SIGMA: Small molecule Inhibitors targeting the Genetic determinants of Mutagenesis and Adaptability in Mycobacterium tuberculosis

为了在无数的化学和宿主胁迫下生存，致病细菌的等基因群体通过(i)发展具有不同代谢状态的瞬时亚群，（ii）可诱导的代谢重塑，以及（iii）应激诱导的诱变来产生表型变异。表型变异性促进了致病菌进化出抗生素耐药性的能力，因此，操纵表型变异性的下一代抗生素疗法本身将具有变革性。然而，在感染相关条件下具有临床意义的非模型致病菌中，我们对表型变异的遗传决定因素知之甚少，也不知道如何用小分子调节它们。结核分枝杆菌的表型变异导致结核病的标志性治疗挑战，结核病每年导致140万人死亡。因此，我们建议系统地表征结核分枝杆菌表型变异性的遗传决定因素以及调节它们的小分子，以便对下一代疗法进行原型设计。我们将结合新方法的发展，分枝杆菌学，功能基因组学和化学生物学的四个目标：1。阐明代谢亚群的精细结构，并鉴定这种精细结构的遗传和小分子调节剂。2. 鉴定代谢重塑在不允许生长的宿主相关应激条件下存活所必需的一整套基因。3. 鉴定侵染胁迫诱导诱变的遗传和小分子调节剂。4. 研究三种新的结核分枝杆菌根除模式，以加速其杀伤，消除其抗生素耐受亚群，并抑制耐药性的演变。

To survive myriad chemical and host stresses, isogenic populations of pathogenic bacteria generate phenotypic variability by (i) developing transient subpopulations with distinct metabolic states, (ii) inducible metabolic remodelling, and (iii) stress-induced mutagenesis. Phenotypic variability fuels the ability of pathogenic bacteria to evolve antibiotic resistance, therefore next generation antibiotic therapies which manipulate phenotypic variability itself would be transformative. However, in clinically significant non-model pathogenic bacteria under infection-relevant conditions, we know little either about genetic determinants of phenotypic variability, or about how to modulate them with small molecules. Phenotypic variability in Mycobacterium tuberculosis causes the signature treatment challenges of tuberculosis, a disease which kills 1.4 million people annually. Therefore, we propose to systematically characterise the genetic determinants of phenotypic variability in M. tuberculosis as well as small molecules which modulate them in order to prototype next generation therapies. We will combine development of new methodology, mycobacteriology, functional genomics, and chemical biology in four aims: 1. to elucidate fine structure of metabolic subpopulations and identify genetic and small-molecule modulators of this fine structure. 2. to identify the comprehensive set of genes essential for metabolic remodelling to survive host-related stress conditions that do not permit growth. 3. to identify genetic and small-molecule modulators of inducible mutagenesis under infection-relevant stress. 4. to investigate three new modes of M. tuberculosis eradication to accelerate its killing, eliminate its antibiotic-tolerant subpopulations, and suppress evolution of resistance.