PROKARYOTIC SWARM CELL DIFFERENTIATION & PHOTOPERCEPTION

原核群体细胞分化

• 批准号: 6180869
• 负责人: CARL Eugene BAUER
• 金额: $ 19.74万
• 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/6180869
• 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（改编自申请人摘要）：该提案是 以群体细胞分化的研究为中心 百红螺菌 (Rhodospirillum centenum) 细菌的光感知。 这个品种 与具有单个极鞭毛的细胞类型不同，用于 液体中的运动进入多鞭毛细胞群，该细胞能够 在固体表面上快速移动。 申请人的研究表明 R. Centenum 拥有独特的固体表面感知机制， 随后诱导群细胞分化。 为了研究这个过程， 将表征分化突变体。 运动突变体 致病菌霍乱弧菌、沙门氏菌、空肠弯曲菌和 众所周知，幽门螺杆菌的毒性比野生的要低得多 类型细胞。 奇异变形杆菌的群细胞分化突变体具有 也被证明在感染膀胱或 肾。 这些结果表明，运动性和向群细胞的转化 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际意义 病原微生物侵袭性的影响。 R. Centenum 群细胞集落还表现出卓越的能力 快速向光迁移或远离光迁移。 由于许多突变体获得于 群细胞分化的研究存在光感觉缺陷 感知，这使我们能够从基因角度剖析光的过程 洞察力。 光合微生物能够形成大量的 在光、温度、氧气和水环境中开花 营养物质是最佳的，有几个物种会产生有毒的代谢物 可能对人类和动物造成致命威胁。 光驱动分析 因此，菌落运动对于光感应研究具有广泛的意义 多种运动细菌表现出的运动能力。