The regulation of Pseudomonas aeruginosa surface colonization

描述(申请人提供)：在囊性纤维化(CF)患者中，肺部慢性定植铜绿假单胞菌导致频繁住院和过早死亡。铜绿假单胞菌可以通过多种方式在表面定植：集群运动、滑动运动和生物膜的形成。细菌表面成分(如IV型菌毛、胞外多糖、鞭毛和鼠李糖脂)的表达对这些活动很重要，但目前对这些因素的相互作用和共同调节的了解还不完全。默里博士有初步证据表明，铜绿假单胞菌产生的某些调节蛋白各自控制着对定植至关重要的多个因素。他的研究目标是：1)确定由这些蛋白共同调节的表面定植所需的成分(使用不同程度缺乏这些调节蛋白的铜绿假单胞菌菌株，并在集群、滑动和生物膜形成期间测量菌毛、鞭毛蛋白、胞外多糖和鼠李糖脂的水平)；2)在感染的CF组织培养模型中量化这些菌株对表面的定植(通过共聚焦显微镜观察细菌/上皮细胞的相互作用，并用Comstat软件分析这些图像)；3)体外表面定植缺陷与体内异常慢性定植的相关性(通过检测感染这些菌株的大鼠的细菌恢复、组织学和肺内免疫反应)。了解这些过程可能会导致新的治疗方法。默里博士将通过学习新技术来补充他在微生物学方面的经验：实时聚合酶链式反应、共聚焦显微镜、CF组织培养模型和慢性肺炎的大鼠模型。默里博士的主要导师在动物感染模型方面拥有专业知识，他的咨询委员会包括微生物发病机制方面的专家和耶鲁大学CF中心的主任，后者将教他这些技能。他将参加翻译研究、免疫生物学和动物护理方面的课程。通过这次额外的培训，默里博士将获得成为假单胞菌慢性感染发病机制的独立调查员的工具。相关性(见说明)：铜绿假单胞菌多年来生活在囊性纤维症患者的肺部，导致频繁住院。目前的抗生素疗法在消除细菌方面并不成功，需要新的治疗方法。该项目的目标是更好地了解铜绿假单胞菌的特性，使其能够在肺部存活，从而可能开发新的治疗方法。

DESCRIPTION (provided by applicant): In patients with cystic fibrosis (CF), chronic colonization of the lungs with Pseudomonas aeruginosa results in frequent hospitalizations and in premature mortality. P. aeruginosa can colonize surfaces in multiple ways: swarming motility, sliding motility and the formation of biofilms. Expression of components on the surface of the bacteria (e.g. type IV pili, exopolysaccharide, flagella, and rhamnolipids) is important for these activities, but current understanding of the interactions and co-regulation of these factors is incomplete. Dr. Murray has preliminary evidence that certain regulatory proteins produced by P. aeruginosa each controls multiple factors important for colonization. His research goals are to: 1) Determine the components required for surface colonization co-regulated by these proteins (using strains of P. aeruginosa that variously lack these regulatory proteins and measuring levels of pilin, flagellin, exopolysaccharide, and rhamnolipid during swarming, sliding and formation of biofilms); 2) To quantitate the colonization of surfaces by these strains in a CF tissue culture model of infection (by visualizing bacterial/epithelial cell interactions with confocal microscopy and analyzing these images with COMSTAT software); and 3) To correlate in vitro surface colonization defects with abnormal chronic colonization in vivo (by measuring the recovery of bacteria, histology, and the immune response in the lungs of rats infected with these strains). Understanding these processes may lead to novel therapies. Dr. Murray will complement his experience in microbiology by learning new techniques: real time PCR, confocal microscopy, a CF tissue culture model, and a rat model of chronic pneumonia. Dr Murray's primary mentor has expertise in animal infection models and his advisory committee includes experts in microbial pathogenesis and the director of Yale's CF Center who will teach him these skills. He will take courses in translational research, immunobiology, and animal care. Through this additional training, Dr. Murray will gain the tools to become an independent investigator in the pathogenesis of chronic infection by Pseudomonas. RELEVANCE (See instructions): The bacterium Pseudomonas aeruginosa lives in the lungs of people with cystic fibrosis for many years, resulting in frequent hospitalizations. Current antibiotic therapies are not successful in eliminating the bacteria and new approaches to therapy are needed. The goal of this project is to better understand the properties of P. aeruginosa that allow it to survive in the lung so new therapies may be developed.