https://dx.doi.org/10.7554/eLife.24414">
 

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Creative Commons Attribution 4.0 License
This work is licensed under a Creative Commons Attribution 4.0 License.

Abstract

Host immune and physical barriers protect against pathogens but also impede the establishment of essential symbiotic partnerships. To reveal mechanisms by which beneficial organisms adapt to circumvent host defenses, we experimentally evolved ecologically distinct bioluminescent Vibrio fischeri by colonization and growth within the light organs of the squid Euprymna scolopes. Serial squid passaging of bacteria produced eight distinct mutations in the binK sensor kinase gene, which conferred an exceptional selective advantage that could be demonstrated through both empirical and theoretical analysis. Squid-adaptive binK alleles promoted colonization and immune evasion that were mediated by cell-associated matrices including symbiotic polysaccharide (Syp) and cellulose. binK variation also altered quorum sensing, raising the threshold for luminescence induction. Preexisting coordinated regulation of symbiosis traits by BinK presented an efficient solution where altered BinK function was the key to unlock multiple colonization barriers. These results identify a genetic basis for microbial adaptability and underscore the importance of hosts as selective agents that shape emergent symbiont populations.

Publication Date

4-27-2017

Journal Title

eLIFE

Publisher

eLife Sciences Publications

Digital Object Identifier (DOI)

https://dx.doi.org/10.7554/eLife.24414

Scientific Contribution Number

2666

Document Type

Article

Rights

eLIFE© 2017, Sabrina Pankey et al.

Comments

This is an article published by eLife Sciences Publications in eLife in 2017, available online: https://dx.doi.org/10.7554/eLife.24414

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