Structural parameters of flagellar rod and filament assembly in Bacillus subtilis

枯草芽孢杆菌鞭毛杆和丝组装的结构参数

• 批准号: 9327547
• 负责人: Andrew Michael Burrage
• 金额: $ 5.67万
• 依托单位: TRUSTEES OF INDIANA UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2017
• 资助国家: 美国
• 起止时间: 2017-06-01 至 2019-05-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9327547
• 关键词: Address; Animal Model; Antibiotic Therapy; Area; Bacillus (bacterium); Bacillus subtilis; Bacteria; Bacterial Proteins; Basal Plate; Biochemical; Biological Assay; Biological Process; Biomedical Engineering; Biotechnology; Cell membrane; Cell physiology; Cells; Cellular biology; Clinical; Complex; Data; Disease; Electron Microscopy; Ensure; Environment; Escherichia coli; Filament; Flagella; Genetic; Genetic Techniques; Genetic Transcription; Gram-Positive Bacteria; Growth; Individual; Investigation; Label; Length; Maintenance; Measures; Mediating; Membrane; Methods; Microscopy; Modeling; Molecular; Morphology; Motor; Movement; Organism; Pathogenesis; Pathogenicity; Peptidoglycan; Proteins; Regulation; Reporting; Research; Salmonella typhimurium; Staining method; Stains; Structure; System; Techniques; Thick; Time; Translations; Variant; Virulence; Virulence Factors; cell motility; experimental study; extracellular; fitness; forward genetics; insight; kinetosome; knowledge base; mutant; nanomachine; novel; periplasm; polymerization; prevent; repaired; retinal rods

PROJECT SUMMARY Bacteria assemble large extracellular complexes called nanomachines to differentially interact with their environment. Nanomachines enact specific functions, including substrate secretion, cell motility, and pathogenesis. The regulation and structural composition of bacterial protein nanomachines is inherently complex. One such nanomachine, the flagellar apparatus, is critical for bacterial motility, and its assembly is highly ordered. Many regulatory systems are in place to ensure that proper assembly of the flagella occurs both spatially and temporally. Many studies investigate the composition of the flagellar structure as well as how the host regulates transcription and translation of its various components. However, less is known regarding the systems in place controlling accurate assembly of the flagellum. One of the major components of the flagellum is the extracellular filament, which is responsible for generating thrust to mobilize the cell. The majority of studies focusing on filament assembly use the Gram- negative organisms Salmonella typhimurium and Escherichia coli. Investigations suggest that these two closely related organisms maintain distinct mechanisms regulating filament length, as well as repair. Whether the precise regulation of filament length is necessary for efficient motility across all species is unknown. Using the genetically tractable, Gram-positive model bacterium Bacillus subtilis, we propose to determine the mechanisms employed by this organism to control filament growth and length, as well as whether filament repair occurs. Additionally, mechanisms regulating the length of the flagellar rod spanning from the membrane-bound flagellar motor to the extracellular filament in B. subtilis is unknown. Four proteins putatively make up the B. subtilis rod, but their order of assembly is currently unknown. Further, the rod must precisely traverse a large distance in both Gram-negative (periplasm) and Gram-positive (peptidoglycan) organisms to initiate assembly of the flagellar filament. Thus, the cell must regulate rod length to accurately span these depths. Although studies in the Gram-negative S. typhimurium show rod length is determined via interaction with the outer membrane, a lack of an outer membrane in Gram-positive organisms indicates a different mechanism is in place. We will identify the structural composition of the rod and determine the components controlling rod length. The aims of this proposal and experiments suggested focus on the structural organization of the flagellar rod and filament, specifically to: (i) assess the cell mechanisms controlling flagellar filament length and elongation, and (ii) define the components that make up the rod and determine the regulation of its length and assembly. We will address the proposed experiments using genetic, biochemical, and cell biology techniques. Overall, these aims intend to promote our understanding of bacterial nanomachine regulation and their contributions to cell physiology and fitness.

项目概要 细菌组装称为纳米机器的大型细胞外复合物，以与细菌进行不同的相互作用 环境。纳米机器具有特定的功能，包括底物分泌、细胞运动和 发病。细菌蛋白纳米机器的调控和结构组成本质上是 复杂的。鞭毛装置就是这样一种纳米机器，它对于细菌的运动至关重要，其组装过程是 高度有序。许多监管系统都已到位，以确保鞭毛的正确组装发生在 空间上和时间上。许多研究调查了鞭毛结构的组成以及如何 宿主调节其各种成分的转录和翻译。然而，关于 控制鞭毛精确组装的系统。 鞭毛的主要成分之一是细胞外丝，它负责 产生推力来动员细胞。大多数关注灯丝组装的研究都使用 Gram- 阴性菌为鼠伤寒沙门氏菌和大肠杆菌。调查显示，两人关系密切 相关生物体维持着调节丝长度和修复的独特机制。无论是 精确调节丝长度对于所有物种的有效运动是否必要尚不清楚。使用 遗传上易于处理的革兰氏阳性模型细菌枯草芽孢杆菌，我们建议确定其机制 该生物体利用它来控制细丝的生长和长度，以及是否发生细丝修复。 此外，调节从膜结合的鞭毛杆长度的机制 枯草芽孢杆菌中鞭毛对细胞外丝的运动尚不清楚。据推测，B 蛋白由四种蛋白质组成。 枯草杆菌棒，但它们的组装顺序目前未知。此外，杆必须精确地穿过一个大的 革兰氏阴性（周质）和革兰氏阳性（肽聚糖）生物体中启动组装的距离 鞭毛丝。因此，细胞必须调节杆的长度以准确地跨越这些深度。虽然 对革兰氏阴性鼠伤寒沙门氏菌的研究表明，杆状长度是通过与外部相互作用来确定的。 膜，革兰氏阳性生物体缺乏外膜表明存在不同的机制。 我们将确定杆的结构组成并确定控制杆长度的部件。 该提案和实验的目的建议重点关注鞭毛的结构组织 杆和丝，特别是：（i）评估控制鞭毛丝长度的细胞机制和 伸长率，以及 (ii) 定义构成杆的组件并确定其长度和长度的调节 集会。我们将使用遗传、生化和细胞生物学技术来解决拟议的实验。 总的来说，这些目标旨在促进我们对细菌纳米机器调控及其作用的理解 对细胞生理学和健康的贡献。