Mycobacterial single cell drug susceptibility

描述（由申请人提供）：某些细菌在抗生素治疗中存活的能力是治疗感染性疾病的一个严重问题。这对于人类结核病（TB）的病原体结核分枝杆菌（Mtb）尤其如此。全球结核病死亡率正在上升，尽管用于治疗这种疾病的抗生素化疗是积极和漫长的。治疗失败的原因之一是，即使在药物敏感性疾病中，也有相当数量的细菌可以在抗生素治疗中存活。我打算研究这种现象的表型耐受性，通常被称为持久性，在分枝杆菌。对表型耐受性的了解很少，也很难研究，因为它需要观察单个细胞而不是群体。在这里，我提出了一种基于荧光生物传感器和延时显微镜的新方法来检验我的假设，即细菌的生理状态在单细胞水平上预先决定抗生素的敏感性，并且这种状态可以响应于内源性和外源性刺激而波动。这些结果将使人们深入了解分枝杆菌表型耐受性的机制，从而使未来的工作重点放在更快地开发治疗结核病感染的新策略上。

DESCRIPTION (provided by applicant): The ability of some bacteria to survive antibiotic treatment is a serious problem for the treatment of infectious diseases. This is especially true fo the pathogen Mycobacterium tuberculosis (Mtb), the causative agent of human tuberculosis (TB). Global TB mortality rates are increasing, despite the aggressive and lengthy antibiotic chemotherapy used to treat the disease. One of the reasons for failed treatment is that even in drug susceptible disease a considerable population of bacteria can survive antibiotic therapy. I intend to study this phenomenon of phenotypic tolerance, often referred to as persistence, in mycobacteria. Phenotypic tolerance is poorly understood and difficult to study since it requires looking at individual cells rather than populations. Here, I propose a novel method based on fluorescent biosensors and time-lapse microscopy to test my hypothesis that bacterial physiological state predetermines antibiotic susceptibility on a single-cell level and that this stte can fluctuate in response to endogenous and exogenous stimuli. The results will give insight into the mechanisms underlying phenotypic tolerance in mycobacteria, leading to future work that will focus on developing new strategies for treating TB infections more rapidly.