一个单一的调节基因足以改变细菌宿主范围
Mark J Mandel1, Michael S Wollenberg, Eric V Stabb
1Department of Medical Microbiology and Immunology, University of Wisconsin School of Medicine and Public Health, 1550 Linden Drive, Madison, Wisconsin 53706, USA. mmandel@wisc.edu
Nature
|February 3, 2009
概括
一个单一的基因,RscS,使Vibrio fischeri细菌能够殖民鱼. 这种调节基因控制生物膜的形成,对细菌共生和宿主特异性进化至关重要.
科学领域:
- 微生物学 微生物学
- 这种共生是共生.
- 进化生物学 进化生物学
背景情况:
- 微生物共生对动物发育至关重要,但宿主特异性机制尚不清楚.
- 细菌每一代都必须从环境中获得特定的共生伙伴.
- 确定控制细菌宿主特异性的遗传因素是一个关键挑战.
研究的目的:
- 为了研究Vibrio fischeri-Euprymna scolopes鱼共生中的宿主特异性的遗传基础.
- 为了确定负责由Vibrio fischeri.有效殖民鱼的特定基因.
- 了解调节基因在细菌宿主范围进化的作用.
主要方法:
- 进行比较基因组学以识别鱼共生体中存在的,但在鱼共生体中不存在的基因.
- 基因操纵 (异质表达) 用于测试基因功能.
- 遗传学分析,以追踪已识别的基因的进化历史.
- 显微镜和分子技术用于研究生物膜形成和殖民.
主要成果:
- 两组分传感器酶RscS对于维布里奥·菲舍里菌对Euprymna scolopes鱼的殖民是必不可少的,而且足够的.
- RscS诱导Syp外聚糖,这是生物膜介质,对最初的鱼殖民至关重要.
- rscS基因存在于鱼共生体中,但不在鱼类共生体中,例如Vibrio fischeri MJ11.
- 在菌株MJ11中RscS的异质表达使E. scolopes的殖民成为可能,类似于天然鱼共生体.
- 遗传学分析表明rscS在鱼共生进化的过程中发挥了重要作用.
结论:
- 一个单一的调节基因,RscS,可以确定动物相关细菌的宿主范围.
- 通过生物膜形成,RscS通过激活先前存在的细菌能力来促进鱼殖民.
- 这一发现强调了调节基因,而不是直接与宿主相互作用的因子,如何驱动细菌宿主特异性的进化.
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