PROKARYOTIC SWARM CELL DIFFERENTIATION & PHOTOPERCEPTION

原核群体细胞分化

• 批准号: 2681474
• 负责人: CARL Eugene BAUER
• 金额: $ 18.69万
• 依托单位: TRUSTEES OF INDIANA UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 1998
• 资助国家: 美国
• 起止时间: 1998-08-01 至 2002-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/2681474
• 关键词: Halobacteriaceae; Rhodospirillum; cell differentiation; chemotaxis; cilium /flagellum motility; nonvisual photoreceptor; nonvisual photosensitivity; nucleic acid sequence; polymerase chain reaction; virulence

DESCRIPTION (Adapted from the applicants abstract): This proposal is centered on an investigation of swarm cell differentiation and photoperception by the bacterium Rhodospirillum centenum. This species differentiates from a cell type that has a single polar flagellum used for motility in liquids into a multiflagellated swarm cell which is capable of rapid motility on solid surfaces. The applicant's studies have demonstrated that R. Centenum has a unique mechanism of solid surface perception and subsequent induction of swarm cell differentiation. To study this process, differentiation mutants will be characterized. Motility mutants of the pathogenic bacteria Vibrio cholerae, Salmonella, Campylogbacter jejuni and Helicobacter pylori are know to be significantly less virulent than wild type cells. Swarm cell differentiation mutants of Proteus mirabilis have also been shown to be defective in their ability to infect the bladder or kidney. These results indicate that motility and conversion to swarm cells is an important virulence determinant for some pathogens. Information obtained from this study could therefore have significant practical implications regarding the invasiveness of pathogenic microorganisms. R. Centenum swarm cell colonies also exhibit the remarkable ability to rapidly migrate toward or away from light. Since many mutants obtained in the study of swarm cell differentiation are defective in photosensory perception, this allows us to genetically dissect the process of light perception. Photosynthetic microorganisms are capable of forming massive blooms in aqueous environments where light, temperature, oxygenicity and nutrients are optimal, with several species producing toxic metabolites that can cause deadly threats to humans and animals. Analysis of light-driven colony motility thus has broad implications for the study of photosensory motility exhibited by a variety of motile bacteria.

描述(改编自申请者摘要)：本建议书 以研究群体细胞分化和 红螺菌对光的截获作用。这一物种 区别于具有单个极生鞭毛的细胞类型 在液体中移动到一个多鞭毛的群体细胞，它能够 在固体表面上快速运动。申请者的研究表明 百里香具有独特的固体表面感知机制， 随后诱导群体细胞分化。为了研究这一过程， 将对差异化突变体进行表征。的运动性突变体 致病菌霍乱弧菌、沙门氏菌、空肠弯曲杆菌和 已知幽门螺杆菌的毒力比野生幽门螺杆菌小得多 键入单元格。奇异变形杆菌群体细胞分化突变体 也被证明在感染膀胱部或 肾脏。这些结果表明，向群体细胞的运动性和转化 是某些病原体的重要毒力决定因素。信息 因此，从这项研究中获得的结果可能具有重要的实用价值 关于病原微生物侵袭性的影响。 百里香菌群细胞克隆也表现出显著的能力 迅速地向光迁移或远离光。因为许多突变体在 群体细胞分化的研究在光感方面存在缺陷 感知，这使我们能够从基因上剖析光的过程 感知力。光合作用的微生物能够形成大量 在水环境中开花，光、温度、含氧量和 营养素是最佳的，有几种物种会产生有毒的代谢物， 会对人类和动物造成致命威胁。关于光驱动的分析 因此，菌落运动对光感受器的研究具有广泛的意义。 各种可移动细菌所表现出的能动性。