Evaluating the Role of L,D-Transpeptidases in Mycobacterial Pathogenesis

评估 L,D-转肽酶在分枝杆菌发病机制中的作用

• 批准号: 10197831
• 负责人: Kimberly Elizabeth Beatty
• 金额: $ 48.64万
• 依托单位: OREGON HEALTH & SCIENCE UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2020
• 资助国家: 美国
• 起止时间: 2020-06-18 至 2025-11-30
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10197831
• 关键词: Amoxicillin; Anabolism; Antibiotics; Biochemical; Biology; Cell Wall; Cells; Chemicals; Clavulanate; Clinical; Combined Modality Therapy; Communicable Diseases; Critical Illness; Disease; Drug Targeting; Drug resistance; Drug resistance in tuberculosis; Enzymes; Exposure to; Gel; Genus Mycobacterium; Goals; Human; Infection; Lung; Lung diseases; Meropenem; Microscopy; Molecular; Molecular Probes; Monitor; Monobactams; Mycobacterium Infections; Mycobacterium abscessus; Mycobacterium tuberculosis; National Institute of Allergy and Infectious Disease; Pathogenesis; Patients; Penicillin-Binding Proteins; Peptidoglycan; Peptidyltransferase; Pharmaceutical Preparations; Predisposition; Process; Proteins; Regulation; Reporting; Research; Role; Speed; Structure; Sulfatases; Technology; Therapeutic; Treatment Protocols; Tuberculosis; United States; Work; base; beta-Lactams; clinically relevant; cost; crosslink; drug development; effective therapy; inhibitor/antagonist; insight; molecular imaging; mycobacterial; non-tuberculosis mycobacteria; novel therapeutics; pathogen; programs; resistant strain; small molecule; spatiotemporal; success; tool; treatment strategy; tuberculosis drugs

Project Summary Tuberculosis (TB) killed 1.3 million people in 2017 and is the most deadly infectious disease in the world. Infections caused by drug-susceptible Mycobacterium tuberculosis (Mtb) can be cured. But treatment regimens are long, requiring at least 6 months of therapy with multiple drugs. TB has become increasingly difficult to treat due to the global spread of drug resistant strains. Such strains account for at least 5% of infections, and the cure rate for those patients is low. New drugs are urgently needed to treat drug-resistant strains, but drug development is a slow and costly process. But what if clinically-approved β-lactam antibiotics could be repurposed to treat TB and drug resistant TB? This would significantly speed up patient access to new therapies. Since the 1990s, there have been occasional reports of TB infections responding to β-lactam antibiotics. For example, amoxicillin/clavulanate and meropenem/clavulanate have been used successfully to treat patients with drug resistant TB. β-lactam antibiotics target enzymes in the cells wall. Targets include penicillin-binding proteins (PBPs) and the recently discovered L,D-transpeptidases (LDTs). Both classes of enzyme are critical to survival because they maintain the structure and rigidity of peptidoglycan in the bacterial cell wall. We propose to develop new molecular probes to identify and validate β-lactam drug susceptibility in mycobacteria. Our approach facilitates monitoring multiple PBPs and LDTs at once, enabling a comprehensive examination of these enzymes. We will detect enzymes in protein gel-resolved lysates using activity-based probes (ABPs) derived from the major classes of β-lactam drugs. Identifying drugs with activity against dormant mycobacteria is a high-priority. Therefore, in Aim 1, we will use ABPs to profile the regulation of PBPs and LDTs in dormant, reactivating, and actively-replicating Mtb. In Aim 2, we will determine the drug selectivity and inhibitor profiles for the Mtb PBPs and LDTs following exposure to clinically-approved β-lactam antibiotics. In Aim 3, we will investigate the spatio-temporal regulation of the LDTs. In Aim 4, we will extend our findings to a second high-priority mycobacterial pathogen: M. abscessus. Upon successful completion of this project, we will have an effective approach for assessing the susceptibility of mycobacterial strains to treatment with β-lactams and combination therapies. We anticipate that our findings will have a positive impact on selecting effective therapies for patients infected with Mtb or M. abscessus.

项目摘要 结核病（TB）在2017年造成130万人死亡，是世界上最致命的传染病。 由药物敏感的结核分枝杆菌（Mtb）引起的感染可以治愈。但治疗 疗程较长，需要至少6个月的多种药物治疗。结核病日益成为 由于耐药菌株的全球传播而难以治疗。这些菌株占至少5%， 这些患者的治愈率很低。迫切需要新的药物来治疗耐药 菌株，但药物开发是一个缓慢和昂贵的过程。 但是，如果临床批准的β-内酰胺抗生素可以重新用于治疗结核病和耐药结核病呢？ 这将大大加快患者获得新疗法的速度。自20世纪90年代以来， 偶尔报告对β-内酰胺类抗生素有反应的结核感染。例如，阿莫西林/克拉维酸 和美罗培南/克拉维辛已成功用于治疗耐药结核病患者。β-内酰胺 抗生素的目标是细胞壁中的酶。靶点包括青霉素结合蛋白（PBP）和 最近发现的L，D-转肽酶（LDTs）。这两类酶对生存都至关重要，因为它们 维持细菌细胞壁中肽聚糖的结构和刚性。 我们建议开发新的分子探针来鉴定和验证β-内酰胺类药物的敏感性， 分枝杆菌我们的方法有助于同时监测多个PBPs和LDTs， 对这些酶进行全面检测。我们将检测蛋白质凝胶溶解裂解物中的酶， 基于活性的探针（ABP）来自主要类别的β-内酰胺类药物。识别具有活性的药物 对抗休眠分枝杆菌是当务之急因此，在目标1中，我们将使用ABP来分析 PBP和LDT在休眠，再活化和活跃复制的结核分枝杆菌的调节。在目标2中，我们将 确定暴露于以下物质后Mtb PBP和LDT的药物选择性和抑制剂概况： 临床批准的β-内酰胺抗生素。在目标3中，我们将研究 LDTs。在目标4中，我们将把我们的发现扩展到第二个高优先级的分枝杆菌病原体：M。你好 待这项计划成功完成后，我们便会有一个有效的方法， 分枝杆菌菌株对β-内酰胺类药物治疗和联合治疗的敏感性。我们预计 我们的研究结果将对选择有效的治疗感染结核分枝杆菌的患者产生积极的影响， M.你好