Vibrio fischeri bacteriophage sequencing and assembly

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