Dissection of Mycobacterium tuberculosis metabolic and regulatory pathways to per

描述(由申请人提供)：该计划的目标是确定与结核分枝杆菌生长停滞(与持续感染有关的生理状态)相关的关键代谢途径/反应和调节转录因子。在持续感染的小鼠模型中，通过转录图谱对结核分枝杆菌碳代谢的初步研究导致了一种假设，即在持续状态的建立过程中发生了协调的代谢转换。它代表了生长中的和生长受阻的杆菌中截然不同的碳流模式。在生长细胞中，碳被用于产生能量和细菌生长的生物合成前体；而在持久细胞中，碳主要被动员以形成储存化合物。为了验证这一假设，13C同位素标记实验将与代谢网络模型相结合，通过测量生长和非生长稳态培养中碳异构体对其前体代谢物的分布，来确定不同途径/反应之间的碳流。这种方法将允许识别与细菌持久性有关的关键代谢途径/反应。第二，将利用报告融合和转座子突变技术来研究关键代谢基因是否以协调方式调节。这种方法将导致识别转录因子，这些转录因子在持续期间调节关键的代谢基因。这一计划有望为结核病持续感染的持续机制提供新的见解，并提供可能的策略来应对持续感染。公共卫生相关性：该计划的目标是确定结核分枝杆菌持续感染期间的关键代谢和调节事件。该计划有望带来关于结核杆菌持续机制的新知识，并提供应对持续感染的新策略。

DESCRIPTION (provided by applicant): The goal of the program is to identify the key metabolic pathways/reactions and regulatory transcription factors that are associated with M. tuberculosis growth arrest (a physiological state related to persistent infection). Preliminary study by transcription profiling of M. tuberculosis carbon metabolism in a murine model of persistent infection led to a hypothesis that a coordinated metabolic transformation occurs during the establishment of persistent state. It represents a drastic different carbon flow patterns in growing and growth-arrested bacilli. While carbons are utilized for energy generation and biosynthetic precursors for bacterial growth in growing cells; in persistent cells carbons are mainly mobilized for the formation of storage compounds. To test the hypothesis, 13C isotope-labeling experiment in combination with metabolic network modeling will be used to determine carbon flows among various pathways/reactions by measuring isotopomer distribution to their precursor metabolites in growing and nongrowing steady-state cultures. This approach will allow the identification key metabolic pathways/reactions associated with bacterial persistence. Second, reporter fusion and transposon mutagenesis technology will be utilized to study whether key metabolic genes are regulated in a coordinated mode. This approach will lead to identification of transcription factors that regulate key metabolic genes during persistence. This program is expected to provide new insights into the persistent mechanism of tubercle bacilli and offer possible strategies to tackle the persistent infection. PUBLIC HEALTH RELEVANCE: The goal of the program is to identify the key metabolic and regulatory events during the establishment of M. tuberculosis persistent infection. The program is expected to lead to new knowledge about the persistent mechanism of the tubercle bacilli and offer new strategies to tackle the persistent infection.