The role of nanocompartments in M. tuberculosis pathogenesis

纳米区室在结核分枝杆菌发病机制中的作用

• 批准号: 10689049
• 负责人: Sarah A Stanley
• 金额: $ 37.93万
• 依托单位: UNIVERSITY OF CALIFORNIA BERKELEY
• 依托单位国家: 美国
• 财政年份: 2019
• 资助国家: 美国
• 起止时间: 2019-09-18 至 2024-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10689049
• 关键词: Aldehydes; Altruism; Antibiotic Therapy; Archaea; Attenuated; Bacteria; Biochemistry; Cells; Characteristics; Data; Defense Mechanisms; Drug Metabolic Detoxication; Dyes; Encapsulated; Environment; Enzymes; Eukaryota; Genes; Grant; Growth; Homologous Gene; Hydrogen Peroxide; Immunologics; In Vitro; Individual; Infection; Inflammation; Link; Lipid Peroxides; Lipids; Lysosomes; M. tuberculosis genome; Macrophage; Molecular; Mycobacterium tuberculosis; NADP; NADPH Oxidase; Organelles; Oxidases; Oxidative Stress; Oxidative Stress Induction; Pathogenesis; Peroxidases; Peroxides; Persons; Phagocytes; Predisposition; Production; Proteins; Reactive Oxygen Species; Resistance; Respiratory Burst; Role; System; Testing; Virulence; attenuation; axenic culture; bacterial genetics; enzyme activity; experimental study; extracellular; human pathogen; in vivo; insight; microbicide; mouse model; mutant; novel; pathogen; pathogenic bacteria; resistance mechanism; stability testing; stressor; success

Contact PD/PI: Stanley, Sarah A Project Summary. The bacterial pathogen Mycobacterium tuberculosis is highly resistant to oxidative stress encountered in the host, however defense mechanisms remain poorly characterized. This proposal seeks to characterize a nanocompartment system in M. tuberculosis that we propose contributes to defense against oxidative stress. Nanocompartments are protein-based organelles that encapsulate an enzymatic cargo, often an enzyme related to oxidative defense. Although genes encoding nanocompartments are widespread in bacteria and archaea, their endogenous functions are not well understood and it is not clear what benefit the encapsulation of specific enzymes provides. We have discovered that M. tuberculosis has a bacterial nanocompartment system that is required for defense against oxidative stress. This system consists of the encapsulin protein Cfp29 and the cargo protein DypB, a dye decolorizing peroxidase. Our hypothesis is that the M. tuberculosis DypB nanocompartment system is required for resisting oxidative stresses encountered in host macrophages. Building on preliminary data in which we show that DypB encapsulin mutants are attenuated for growth in macrophages, and that these mutants are also susceptible to H2O2 at pH 4.5 in axenic culture we test this hypothesis in three aims. 1) Determine whether encapsulation promotes DypB stability and function; 2) Determine whether the M. tuberculosis DypB encapsulin system is required for defense against lipid peroxides; 3) Determine the role of the DypB nanocompartment in virulence of M. tuberculosis. If successful, the proposed experiments will provide the first link between a nanocompartment system and bacterial virulence, advancing our understanding of how M. tuberculosis, and possibly other pathogens, defend against diverse oxidative stresses encountered in the host. In addition, these studies will provide insights into the function of encapsulin systems and the specific role of the shell protein. Finally, these studies will advance our understanding of the endogenous functions of DyP peroxidases, which are widespread throughout bacteria, archaea, and eukaryotes Page 6 Project Summary/Abstract

联系 PD/PI：Stanley, Sarah A 项目摘要。细菌病原体结核分枝杆菌对氧化应激具有高度抵抗力 然而，防御机制的特征仍然不明确。该提案旨在 描述了结核分枝杆菌中的纳米区室系统，我们认为该系统有助于防御 氧化应激。纳米室是基于蛋白质的细胞器，通常封装酶促物质 一种与氧化防御相关的酶。尽管编码纳米区室的基因广泛存在于 细菌和古细菌，它们的内源功能尚不清楚，也不清楚对细菌和古细菌有什么好处 提供特定酶的封装。我们发现结核分枝杆菌有一种细菌 防御氧化应激所需的纳米室系统。该系统包括 封装蛋白 Cfp29 和货物蛋白 DypB（一种染料脱色过氧化物酶）。我们的假设是 结核分枝杆菌 DypB 纳米室系统是抵抗在结核杆菌中遇到的氧化应激所必需的 宿主巨噬细胞。基于初步数据，我们表明 DypB 封装蛋白突变体 在巨噬细胞中生长减弱，并且这些突变体在无菌条件下也对 pH 4.5 的 H2O2 敏感 我们从三个目标来检验这一假设。 1) 确定封装是否促进 DypB 稳定性和 功能; 2) 确定是否需要结核分枝杆菌 DypB 封装蛋白系统来防御 脂质过氧化物； 3)确定DypB纳米室在结核分枝杆菌毒力中的作用。如果 如果成功的话，所提出的实验将提供纳米室系统和纳米室系统之间的第一个联系 细菌毒力，增进我们对结核分枝杆菌以及可能的其他病原体如何防御的了解 对抗宿主遇到的多种氧化应激。此外，这些研究将提供以下见解： 封装蛋白系统的功能和壳蛋白的具体作用。最后，这些研究将取得进展 我们对 DyP 过氧化物酶内源性功能的理解，这些功能广泛存在于 细菌、古细菌和真核生物 第6页 项目概要/摘要