Mycobacterium Tuberculosis Cell Wall Assembly

结核分枝杆菌细胞壁组装

• 批准号: 8938582
• 负责人: Mary Jackson
• 金额: $ 18.75万
• 依托单位: COLORADO STATE UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2015
• 资助国家: 美国
• 起止时间: 2015-07-01 至 2017-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8938582
• 关键词: Actins; Address; Anabolism; Anti-Bacterial Agents; Antibiotics; Antitubercular Agents; Bacillus (bacterium); Bacillus subtilis; Bacteria; Biochemical; Biological Assay; Cell Wall; Cell division; Cells; Chemistry; Collaborations; Colorado; Complex; Contracts; Corynebacterium glutamicum; Development; Enzymes; Family; Future; Gene Cluster; Genes; Genetic; Genome; Genus Mycobacterium; Gram-Positive Bacteria; Growth; Homologous Gene; In Vitro; Incidence; Individual; Institutes; Japan; Knock-out; Knowledge; Ligase; Link; Maps; Mediating; Molecular; Multi-Drug Resistance; Muramidase; Mus; Mycobacterium tuberculosis; Mycobacterium tuberculosis H37Rv; N-acetylglucopyranosylamine; National Institute of Allergy and Infectious Disease; Parents; Pathway interactions; Peptidoglycan; Phenotype; Physiological; Physiological Processes; Physiology; Play; Predisposition; Proteins; Recombinants; Resistance; Role; Shapes; Site; Staphylococcus aureus; Structure; Teichoic Acids; Testing; Therapeutic; Therapeutic Studies; Tokyo; Transferase; Universities; Validation; Virulence; arabinogalactan; base; cell assembly; cell envelope; design; in vitro Assay; in vivo; inhibitor/antagonist; innovation; inorganic phosphate; insight; knock-down; lipoteichoic acid; macromolecule; microbial; mutant; mycobacterial; novel; novel strategies; pathogen; permissiveness; programs; public health relevance; research study; resistant strain; retinal rods; scaffold; screening; translocase; tuberculosis drugs

 DESCRIPTION (provided by applicant): The cell envelope of Mycobacterium tuberculosis (Mtb) is the basis of many of the physiological and pathogenic features of this bacterial pathogen and the site of susceptibility and resistance to many anti- tuberculosis drugs. In spite of being Gram-positive bacteria, mycobacteria are unique in having a cell wall devoid of (lipo)teichoic acids and instead containing a heteropolysaccharide known as the arabinogalactan (AG) covalently attached to peptidoglycan (PG). To this date, the cell wall ligase(s) responsible for the covalent attachment of these two macromolecules has/have defied definition. Despite the fundamental structural differences that exist between AG and wall teichoic acids (WTA), the structure of the unit linking AG to PG in mycobacteria shares similarities with the linker involved in the covalent attachment of WTA to PG in many Gram-positive bacteria. Enzymes of the widespread LytR-Cps2A-Psr (LCP) family were recently identified as the likely ligases mediating WTA-PG attachment in Bacillus subtilis and Staphylococcus aureus. We identified three LCP-like proteins in the genome of Mtb H37Rv, one of them mapping to an AG biosynthetic gene cluster. We here propose to use a combination of genetic and biochemical approaches to determine whether these three LCP homologs are the long sought mycobacterial cell wall ligases and to define their therapeutic potential. In particula, we will test whether two novel antibacterial compounds, caprazamycin B and CPZEN-45, products of a collaboration with the Institute of Microbial Chemistry (BIKAKEN, Tokyo, Japan) that inhibit mechanistically similar enzymes in mycobacterial cell wall assembly (MraY and WecA, respectively) may represent promising scaffolds for the future development of inhibitors targeting the assembly of the mycobacterial cell wall. Similar to the situation with WTA ligases, i is likely that the ligase(s) of Mtb interact(s) with other wall proteins to coordinate cell wall synthesis with cell elongation and cell division. The characterization of Mtb's ligase(s) therefore also represents an important first step toward the elucidation of this key aspect of the physiology of mycobacteria and the future design of innovative therapeutic strategies aimed at targeting cell elongation and division.

 描述（由申请人提供）：结核分枝杆菌（Mtb）的细胞包膜是该细菌病原体的许多生理和致病特征的基础，也是对许多抗结核药物的敏感性和耐药性的部位，尽管是革兰氏菌。 - 阳性细菌，分枝杆菌的独特之处在于其细胞壁不含（脂）磷壁酸，而是含有称为阿拉伯半乳聚糖 (AG) 与肽聚糖 (PG) 共价连接 迄今为止，尽管 AG 和壁连接酶之间存在根本的结构差异，但负责这两个大分子共价连接的细胞壁连接酶仍无法定义。 (s) 酸 (WTA)，分枝杆菌中连接 AG 和 PG 的单元结构与许多革兰氏阳性菌中参与 WTA 和 PG 共价连接的连接体具有相似之处最近，我们在枯草芽孢杆菌和金黄色葡萄球菌（Mtb H37Rv）的基因组中鉴定出了三种 LCP 样蛋白，即广泛存在的 LytR-Cps2A-Psr (LCP) 家族的酶。将它们映射到 AG 生物合成基因簇，我们在此建议使用遗传和生化方法相结合来确定这三种 LCP 是否同源。是长期寻求的分枝杆菌细胞壁连接酶，为了确定它们的治疗潜力，我们将测试两种新型抗菌化合物卡普拉霉素 B 和 CPZEN-45，它们是与微生物化学研究所（BIKAKEN，东京，日本）合作的产品。 ）抑制分枝杆菌细胞壁组装中机制相似的酶（分别为MraY和WecA）可能代表未来有希望的支架开发针对分枝杆菌细胞壁组装的抑制剂 与 WTA 连接酶的情况类似，Mtb 连接酶可能与其他壁蛋白相互作用，以协调细胞壁合成与细胞伸长和细胞分裂。因此，Mtb 连接酶的表征 也代表着朝着阐明生理学这一关键方面迈出了重要的第一步 分枝杆菌的研究以及针对细胞伸长和分裂的创新治疗策略的未来设计。