Characterization of Pupylation in Mycobacterium tuberculosis

结核分枝杆菌化脓的特征

• 批准号: 8038748
• 负责人: Katerina Heran Darwin
• 金额: $ 38.03万
• 依托单位: NEW YORK UNIVERSITY SCHOOL OF MEDICINE
• 依托单位国家: 美国
• 财政年份: 2010
• 资助国家: 美国
• 起止时间: 2010-12-01 至 2015-11-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8038748
• 关键词: Antibiotics; Antitubercular Agents; Bacteria; Biochemical; Biochemistry; Biological; Biology; Cause of Death; Complex; Coupled; Data; Development; Drug resistance; Enzymatic Biochemistry; Enzymes; Eukaryota; Extreme drug resistant tuberculosis; Foundations; Future; Genetic; Genus Mycobacterium; Glutamates; Glutamine; Goals; Growth; In Vitro; Ligase; Ligation; Lysine; Mediating; Modeling; Molecular; Molecular Chaperones; Mus; Mycobacterium tuberculosis; Nitric Oxide; Pathogenesis; Pathway interactions; Post-Translational Protein Processing; Process; Production; Prokaryotic Cells; Proteins; Resistance; Shapes; Specificity; Structure; System; Techniques; Toxic effect; Tuberculosis; Ubiquitin; Ubiquitin Like Proteins; Virulence; base; deamidation; drug development; factor A; interest; killings; macrophage; multicatalytic endopeptidase complex; mutant; mycobacterial; novel; protein degradation; pup; tuberculosis drugs; tuberculosis treatment; ubiquitin ligase

DESCRIPTION (provided by applicant): Tuberculosis kills about 2 million people globally every year. A key defense against Mycobacterium tuberculosis (Mtb) infections is the production of nitric oxide (NO) by macrophages. Although NO controls Mtb growth, it rarely sterilizes the bacterium from the host, suggesting Mtb has mechanisms to resist NO toxicity. The Mtb proteasome is one such mechanism that is required for resistance to NO as well as causing death in mice. Thus, we are interested in targeting the proteasome and its associated factors for drug development. The proteasome is a multi-subunit, barrel shaped complex that degrades proteins. We found that the proteins Mpa and PafA are required for protein degradation: Mpa is thought to chaperone proteins into the proteasome core and PafA appears to be required for the attachment of a prokaryotic ubiquitin-like protein (Pup) onto substrates targeted for destruction. Pup represents the first known post-translational small protein modifier identified in any prokaryote. Little is known about how Pup is conjugated to its target substrates thus we propose to identify and characterize all proteins required for "pupylation" using genetic, biochemical and molecular biological techniques. In addition, we have recently discovered pupylation is reversible, thus we are in the process of characterizing the "depupylation" pathway. The elucidation of the Pup-proteasome sytem of Mtb will hopefully lay the foundation for the discovery and characterization of other posttranslational modification systems in all bacteria. Furthermore, these enzymes may represent new targets for the development of anti- tuberculosis drugs. PUBLIC HEALTH RELEVANCE: Tuberculosis therapy takes 6-9 months, a problem that leads to decreased compliance for taking antibiotics and increased chances of developing drug-resistance. The rise of extensively drug resistant (XDR) strains of M. tuberculosis has become a great public concern as it has recently made headlines in the popular press. Thus the new treatments for tuberculosis are needed now, and the pupylation pathway may provide new targets for drug development.

描述(申请人提供)：全球每年约有200万人死于结核病。对抗结核分枝杆菌(Mtb)感染的关键防御措施是巨噬细胞产生一氧化氮(NO)。虽然NO控制着结核分枝杆菌的生长，但它很少杀灭宿主中的细菌，这表明结核分枝杆菌具有抵抗无毒性的机制。Mtb蛋白酶体是抵抗NO以及导致小鼠死亡所必需的一种机制。因此，我们有兴趣将蛋白酶体及其相关因子作为药物开发的靶点。蛋白酶体是一种多亚单位的桶形复合体，可降解蛋白质。我们发现，蛋白质降解需要蛋白MPA和PAFA：MPA被认为是蛋白酶体核心的伴侣蛋白，而PAFA似乎是将原核泛素样蛋白(PUP)附着到靶向破坏的底物上所必需的。PUP是在原核生物中发现的第一个已知的翻译后小蛋白修饰物。关于Pup是如何与其目标底物结合的，我们知之甚少，因此我们建议使用遗传、生物化学和分子生物学技术来鉴定和表征“化蛹”所需的所有蛋白质。此外，我们最近发现，化蛹是可逆的，因此我们正在表征“去化蛹”的途径。Mtb的Pup-蛋白酶体系统的阐明有望为发现和鉴定所有细菌中的其他翻译后修饰系统奠定基础。此外，这些酶可能是抗结核药物开发的新靶点。 公共卫生相关性：结核病治疗需要6-9个月，这一问题导致服用抗生素的依从性降低，并增加了产生抗药性的机会。广泛耐药(XDR)结核分枝杆菌菌株的崛起已成为公众的极大关注，因为它最近成为大众媒体的头条新闻。因此，现在需要新的治疗结核病的方法，而髓化途径可能为药物开发提供新的靶点。