Analysis of host-derived nutrient utilization pathways in M. tuberculosis

结核分枝杆菌宿主来源的养分利用途径分析

• 批准号: 8442522
• 负责人: Brian C VanderVen
• 金额: $ 23.19万
• 依托单位: CORNELL UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2013
• 资助国家: 美国
• 起止时间: 2013-02-15 至 2015-01-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8442522
• 关键词: Address; Bacteria; Biochemical; Biological Assay; Carbon; Catabolism; Cell Wall; Cessation of life; Cholesterol; Cholesterol Esters; Cholesterol Homeostasis; Chronic; Classification; Data; Defect; Disease; Energy Supply; Environment; Enzymes; Epidemic; Genes; Genetic Screening; Granuloma; Growth; Human; Immune response; Immune system; In Vitro; Infection; Inflammatory; Intervention; Lesion; Lipids; Lung; Lysosomes; Maintenance; Metabolic; Metabolic Control; Metabolic Pathway; Metabolism; Modeling; Molecular; Mutagenesis; Mycobacterium tuberculosis; Nutrient; Pathogenesis; Pathologic; Pathway interactions; Phagosomes; Phenotype; Process; Research; Source; Staging; System; Toxic effect; Tuberculosis; Work; base; cell type; design; fitness; i-cholesterol; in vitro Assay; insight; lipid metabolism; macrophage; mutant; novel; novel therapeutics; pathogen; pressure; prevent; propionyl-coenzyme A; public health relevance; screening; tuberculosis granuloma

DESCRIPTION (provided by applicant): Tuberculosis (TB) is a lasting global epidemic that claims ~1.5 million human lives annually. Mycobacterium tuberculosis (Mtb) is the causative agent of TB and this bacterium establishes an infection by surviving within macrophages and manipulating the host immune response. It is the infected macrophage that orchestrates the formation of a granuloma, the hallmark pathologic lesion associated with a TB infection. Isolated within the granuloma Mtb can persist for decades sequestered away from the pressures of the host immune response. During this persistent infection Mtb must control its metabolism to efficiently utilize host-derived nutrients for survival. It is well established that Mtb's ability o process and utilize host-derived lipid nutrients during an infection is essential for bacterial survival during an infection. Additionally, recent work has revealed that Mtb not only utilizes hos lipids as a nutrient source to supply energy producing and/or biosynthetic pathways but also actively processes toxic metabolites generated during catabolism of host lipids. By understanding the host-derived nutrient metabolic pathways in Mtb we will likely identify new weaknesses to facilitate the discovery of new therapeutic strategies against this pathogen. For this project we will characterize several mutants identified in a genetic screen designed to identify novel mutants of host nutrient utilization by Mtb. Specifically, this screen allowed for te identification of suppressor mutants that are defective in processing host-derived lipid nutrients. Aim 1: we will phenotypically classify Mtb mutants by counter screening for growth defects on different carbon sources in vitro and prioritize the mutants based on intracellular fitness in a macrophage infection model. Aim 2: will biochemically categorize the catabolic and biosynthetic metabolites from the pathways perturbed in the mutants. These studies will provide novel insight into the Mtb metabolic pathways that are essential during an infection which may be targeted by new intervention strategies.

描述（由申请人提供）：结核病（TB）是一种持久的全球流行病，每年约有150万人类的生活。结核分枝杆菌（MTB）是结核病的病因，该细菌通过在巨噬细胞中存活并操纵宿主免疫反应来建立感染。正是被感染的巨噬细胞策划了肉芽肿的形成，即与结核病感染相关的标志性病变病变。在肉芽肿MTB内分离的数十年可以持续存在，从宿主免疫反应的压力隔离。在这种持续感染期间，MTB必须控制其代谢，以有效利用宿主衍生的营养物质来生存。众所周知，在感染过程中，MTB的能力O过程并在感染过程中利用宿主衍生的脂质营养素对于感染过程中的细菌存活至关重要。此外，最近的工作表明，MTB不仅利用HOS脂质作为营养来源来供应产生能量和/或生物合成途径，而且还积极处理宿主脂质分解代谢期间产生的有毒代谢产物。通过了解MTB中宿主衍生的营养代谢途径，我们可能会发现新的弱点，以促进针对这种病原体发现新的治疗策略。对于这个项目，我们将表征在旨在鉴定MTB宿主营养利用的新型突变体的遗传筛选中鉴定出的几个突变体。具体而言，该屏幕允许识别抑制突变体，这些突变体在处理宿主衍生的脂质营养素方面有缺陷。 AIM 1：我们将通过反筛查在体外的不同碳源上的生长缺陷来表型对MTB突变体进行分类，并在巨噬细胞感染模型中基于细胞内适应性对突变体进行优先级。目标2：将从生物化学上分类突变体干扰的途径的分解代谢和生物合成代谢产物。这些研究将为MTB代谢途径提供新的见解，这些途径在感染过程中至关重要，这可能是由新的干预策略作为目标的。