Membrane Interaction of Mycobacterium tuberculosis Virulence Factors

结核分枝杆菌毒力因子的膜相互作用

• 批准号: 9279717
• 负责人: Jianjun Sun
• 金额: $ 33.98万
• 依托单位: UNIVERSITY OF TEXAS EL PASO
• 依托单位国家: 美国
• 财政年份: 2011
• 资助国家: 美国
• 起止时间: 2011-04-08 至 2021-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9279717
• 关键词: Acetylation; Alveolar Macrophages; Animals; Antigens; Applications Grants; Attenuated; Binding; Biochemical; Cells; Cessation of life; Circular Dichroism; Collaborations; Complex; Cytosol; Development; Disease; Dissociation; Drug Design; Escherichia coli; Event; Filtration; Fluorescence Microscopy; Fluorescence Spectroscopy; Genetic; Glutamine; Goals; Image; Knock-out; Knowledge; Lipids; Liposomes; Membrane; Mexico; Microscopic; Modeling; Molecular; Molecular Conformation; Mutation; Mycobacterium tuberculosis; N-terminal; Pathogenesis; Phagocytes; Phagolysosome; Phagosomes; Play; Population; Prevention; Process; Proteins; Recombinants; Research; Research Design; Roentgen Rays; Role; Structure; Surface Plasmon Resonance; System; T-Lymphocyte; Therapeutic; Threonine; Time; Tuberculosis; Vaccines; Vesicle; Virulence; Virulence Factors; X-Ray Crystallography; design; innovation; insight; macrophage; molecular imaging; mutant; mycobacterial; novel; pathogen; single molecule; temporal measurement; therapeutic target; therapeutic vaccine; trafficking; tuberculosis treatment; two-photon; vaccine candidate; vaccine development

Title: Membrane interaction of Mycobacterium tuberculosis virulence factors PROJECT SUMMARY It is estimated that Mycobacterium tuberculosis (Mtb), a contagious and airborne bacterial pathogen, infects one-third of the world population and causes 1-2 million deaths each year. It is believed that initial Mtb infection occurs in alveolar macrophages. Mtb is internalized into the phagosome, where it penetrates the phagosomal membrane and translocates into the cytosol for replicating and cell-to-cell spreading. The cytosolic translocation is regarded as an important mechanism of Mtb pathogenesis. Two Mtb virulence factors, namely 6-kDal early antigenic target (MtbESAT6) and 10-kDal culture filtrate protein (MtbCFP10), are secreted out of Mtb as a heterodimer and have been implicated to play an essential role in Mtb cytosolic translocation. Genetic knockout of either esat-6 or cfp-10 results in defective cytosolic translocation and attenuated virulence. Our recent studies have suggested that MtbESAT-6 has an acidic-pH dependent pore- forming activity that is required for Mtb cytosolic translocation and virulence. However, the molecular mechanisms governing MtbESAT-6 pore formation and heterodimer dissociation are not clear. In the present proposal, using a variety of biochemical, microscopic, structural and cellular approaches, we will probe the dynamic process of MtbESAT-6 pore formation and determine the structure of the pore complex. We will also investigate the role of Nα-acetylation of MtbESAT-6 in acidification-induced heterodimer dissociation, a prerequisite for MtbESAT-6 to interact with the membrane. Studies designed in this grant proposal are aimed to fill the critical gap in our understanding of the MtbESAT-6-dependent molecular events during Mtb infection in alveolar macrophages and other phagocytes. Knowledge obtained from the proposed studies will facilitate the development of novel countermeasures, therapeutics and vaccines, against tuberculosis. !

标题：结核分枝杆菌毒力因子的膜相互作用 项目摘要 据估计，结核分枝杆菌（Mtb），一种传染性和空气传播的细菌病原体， 感染了世界三分之一的人口，每年造成1-2百万人死亡。据信，最初的结核分枝杆菌 感染发生在肺泡巨噬细胞中。结核分枝杆菌被内化到吞噬体中，在那里它穿透 在细胞质中，细胞通过吞噬体膜进入细胞质，并易位到细胞质中进行复制和细胞间扩散。的 胞质易位被认为是Mtb发病的重要机制。两种Mtb毒力 因子，即6-kDal早期抗原靶（MtbESAT 6）和10-kDal培养滤液蛋白（MtbCFP 10）， 作为异源二聚体分泌出Mtb，并被认为在Mtb细胞溶质中发挥重要作用。 易位esat-6或cfp-10的基因敲除导致缺陷性胞质易位， 减毒我们最近的研究表明，MtbESAT-6具有酸性pH依赖性孔， 形成Mtb胞质易位和毒力所需的活性。然而，分子 控制MtbESAT-6孔形成和异二聚体解离的机制尚不清楚。本 建议，使用各种生物化学，微观，结构和细胞的方法，我们将探讨 MtbESAT-6成孔的动力学过程，确定了孔复合体的结构。我们还将 研究MtbESAT-6的Nα-乙酰化在酸化诱导的异二聚体解离中的作用， MtbESAT-6与膜相互作用的先决条件。本研究计划旨在 填补了我们对Mtb感染期间MtbESAT-6依赖性分子事件理解的关键空白 在肺泡巨噬细胞和其他吞噬细胞中。从拟议研究中获得的知识将有助于 开发新的对抗结核病的对策、疗法和疫苗。 !