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Independent host- and bacterium-based determinants protect a model symbiosis from phage predation.

ABSTRACT: Bacteriophages (phages) are diverse and abundant constituents of microbial communities worldwide, capable of modulating bacterial populations in diverse ways. Here, we describe the phage HNL01, which infects the marine bacterium Vibrio fischeri. We use culture-based approaches to demonstrate that mutations in the exopolysaccharide locus of V. fischeri render this bacterium resistant to infection by HNL01, highlighting the extracellular matrix as a key determinant of HNL01 infection. Additionally, using the natural symbiosis between V. fischeri and the squid Euprymna scolopes, we show that, during colonization, V. fischeri is protected from phages present in the ambient seawater. Taken together, these findings shed light on independent yet synergistic host- and bacterium-based strategies for resisting symbiosis-disrupting phage predation, and we present important implications for understanding these strategies in the context of diverse host-associated microbial ecosystems.

SUBMITTER: Lynch JB

PROVIDER: S-EPMC8983117 | biostudies-literature | 2022 Feb

REPOSITORIES: biostudies-literature

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Independent host- and bacterium-based determinants protect a model symbiosis from phage predation.

Lynch Jonathan B JB Bennett Brittany D BD Merrill Bryan D BD Ruby Edward G EG Hryckowian Andrew J AJ

Cell reports 20220201 7

Bacteriophages (phages) are diverse and abundant constituents of microbial communities worldwide, capable of modulating bacterial populations in diverse ways. Here, we describe the phage HNL01, which infects the marine bacterium Vibrio fischeri. We use culture-based approaches to demonstrate that mutations in the exopolysaccharide locus of V. fischeri render this bacterium resistant to infection by HNL01, highlighting the extracellular matrix as a key determinant of HNL01 infection. Additionally ...[more]

PMID: 35172163

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Independent host- and bacterium-based determinants protect a model symbiosis from phage predation.

Publications

Independent host- and bacterium-based determinants protect a model symbiosis from phage predation.

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