M tuberculosis Membrane Protein Pharmaceutical Targets

结核分枝杆菌膜蛋白药物靶点

• 批准号: 7561796
• 负责人: TIMOTHY A CROSS
• 金额: $ 176.58万
• 依托单位: FLORIDA STATE UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2009
• 资助国家: 美国
• 起止时间: 2009-08-20 至 2014-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7561796
• 关键词: tuberculosis; Membrane; Protein; Pharmaceutical; Targets

DESCRIPTION (provided by applicant): This Proposal is designed to address: 1) an important disease that needs novel drugs - no new drugs for Mycobacterium tuberculosis in 40 years and multi-drug resistant strains as well as extreme drug resistant strains are becoming more common; 2) the lack of structural information for an entire class of drug targets, the membrane proteins - less than 1% of known protein structures are membrane proteins, while 25 to 30% of the genome of most organisms code for membrane proteins - in addition, membrane proteins are more frequently effective drug targets than water-soluble proteins; 3) biological, functional and structural characterization of validated targets - we will characterize only those proteins that are essential for Mtb growth and by targeting membrane proteins, especially the outer membrane proteins, access to the drug targets will not require transport across the bacterial membranes. 4) a gap in screening technology - new small molecule screening technologies based on solution and solid state NMR spectroscopy will be developed specifically for membrane proteins. We have developed an Initial Target List from preliminary results and from literature on essential genes, virulence factors, identification of outer membrane proteins and numerous individual studies on specific potential targets. Some of these proteins are already validated as high potential pharmaceutical targets, these form a Prioritized Target List that will allow all of the Projects and Cores to initiate their efforts on the first day of funding. From biological function (Project 1) to assay development (Project 2) to structural characterization (Project 3) these activities will work closely together. Assays coupled with molecular structure will help establish structure-activity-relationships. Assay development will enable screening against small molecules important for understanding function and potentially important for structural studies. The assays we develop and the ligands we identify will fuel biological experiments designed to understand the life and infection cycle of Mtb. These ligands will be useful as lead compounds in drug discovery, and while this is beyond the scope of this Program, this team will protect the intellectual property for those who may want to pursue the development of drugs for these membrane protein targets. To accomplish these goals a unique team of investigators has been brought together with extensive knowledge of: Mycobacterium tuberculosis, essential Mtb genes, membrane protein physiology, molecular biology, biophysics, and structural characterization. The Program offers access to two of the premier NMR facilities in the world along with their expertise in methodology and technology development, in addition, the Team brings with it unique expression libraries of Mtb membrane proteins and the superb screening facilities and expertise of the Burnham Institute. PROJECT 1: TARGET IDENTIFICATION (NIEDERWEIS, M) PROJECT 1 DESCRIPTION (provided by applicant): More than 60% of all drug targets are membrane proteins. However, only one of the current antituberculous drugs, ethambutol, targets membrane proteins of M. tuberculosis, indicating that this vast potential is largely untapped for M. tuberculosis. The recent discovery of a new diarylquinoline drug that targets the ATP synthase of M. tuberculosis and exceeds the activities of the two main TB drugs isoniazid and rifampin provides proof of principle that this assumption is correct. Therefore, we have selected 11 out of approximately 800 putative inner membrane proteins of M. tuberculosis, which are essential for growth of M. tuberculosis in vitro or in mice. These proteins were selected to cover a broad variety of functions, such as transport of essential nutrients, cell division, export of proteins and cell wall and lipid biosynthesis. Furthermore, they are sufficiently small to be amenable to current solid-state NMR methods. Outer membrane proteins offer the tremendous advantage as drug targets that inhibitors may not need to cross the outer membrane which is an extremely efficient permeability barrier in mycobacteria. In addition, they are likely to represent novel drug targets because they do not appear to show any similarity to other proteins. Therefore, we included seven putative outer membrane proteins in our list of initial targets, six of which have no known function. The goal of this project is to validate the potential of the 18 selected membrane proteins as drug targets, to elucidate the physiological function of the six proteins with no known homologs and to identify putative interaction partners for some of these proteins.

描述（申请人提供）：本提案旨在解决：1）需要新药的重要疾病——结核分枝杆菌40年没有新药，多重耐药菌株以及极端耐药菌株变得越来越普遍; 2) 缺乏整类药物靶点膜蛋白的结构信息——已知蛋白质结构中不到 1% 是膜蛋白，而大多数生物体的基因组中有 25% 至 30% 编码膜蛋白——此外，膜蛋白比水溶性蛋白更常成为有效的药物靶点； 3) 已验证靶标的生物学、功能和结构表征 - 我们将仅表征 Mtb 生长所必需的那些蛋白质，并且通过靶向膜蛋白，特别是外膜蛋白，获得药物靶标将不需要跨细菌膜运输。 4）筛选技术的差距——将专门针对膜蛋白开发基于溶液和固态核磁共振波谱的新型小分子筛选技术。我们根据初步结果和有关基本基因、毒力因子、外膜蛋白鉴定的文献以及针对特定潜在目标的大量单独研究制定了初步目标列表。其中一些蛋白质已经被验证为高潜力的药物靶点，这些形成了优先目标列表，这将使所有项目和核心在资助的第一天就开始努力。从生物功能（项目 1）到测定开发（项目 2）再到结构表征（项目 3），这些活动将紧密结合在一起。与分子结构相结合的测定将有助于建立结构-活性关系。检测方法的开发将能够筛选小分子，这对于理解功能很重要，并且对于结构研究也可能很重要。我们开发的检测方法和我们确定的配体将为旨在了解结核分枝杆菌的生命和感染周期的生物实验提供动力。这些配体将可用作药物发现中的先导化合物，虽然这超出了本计划的范围，但该团队将为那些可能想要开发这些膜蛋白靶点药物的人保护知识产权。为了实现这些目标，我们组建了一个独特的研究团队，他们拥有以下方面的广泛知识：结核分枝杆菌、必需的 Mtb 基因、膜蛋白生理学、分子生物学、生物物理学和结构表征。该计划提供了使用世界上两个顶级 NMR 设施的机会以及他们在方法和技术开发方面的专业知识，此外，该团队还带来了独特的 Mtb 膜蛋白表达库以及伯纳姆研究所的一流筛选设施和专业知识。 项目 1：目标识别（NIEDERWEIS，M） 项目 1 描述（由申请人提供）：超过 60% 的药物靶点是膜蛋白。然而，目前的抗结核药物中只有一种乙胺丁醇靶向结核分枝杆菌的膜蛋白，这表明结核分枝杆菌的这一巨大潜力在很大程度上尚未开发。最近发现了一种新的二芳基喹啉药物，它以结核分枝杆菌的 ATP 合酶为靶点，其活性超过了两种主要结核病药物异烟肼和利福平的活性，这从原理上证明了这一假设的正确性。因此，我们从大约 800 种假定的结核分枝杆菌内膜蛋白中选择了 11 种，它们对于结核分枝杆菌在体外或小鼠体内的生长至关重要。这些蛋白质被选择来涵盖多种功能，例如必需营养素的运输、细胞分裂、蛋白质和细胞壁的输出以及脂质生物合成。此外，它们足够小，适合当前的固态核磁共振方法。外膜蛋白作为药物靶点具有巨大的优势，抑制剂可能不需要穿过外膜，而外膜是分枝杆菌中极其有效的渗透性屏障。此外，它们很可能代表新的药物靶点，因为它们似乎与其他蛋白质没有任何相似性。因此，我们在初始目标列表中纳入了七种假定的外膜蛋白，其中六种没有已知的功能。该项目的目标是验证 18 种选定的膜蛋白作为药物靶点的潜力，阐明六种没有已知同源物的蛋白质的生理功能，并确定其中一些蛋白质的假定相互作用伙伴。