Establishment of an animal-bacterial association: Recruiting symbiotic vibrios from the environment
Establishment of an animal-bacterial association: Recruiting symbiotic vibrios from the environment
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DOI：
10.1073/pnas.97.18.10231
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发表时间：
2000-08-29
影响因子：
11.1
通讯作者：
McFall-Ngai, MJ
中科院分区：
文献类型：
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作者：
Nyholm, SV;Stabb, EV;McFall-Ngai, MJ
虽然大多数动物-细菌共生关系每一代都被重新建立，但宿主及其潜在微生物伙伴确保组织定植的机制在很大程度上仍未被描述。我们使用鱿鱼Euprymna scopes和费氏弧菌（Vibrio fischeri）之间的模型关联来研究这一过程。当周围海水中的V. fischeri细胞进入新生器官表面的孔隙并定植在上皮层的深层隐窝时，这种轻器官共生就开始了。我们发现，当新孵化的鱿鱼实验暴露在天然海水中时，动物的反应是分泌一种粘性物质从器官的孔隙中。被重新引入。这种粘性物质只结合对n -乙酰神经氨酸或n -乙酰半乳糖胺具有特异性的凝集素，这表明它是由含有黏液的基质组成的。器官表面复杂的纤毛场产生水流，将基质聚集成一个团块，这个团块被系住并悬浮在光器官的孔上。当将费氏弧菌细胞引入鱿鱼周围的海水中时，细菌在通风时被吸入充满液体的体腔，并在基质中被捕获。在聚集几个小时后，共生体迁移到孔中并在隐窝上皮中定植。这种感染模式可能是水生宿主增加很少遇到的共生体成功定植可能性的广泛策略的一个例子。
While most animal-bacterial symbioses are reestablished each successive generation, the mechanisms by which the host and its potential microbial partners ensure tissue colonization remain largely undescribed. We used the model association between the squid Euprymna scolopes and Vibrio fischeri to examine this process. This light organ symbiosis is initiated when V. fischeri cells present in the surrounding seawater enter pores on the surface of the nascent organ and colonize deep epithelia-lined crypts, We discovered that when newly hatched squid were experimentally exposed to natural seawater, the animals responded by secreting a viscous material from the pores of the organ, Animals maintained in filtered seawater produced no secretions unless Gram-negative bacteria, either living or dead, were reintroduced. The viscous material bound only lectins that are specific for either N-acetyl-neuraminic acid or N-acetylgalactosamine, suggesting that it was composed of a mucus-containing matrix. Complex ciliated fields on the surface of the organ produced water currents that focused the matrix into a mass that was tethered to, and suspended above, the light organ pores, When V. fischeri cells were introduced into the seawater surrounding the squid, the bacteria were drawn into its fluid-filled body cavity during ventilation and were ca ptu red in the matrix. After residing as an aggregate for several hours, the symbionts migrated into the pores and colonized the crypt epithelia, This mode of infection may be an example of a widespread strategy by which aquatic hosts increase the likelihood of successful colonization by rarely encountered symbionts.