Metabolic determinants of barrier function in rifampin-sensitive and -resistant Mtb

项目2-利福平敏感和耐药结核分枝杆菌屏障功能的代谢决定因素 项目负责人：李京姬 联合调查员：瓦莱丽·米兹拉希 合作调查人员：杰里米·洛克(核心D)，D·布兰奇·穆迪(核心B) 摘要 这个项目的首要目标是阐明特定的细胞膜结构-活性关系。 中介屏障功能。更安全、更简单的结核病药物和治疗的一个关键和相当字面上的障碍是它的 非常不寻常的细胞包膜。因此，对MTB包络的势垒函数的改进知识代表了 开发更好、更安全的药物的潜在蓝图。与大多数细菌不同，结核分枝杆菌(Mtb) 包膜由一种独特的多层结构组成，其物理化学性质被广泛认为 介导了抗生素耐药性的内在机制。使用新开发的全生物体化学品 谱分析和基因组规模CRISPRi技术，我们挑战了长期认为结核分枝杆菌细胞壁是一种 静态的和不必要的化学屏障。初步研究表明结核分枝杆菌的囊膜是化学的。 具有选择性，其阻隔活性并不是其大块物理化学性质的简单产物。这些数据 进一步表明，其组成和屏障功能都是动态调节的。这个项目特别是 专注于通过一线结核病药物利福平的治疗透镜实现结核分枝杆菌屏障功能。我们专注于 利福平因其对药物敏感结核病独特的治疗缩短和灭菌活性，以及其 在耐药结核病生物学中的定义作用。此外，因为利福平有一个单一的，众所周知的 作用靶点是位于细胞质中的rna聚合酶b亚单位，它是一个潜在的模型。 这可以阐明适用于任何以胞浆为靶点的药物的一般原则。

Project 2 - Metabolic determinants of barrier function in rifampin-sensitive and -resistant Mtb Project Leader: Kyu Rhee Co-investigator: Valerie Mizrahi Collaborating investigators: Jeremy Rock (Core D), D. Branch Moody (Core B) ABSTRACT The overarching goal of this project is to elucidate specific cell envelope structure-activity relationships mediating barrier function. A key and quite literal barrier to safer and simpler drugs and treatments for TB is its highly unusual cell envelope. Improved knowledge of the barrier function of the Mtb envelope thus represents a potential blueprint to developing better safer drugs. Unlike most bacteria, the Mycobacterium tuberculosis (Mtb) envelope consists in a unique multilayered structure whose physico-chemical properties are widely believed to mediate an intrinsic mechanism of antibiotic resistance. Using newly developed whole organism chemical profiling and genome scale CRISPRi technologies, we challenge the longstanding view of Mtb cell wall as a static and impermeant chemical barrier. Preliminary studies indicate that the Mtb cell envelope is chemically selective, and its barrier activity is not a simple product of its bulk physico-chemical properties. These data further show that both its composition and barrier function are dynamically regulated. This project specifically focuses on Mtb barrier function through the therapeutic lens of the frontline TB drug rifampicin. We focus on rifampicin because of its unique treatment shortening and sterilizing activities against drug-sensitive TB, and its defining role in the biology of drug-resistant TB. In addition, because rifampicin has a single, well understood target of action, the b subunit of RNA polymerase, which is located in the cytosol, it serves as a potential model that could elucidate general principles that apply to any drug with cytosolic targets.