Exploration of quorum sensing in tuberculosis

结核病群体感应的探索

• 批准号: 10628011
• 负责人: Jeffrey D. Cirillo
• 金额: $ 19.28万
• 依托单位: TEXAS A&M UNIVERSITY HEALTH SCIENCE CTR
• 依托单位国家: 美国
• 财政年份: 2022
• 资助国家: 美国
• 起止时间: 2022-05-01 至 2025-04-30
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10628011
• 关键词: Actinomycetales; Affect; Animals; Antibiotics; Bacteria; Binding; Cells; Characteristics; Communicable Diseases; Critical Pathways; Data; Disease; Environment; Epithelial Cells; Exposure to; Gene Expression; Gene Expression Regulation; Genes; Genome; Genus Mycobacterium; Goals; Growth; Homologous Gene; Human; Infection; Intervention; Length; Leprosy; Light; Link; Macrophage; Metabolism; Microbial Biofilms; Molecular; Muramidase; Mycobacterium avium; Mycobacterium fortuitum; Mycobacterium intracellulare; Mycobacterium kansasii; Mycobacterium leprae; Mycobacterium marinum; Mycobacterium tuberculosis; Mycobacterium ulcerans; Organic Chemistry; Pathogenesis; Pathway interactions; Phenotype; Pigments; Play; Population; Process; Production; Proteins; Regulation; Regulatory Pathway; Resuscitation; Role; Side; Signal Transduction; Signaling Molecule; Skin; Streptomyces; Streptomyces coelicolor; Streptomyces griseus; Structure; System; Toxin; Tuberculosis; Virulence; butyrolactone; density; experience; extracellular; genetic regulatory protein; human disease; insight; latent infection; lung pathogen; member; multidisciplinary; mycobacterial; novel; pathogen; prevent; quorum sensing; reactivation from latency; response; sensor; therapy development

PROJECT SUMMARY Mycobacterium are responsible for many important human diseases, including tuberculosis and leprosy. Bacterial species use inter-bacterial signaling or quorum sensing (QS) to coordinate gene regulation in response to their environment. Despite this fact and the presence of numerous QS molecule responsive regulators (LuxR homologues) in all mycobacterial genomes sequenced, no quorum sensing molecules have been identified in any mycobacterial species. The only potential signaling molecule yet identified is resuscitation promoting factor (Rpf) that is a lysozyme-like protein that can stimulate reactivation of latent tuberculosis. As an exploratory project, we set out in search of the best way to identify QS molecules from mycobacteria. Most likely due to the extremely low concentrations of QS molecules required to signal, nearly all QS molecules have been identified through use of a sensor strain that produces light or pigment upon exposure to QS molecules. Since most bacterial sensor strains are Gram negatives, making it unsurprising that they have not been used successfully to identify mycobacterial QS molecules, we searched for a new sensor system. We reasoned that a sensor based on Streptomyces, an Actinomycetales closely related to Mycobacterium, would be likely to respond to mycobacterial QS molecules. In our preliminary studies, we found that Streptomyces griseus and S. coelicolor can respond to mycobacterial QS molecules. The use of a novel QS sensor strain allowed us to purify two of these molecules, designated MAI-1 and MAI-2, determine partial structure for MAI-1 and demonstrate impacts of MAI-1 and MAI-2 on virulence-related phenotypes. In this application we propose to further analyze the QS pathways in mycobacteria to determine their role in pathogenesis. This will be accomplished through two specific aims: 1) Identification of mycobacterial QS molecules. Our working hypothesis is that mycobacterial QS molecules are structurally related to γ- butyrolactone (GBL) QS molecules in Streptomyces. Our preliminary studies demonstrate that MAI-1 and MAI-2 can trigger QS pathways in S. coelicolor, suggesting that they are related to each other and to GBLs, but we have not yet fully determined their structures. In this aim, we will utilize our novel sensor to determine their structures and confirm their ability to function as signaling molecules. 2) Dissect the mechanisms of QS signaling in mycobacteria. Our working hypothesis is that MAI-1 and MAI-2 are made by mycobacteria to control gene expression in density-dependent fashion. Our preliminary studies developed a screen for production of MAI molecules by mycobacteria and found that MAI molecules enhance biofilm formation, colonization of epithelial cells and macrophages and growth in macrophages. We will analyze the pathways involved in synthesis of these QS molecules in mycobacteria. The overall goal of these studies is to understand how these QS molecules are made and affect the ability of mycobacteria to cause disease.

项目摘要 分枝杆菌负责许多重要的人类疾病，包括结核病和麻风病。 细菌种类使用细菌间信号传导或法规传感（QS）来协调基因调节 对他们的环境的反应。尽管这一事实以及存在众多QS分子响应 在所有分枝杆菌基因组中，调节剂（LuxR同源物）测序，没有群体感应分子具有 在任何分枝杆菌中都被鉴定出来。尚未确定的唯一潜在信号分子是 复苏促进因子（RPF）是一种溶菌酶样蛋白，可以刺激潜在的重新激活 结核。作为一个探索性项目，我们着手寻找从中识别QS分子的最佳方法 分枝杆菌。最有可能是由于信号所需的QS分子极低的原因，几乎 所有QS分子都通过使用传感器应变来鉴定 暴露于QS分子。由于大多数细菌传感器菌株都是革兰氏剂，因此它并不令人惊讶 他们尚未成功使用它们来识别分枝杆菌QS分子，我们搜索了一个新的 传感器系统。我们认为基于链霉菌的传感器，一个与 分枝杆菌可能会对分枝杆菌QS分子反应。在我们的初步研究中，我们 发现晶状体细菌和卵链球链球菌可以对分枝杆菌QS分子反应。使用 一种新颖的QS传感器应变使我们能够净化其中两个指定为MAI-1和MAI-2的分子确定 MAI-1的部分结构并证明MAI-1和MAI-2对病毒相关表型的影响。在 我们建议的这一应用程序进一步分析了分枝杆菌中的QS途径，以确定它们在 发病。这将通过两个具体的目的来完成：1）识别分枝杆菌QS 分子。我们的工作假设是分枝杆菌QS分子在结构上与γ-相关 链霉菌中的丁蜜酮（GBL）QS分子。我们的初步研究表明MAI-1和 MAI-2可以触发S. coelicolor中的QS途径，这表明它们彼此相关并与GBL相关， 但是我们尚未完全确定它们的结构。在此目标中，我们将利用我们的新传感器来确定 它们的结构并确认它们充当信号分子的能力。 2）剖析机制 分枝杆菌中的QS信号传导。我们的工作假设是MAI-1和MAI-2是由分枝杆菌制成的 以密度依赖性方式控制基因表达。我们的初步研究开发了一个屏幕 分枝杆菌生产MAI分子，发现MAI分子增强了生物膜的形成， 上皮细胞和巨噬细胞的定殖以及巨噬细胞的生长。我们将分析路径 参与分枝杆菌中这些QS分子的合成。这些研究的总体目标是 了解这些QS分子是如何制成的，并影响分枝杆菌引起疾病的能力。