Structural homeostasis and the assembly of a bacterial nanomachine

结构稳态和细菌纳米机器的组装

• 批准号: 9098739
• 负责人: Daniel B Kearns
• 金额: $ 30.27万
• 依托单位: TRUSTEES OF INDIANA UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2010
• 资助国家: 美国
• 起止时间: 2010-07-15 至 2019-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9098739
• 关键词: Animal Model; Anti-Bacterial Agents; Architecture; Area; Bacillus subtilis; Bacteria; Bacterial Infections; Behavior; Binding; Binding Sites; Biochemistry; Biology; Cell division; Cell surface; Cells; Complex; Coupled; Cytoplasm; Disease; Environment; Evolution; Face; Feedback; Filament; Flagella; Flagellin; Gammaproteobacteria; Gene Expression; Genetic; Genetic Models; Goals; Health; Homeostasis; Infection; Learning; Length; Measures; Microbial Biofilms; Microscopy; Molecular Chaperones; Mutate; Mutation; Pharmaceutical Chemistry; Pharmaceutical Preparations; Phylogenetic Analysis; Physiology; Pilum; Post-Transcriptional Regulation; Proteins; RNA Binding; RNA-Binding Proteins; Regulation; Regulator Genes; Research; Resolution; Role; Runaway; Small RNA; Structural Genes; Structure; System; Therapeutic; Transcript; Transcriptional Regulation; Translations; Trees; Virulence; Work; cell envelope; combat; forward genetics; inhibitor/antagonist; insight; mutant; nanomachine; pathogen; pathogenic bacteria; prevent; stoichiometry; structural biology

 DESCRIPTION (provided by applicant): Bacteria build elaborate nanomachines on their cell surface to interact with their environment and cause disease. Each machine must be assembled from specific parts, in the proper order, and in precise amounts. Here we propose to study the mechanism by which a structural protein of the flagellar filament, Hag, homeostatically controls its own synthesis and governs its own assembly in Bacillus subtilis. Hag is part of a three-node negative feedback loop including FliW and the highly conserved post-transcriptional regulator of virulence gene expression, CsrA. We will determine the mechanism by which FliW antagonizes CsrA and we will determine the NMR solution structures of CsrA and FliW, separately and in complex. We will study an internal feedback loop in which the flagellin transcript helps maintain CsrA-FliW stoichiometry. We will measure the cytological parameters of filament length and elongation rate, determine how feedback regulation contributes to each parameter, and explore homeostatic regulation in another structural protein, the FlgE flagellar hook subunit. Our work will establish new paradigms for the post-transcriptional regulation of nanomachine assembly and provide new insights into the origin and evolution of virulence gene regulators. We will advance B. subtilis as a model organism for flagellar research and we use B. subtilis as a genetic platform for the expression and study of heterologous regulators from distantly related pathogenic bacteria. Finally, we have isolated drugs that antagonize CsrA when added to whole cells will characterize the anti-CsrA drugs as candidate antibacterial therapeutics.

 描述（由申请人提供）：细菌在其细胞表面构建复杂的纳米机器，以与环境相互作用并引起疾病。每台机器都必须由特定部件以正确的顺序和精确的数量组装而成。枯草芽孢杆菌中鞭毛丝的结构蛋白 Hag 稳态控制其自身合成并控制其自身组装，Hag 是包括 FliW 和毒力基因表达的高度保守的转录后调节因子 CsrA 我们将确定 FliW 拮抗 CsrA 的机制，并且我们将单独和复杂地确定 CsrA 和 FliW 的 NMR 溶液结构。鞭毛蛋白转录物有助于维持CsrA-FliW化学计量，我们将测量丝长度和伸长率的细胞学参数，确定如何反馈调节。我们的工作将为每个参数做出贡献，并探索另一种结构蛋白 FlgE 鞭毛钩子亚基的稳态调节，并为纳米机器组装的转录后调节建立新的范例，并为毒力基因调节剂的起源和进化提供新的见解。将推动枯草芽孢杆菌作为鞭毛研究的模式生物，我们使用枯草芽孢杆菌作为遗传平台来表达和研究远缘致病菌的异源调节因子最后，我们分离出了药物。当添加到全细胞中时拮抗 CsrA 的药物将使抗 CsrA 药物成为候选抗菌疗法。