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

基本信息

批准号：
10020315
负责人：
Sarah A Stanley
金额：
$ 38.11万
依托单位：
UNIVERSITY OF CALIFORNIA BERKELEY
依托单位国家：
美国
项目类别：
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/10020315
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 Hydrogen Peroxide Immunologics In Vitro Individual Infection Inflammation Link Lipid Peroxides Lipids Lysosomes M. tuberculosis genome Molecular Mycobacterium tuberculosis NADP NADPH Oxidase Organelles Oxidases Oxidative Stress Pathogenesis Peroxidases Peroxides Phagocytes Production Proteins Reactive Oxygen Species Resistance Respiratory Burst Role System Testing Virulence attenuation axenic culture bacterial genetics base enzyme activity experimental study extracellular human pathogen in vivo insight macrophage microbicide mouse model mutant novel pathogen pathogenic bacteria resistance mechanism stability testing stressor success

项目摘要

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抗性在宿主中遇到的，但是防御机制的特征仍然很差。该提议试图表征结核分枝杆菌中的纳米室系统，我们提出的有助于防御氧化应激。纳米室是基于蛋白质的细胞器，封装酶促货物，通常与氧化防御有关的酶。尽管编码纳米室的基因在细菌和古细菌，它们的内源性功能尚不清楚，尚不清楚有什么好处特定酶的封装提供。我们发现结核分枝杆菌具有细菌防御氧化应激所必需的纳米室系统。该系统由封装蛋白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纳米室系统需要抵抗遇到的氧化应激寄主巨噬细胞。在初步数据的基础上，我们表明DYPB封装突变体是减弱巨噬细胞的生长，并且这些突变体在pH 4.5中也容易受到H2O2的影响文化我们以三个目标检验了这一假设。 1）确定封装是否促进了DYPB稳定性和功能; 2）确定防御是否需要用于防御的结核分枝杆菌DYPB封装系统脂质过氧化物； 3）确定DYPB纳米室在结核分枝杆菌毒力中的作用。如果成功的实验将提供纳米室系统和细菌毒力，促进我们对结核分枝杆菌和可能其他病原体的理解反对宿主遇到的各种氧化应激。此外，这些研究将提供有关封装系统的功能和壳蛋白的特定作用。最后，这些研究将进步我们对DYP过氧化物酶的内源性功能的理解，这些功能广泛细菌，古细菌和真核生物第6页项目摘要/摘要