INSERM U722 and Université Paris 7 Denis Diderot, Paris 75018, France.
Nat Rev Microbiol. 2010 Mar;8(3):207-17. doi: 10.1038/nrmicro2298.
The primary habitat of Escherichia coli is the vertebrate gut, where it is the predominant aerobic organism, living in symbiosis with its host. Despite the occurrence of recombination events, the population structure is predominantly clonal, allowing the delineation of major phylogenetic groups. The genetic structure of commensal E. coli is shaped by multiple host and environmental factors, and the determinants involved in the virulence of the bacteria may in fact reflect adaptation to commensal habitats. A better characterization of the commensal niche is necessary to understand how a useful commensal can become a harmful pathogen. In this Review we describe the population structure of commensal E. coli, the factors involved in the spread of different strains, how the bacteria can adapt to different niches and how a commensal lifestyle can evolve into a pathogenic one.
大肠杆菌的主要栖息地是脊椎动物的肠道，在那里它是主要的需氧生物，与宿主共生。尽管存在重组事件，但种群结构主要是克隆的，这允许主要的系统发育群体的划定。共生大肠杆菌的遗传结构受到多种宿主和环境因素的影响，而细菌毒力的决定因素实际上可能反映了对共生栖息地的适应。更好地描述共生小生境对于理解有益的共生体如何变成有害的病原体是必要的。在这篇综述中，我们描述了共生大肠杆菌的种群结构、不同菌株传播所涉及的因素、细菌如何适应不同的小生境以及共生生活方式如何演变成致病生活方式。
