Mechanism of Caulobacter adhesion

柄杆菌粘附机制

• 批准号: 7212666
• 负责人: YVES V BRUN
• 金额: $ 31.2万
• 依托单位: TRUSTEES OF INDIANA UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2007
• 资助国家: 美国
• 起止时间: 2007-02-01 至 2011-01-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7212666
• 关键词: Adhesions; Adhesives; Anabolism; Bacteria; Bacterial Adhesins; Bacterial Adhesion; Biochemical; Biological; Biological Models; Biophysics; Caulobacter; Caulobacter crescentus; Cell Cycle; Cell Cycle Regulation; Cell surface; Cells; Complex; Coupled; Disease; Environment; Fiber; Filament; Flagella; Fluorescence Microscopy; Future; Genes; Genetic Screening; Goals; Immunoblot Analysis; Immunofluorescence Microscopy; Individual; Industry; Lasers; Life Cycle Stages; Localized; Measures; Membrane; Methods; Microbial Biofilms; Micromanipulation; Microscopy; Modeling; Pathogenesis; Pilum; Play; Polysaccharides; Process; Protein Biosynthesis; Protein Export Pathway; Protein Tyrosine Kinase; Proteins; Proteolysis; Regulation; Research; Research Personnel; Role; Secretin; Staging; Structure; Surface; System; Tertiary Protein Structure; Testing; Time; Upper arm; Virulence Factors; adhesion process; cell motility; gene function; improved; insight; intracellular protein transport; mutant; pathogen; pathogenic bacteria; protein function; protein localization location; research study; theories

DESCRIPTION (provided by applicant): The adhesion of bacteria to surfaces plays an important role in disease, providing the critical first step in the biofouling of a surface and in biofilm formation. The general goal of this research is to reach a detailed understanding of the mechanisms of bacterial adhesion, from the biophysics of adhesion to the coordination of the biosynthesis of cell surface structures that participate in this process. This project takes advantage of the bacterium Caulobacter crescentus, in which adhesive structures are synthesized in an ordered fashion at the same pole of the cell, making the study of adhesion more amenable than in most bacteria. Initial stages of adhesion involve flagellar motility and pili, and adhesion is cemented by synthesis of a polysaccharide holdfast. Pathogenic bacteria also use these adhesive structures, but their mechanism of action in adhesion is poorly understood. In addition, the adhesive force of individual Caulobacter cells is the strongest ever measured for a biological adhesive. This project has three major aims. The first aim will use highly synchronized cultures coupled to atomic force microscopy, fluorescence microscopy, and biophysical modeling to develop a detailed understanding of the various stages of adhesion. In particular, this aim will investigate a newly discovered surface contact-dependent trigger of adhesive polysaccharide export; this mechanism may also be used by pathogens. The second aim is to determine the function of holdfast polysaccharide synthesis and attachment proteins. Experiments are described to determine the biochemical function of these proteins and their contribution to adhesion. The third aim is to elucidate the mechanisms that control the timing and polar localization of holdfast synthesis. The effect of constitutively expressing holdfast synthesis proteins during the cell cycle on the timing of holdfast synthesis and adhesion will be determined. The localization of holdfast synthesis and attachment proteins and their interdependence for localization will be studied, and factors required for their localization will be identified. Bacterial adhesion, polysaccharide biosynthesis, and subcellular localization of proteins and virulence factors are essential components of bacterial pathogenesis. Insight gained from the study of this simple model system will be applicable to more complex bacterial pathogens and will enhance our ability to inhibit them.

描述（由申请人提供）：细菌对表面的粘附在疾病中起着重要作用，在表面和生物膜形成中提供了关键的第一步。这项研究的一般目标是详细了解细菌粘附机制，从粘附的生物物理学到参与此过程的细胞表面结构的生物合成的协调。该项目充分利用细菌的小核细菌齿状细菌，其中粘合剂结构在细胞的同一极点以有序的方式合成，这使得对粘附的研究比大多数细菌中的粘附性更高。粘附的初始阶段涉及鞭毛运动和pili，并且通过合成多糖固定固定固定而粘附。致病细菌也使用这些粘附结构，但是它们在粘附中的作用机理知之甚少。另外，单个花椰菜细胞的粘合力是有史以来最强的生物粘合剂。该项目具有三个主要目标。第一个目的将使用与原子力显微镜，荧光显微镜和生物物理建模相连的高度同步培养物，以详细了解粘附的各个阶段。特别是，该目标将研究新发现的粘性多糖导出的表面接触依赖性触发。病原体也可以使用这种机制。第二个目的是确定Holdfast多糖合成和附着蛋白的功能。描述了实验以确定这些蛋白质的生化功能及其对粘附的贡献。第三个目的是阐明控制持有的时间和极性合成的定位的机制。在细胞周期中，组成型表达持有的合成蛋白对持有的固定合成和粘附时间​​的影响。将研究Holdfast合成和附着蛋白的定位及其在本地化的相互依赖性，将确定其定位所需的因素。细菌粘附，多糖生物合成和蛋白质的亚细胞定位和毒力因子是细菌发病机理的必要组成部分。从对这个简单模型系统的研究中获得的洞察力将适用于更复杂的细菌病原体，并增强我们抑制它们的能力。