Function of SecA2 in Mycobacterium tuberculosis protein export

SecA2在结核分枝杆菌蛋白输出中的功能

• 批准号: 7456328
• 负责人: CAROLYN M TESCHKE
• 金额: $ 7.46万
• 依托单位: UNIVERSITY OF CONNECTICUT STORRS
• 依托单位国家: 美国
• 财政年份: 2007
• 资助国家: 美国
• 起止时间: 2007-07-01 至 2011-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7456328
• 关键词: AIDS/HIV problem; ATP Hydrolysis; ATP phosphohydrolase; Antibiotics; Attenuated; Bacteria; Binding; Biochemical; Biological Assay; Cause of Death; Cells; Data; Depth; Development; Disease; Drug Delivery Systems; Drug resistance; Environment; Escherichia coli; Essential Drugs; Future; Genus Mycobacterium; Goals; Grant; Host Defense Mechanism; Hydrolysis; In Vitro; Membrane; Monitor; Motor; Multi-Drug Resistance; Mycobacterium tuberculosis; Nature; Pathogenesis; Pathway interactions; Pharmaceutical Preparations; Physiology; Population; Protein Export Pathway; Protein Secretion; Proteins; Rate; Reaction; Resistance; Rifampin; Species Specificity; Techniques; Time; Tuberculosis; Virulence; Work; analytical ultracentrifugation; antimicrobial; design; drug development; fight against; in vitro Assay; in vivo; inhibitor/antagonist; isoniazid; killings; microorganism; monomer; mortality; pathogen; pathogenic bacteria; research study

DESCRIPTION (provided by applicant): Mycobacterium tuberculosis is the causative agent for the disease tuberculosis (TB). TB kills about 2 million people each year and around a third of the world's population is infected with TB. TB newly infects nearly 1% of the world's population each year. TB is a leading cause of death among people with HIV/AIDS. Though TB can normally be treated with antibiotics, a serious problem in the worldwide fight against TB is the emergence of multi-drug resistant strains of TB. In order to develop logical targets for new drugs, the physiology of Mycobacteria must be better understood. Pathogenic bacteria such as M. tuberculosis secrete proteins in order to evade host defense mechanisms and survive in host cells, making protein export a logical drug target. The long-term goal of this work is to characterize the Sec-dependent protein export of M. tuberculosis. The Sec-dependent translocation pathway that involves dimeric SecA and SecYEG is used for export of many proteins. SecA, an essential protein found in all bacteria, is an ATPase and provides the energy used in the export of proteins through the SecYEG membrane translocation machinery. Recently, several pathogenic microorganisms, including M. tuberculosis, have been discovered to carry two SecA proteins, SecA1 and SecA2. SecA1 is essential for general protein export while SecA2 is specific for secretion of some virulence proteins. However, why these microorganisms require two SecA proteins is not understood. Because SecA proteins are generally specific to a particular microorganism, SecA1 and SecA2 provide good targets for drug development. Therefore, we propose to characterize the function of each of these SecA proteins in protein export from M. tuberculosis. We will characterize the SecA proteins using biochemical and biophysical techniques including ATPase binding and hydrolysis assays, analytical ultracentrifugation to monitor subunit associations, and develop in vitro membrane binding and translocation assays for M. tuberculosis proteins. The specific questions for this R03 grant are: 1). Do SecA1 and SecA2 possess similar abilities to bind and hydrolyze ATP?; 2) Do SecA1 and SecA2 interact with each other?; and 3.) How do SecA1 and SecA2 interact with membrane translocation machinery? These experiments are designed to initiate an in depth characterization of the function of both SecA proteins in M. tuberculosis. Mycobacterium tuberculosis is the causative agent for the disease tuberculosis (TB). TB kills about 2 million people each year and around a third of the world's population is infected with TB. TB newly infects nearly 1% of the world's population each year. TB is a leading cause of death among people with HIV/AIDS. Though TB can normally be treated with antibiotics, a serious problem in the world-wide fight against TB is the emergence of multi-drug resistant strains of TB. In order to develop logical targets for new drugs, the physiology of Mycobacteria must be better understood.

描述（由申请人提供）：结核分枝杆菌是疾病结核病（TB）的病因。 TB每年杀死约200万人，大约三分之一的人口感染了结核病。 TB每年新近感染世界近1％的人口。结核病是艾滋病毒/艾滋病患者中死亡的主要原因。尽管通常可以用抗生素治疗结核病，但全球与结核病的斗争中的一个严重问题是TB多药抗性菌株的出现。为了开发新药的逻辑靶标，必须更好地理解分枝杆菌的生理。致病细菌（例如结核分枝杆菌）分泌蛋白质，以逃避宿主的防御机制并在宿主细胞中生存，从而使蛋白质导出成为逻辑的药物靶标。这项工作的长期目标是表征结核分枝杆菌的SEC依赖性蛋白质出口。涉及二聚体SECA和SECYEG的SEC依赖性易位途径用于导出许多蛋白质。 SECA是所有细菌中发现的必需蛋白质，是一种ATPase，可通过Secyeg膜易位机械提供用于导出蛋白质的能量。最近，已经发现了几种病原性微生物，包括结核分枝杆菌，可携带两种SECA蛋白SECA1和SECA2。 SECA1对于一般蛋白质导出至关重要，而SECA2对于某些毒力蛋白的分泌特异性。但是，为什么不了解这些微生物需要两种SECA蛋白。由于SECA蛋白通常针对特定的微生物，因此SECA1和SECA2为药物开发提供了良好的靶标。因此，我们建议表征这些SECA蛋白在结核分枝杆菌中的蛋白质中的功能。我们将使用生化和生物物理技术（包括ATPase结合和水解测定法），分析性超速离心以监测亚基关联，并开发用于结核分枝杆菌蛋白的体外膜结合和易位测定法，来表征SECA蛋白。此R03赠款的具体问题是：1）。 Seca1和seca2是否具有结合和水解ATP的类似能力？ 2）seca1和seca2是否相互作用？ 3.）SECA1和SECA2如何与膜易位机械相互作用？这些实验旨在启动对结核分枝杆菌中两种SECA蛋白功能的深入表征。结核分枝杆菌是疾病结核病（TB）的病因。 TB每年杀死约200万人，大约三分之一的人口感染了结核病。 TB每年新近感染世界近1％的人口。结核病是艾滋病毒/艾滋病患者中死亡的主要原因。尽管通常可以用抗生素治疗结核病，但全球与结核病斗争中的一个严重问题是TB多药抗性菌株的出现。为了开发新药的逻辑靶标，必须更好地理解分枝杆菌的生理。