Strain-level epidemiology is a key approach to understanding the mechanisms underlying establishment of any host-microbe association. The squid-vibrio light organ symbiosis has proven to be an informative and tractable experimental model in which to discover these mechanisms because it involves only one bacterial species, Vibrio fischeri. In this horizontally transmitted symbiosis, the squid presents nutrients to the bacteria located in a bilobed light-emitting organ, while the symbionts provide bioluminescence to their host. To initiate this association, V. fischeri cells go through several distinct stages: from free-living in the bacterioplankton, to forming a multicellular aggregation near pores on the light organ's surface, to migrating through the pores and into crypts deep in the light organ, where the symbiont population grows and luminesces. Because individual cells must successfully navigate these distinct regions, phenotypic differences between strains will have a strong impact on the composition of the population finally colonizing the squid. Here we review recent advances in our understanding of behavioral characteristics that differentially drive a strain's success, including its effectiveness of aggregation, the rapidity with which it reaches the deep crypts, and its deployment of type VI secretion.

中文翻译：

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费氏弧菌菌株变异对宿主定植的影响。

菌株级流行病学是了解建立任何宿主-微生物关联基础机制的关键方法。鱿鱼-弧菌轻器官共生已被证明是一种信息丰富且易于处理的实验模型，其中发现了这些机制，因为它仅涉及一种细菌，即费氏弧菌。在这种水平传播的共生中，鱿鱼向位于双叶发光器官中的细菌提供营养，而共生体为其宿主提供生物发光。为了启动这种联系，费氏弧菌细胞经历几个不同的阶段：从自由生活在浮游细菌中，到在轻器官表面的孔附近形成多细胞聚集，再通过孔隙迁移并进入轻器官深处的隐窝，共生种群生长和发光的地方。因为单个细胞必须成功地在这些不同的区域中导航，所以菌株之间的表型差异将对最终定居在鱿鱼中的种群组成产生重大影响。在这里，我们回顾了对行为特征的理解的最新进展，这些行为以不同的方式驱动菌株的成功，包括其聚集的有效性，到达深层隐窝的速度以及其VI型分泌的部署。