Development Diagnostic Disease Disulfides Environment Epithelial Cells Extracellular Space Funding Goals Growth Homeostasis Host Defense Human Human Pathology Immune Infection Infection prevention Inflammation Inflammatory Innate Immune Response Innate Immune System Invaded Investigation Ions Laboratories Leukocyte L1 Antigen Complex Lighting Link Metals Methionine Modeling Molecular Mus Nutrient Nutritional Immunity Organism Outcome Pathology Peptide Hydrolases Physiology Play Post-Translational Protein Processing Property Proteins Research Resistance Role Rosaniline Dyes S100A8 gene S100A9 gene Site Structure Testing Therapeutic Transition Elements Urinary tract infection Uropathogenic E. coli Work biophysical properties design disulfide bond expectation extracellular host-microbe interactions human disease in vivo insight microbial molecular modeling neutrophil novel diagnostics oxidation pathogen pathogenic Escherichia coli pathogenic bacteria pathogenic fungus pathogenic microbe prevent response uptake

项目摘要

PROJECT SUMMARY The overarching goal of this renewal application is to elucidate the molecular basis for how human calprotectin (CP, S100A8/S100A9 oligomer) functions in the metal-withholding innate immune response, and to evaluate its impact on the physiology of uropathogenic Escherichia coli (UPEC), which cause the majority of urinary tract infections in humans. Transition metals are essential nutrients for all organisms, and the availability of these nutrients plays a critical role during microbial infection. Consequently, the human innate immune system launches a metal-withholding response and deploys metal-sequestering host-defense proteins into the extracellular space to limit metal availability and hinder pathogen growth. CP is an abundant and functionally versatile metal-withholding protein; it sequesters multiple metal nutrients including Mn(II), Fe(II), Ni(II) and Zn(II). Recent studies by our laboratory and others provide compelling evidence that the molecular speciation of extracellular CP is a heterogenous ensemble of different species that arises from different metal-bound forms as well as oxidative post-translational modifications. We hypothesize that this complex molecular speciation of CP, including the occurrence of methionine oxidation and disulfide bonding, has profound consequences for its extracellular function and lifetime. Recent studies by our laboratory and others also demonstrate that CP is a Cu-withholding protein. We hypothesize that CP sequesters both Cu(II) and Cu(I) and that this function impacts the physiology and metal homeostasis in diverse bacterial pathogens including UPEC. In Aim 1, we will examine disulfide bond formation within and between CP heterodimers, the biophysical properties of these disulfide-linked species, and their ability to sequester metals from bacterial pathogens. In Aim 2, we will evaluate the Cu(II/I)-binding properties of CP and the consequences of multi- metal sequestration by CP on UPEC as a case study. We expect that these investigations will advance the molecular model for how CP contributes to the metal-sequestering innate immune response, underscore the importance of considering CP species that result from oxidative posttranslational modification, and elucidate the molecular basis for Cu withholding by CP. Moreover, we expect that our studies of the interplay of CP and UPEC will provide new insight into how the host and pathogen compete for Cu and other nutrient metals. We further expect that the outcomes of this initiative may guide the design and development of novel diagnostic, preventative and therapeutic approaches for microbial infections and other pathologies such as inflammatory diseases that involve CP.

项目摘要这种更新应用的总体目标是阐明人类钙卫蛋白的分子基础（CP，S100A8/S100A9低聚物）在金属与先天免疫反应中起作用，并评估其对大部分尿路的尿素疾病大肠杆菌（UPEC）的影响人类感染。过渡金属是所有生物的必不可少的营养素，并且这些物质的可用性营养在微生物感染中起着至关重要的作用。因此，人类先天免疫系统发射金属持有响应，并将金属序列的宿主防御蛋白部署到细胞外空间以限制金属可用性并阻碍病原体生长。 CP是一种丰富的功能多功能金属持有蛋白；它隔离了多种金属营养素，包括Mn（II），Fe（II），Ni（ii）和 Zn（ii）。我们的实验室和其他研究提供了令人信服的证据表明分子形成细胞外CP是来自不同金属结合的不同物种的异质集合形式以及氧化后翻译修饰。我们假设这种复合物分子 CP的形态，包括蛋氨酸氧化和二硫键的发生，具有深刻的其细胞外功能和寿命的后果。我们的实验室和其他人的最新研究也证明CP是一种持有的蛋白质。我们假设CP隔离Cu（II）和Cu（I）和此功能会影响各种细菌病原体的生理和金属稳态 UPEC。在AIM 1中，我们将检查CP异二聚体内外的二硫键形成，这些二硫键物种的生物物理特性及其从细菌中隔离金属的能力病原体。在AIM 2中，我们将评估CP的CU（II/I）结合特性以及多数的后果 CP在UPEC上作为案例研究。我们希望这些调查将推进 CP如何促进金属序列的先天免疫反应的分子模型，强调考虑由氧化后翻译后修饰引起的CP物种的重要性，并阐明 CP预扣CU的分子基础。此外，我们期望我们对CP和CP相互作用的研究 UPEC将提供有关宿主和病原体如何竞争CU和其他营养金属的新见解。我们进一步期望该计划的结果可能指导新型诊断的设计和开发，微生物感染和其他病理（例如炎症）的预防和治疗方法涉及CP的疾病。