Comparison of the genomes of Vibrio phages pVco-5 and pVco-7: implications for phage-host interactions.

Oyster hatcheries suffer significant mortality caused by members of the bacterial genus Vibrio, which infect Crassostrea gigas larvae. Bacteriophages present a potential alternative to antibiotics, with N4-like phages showing promise against vibriosis. We investigated the adsorption properties and determined the complete genome sequence of phage pVco-7 and performed phylogenetic and comparative analysis with other N4-like Vibrio phages to gain insights into phage resistance mechanisms and infection strategies. The phage has a linear dsDNA genome with 126 genes and a typical N4-like organization. Tail fiber variations were identified that could potentially influence host recognition, providing insights into how phages of the genus Vicoquintavirus interact with their host as well as their evolutionary relationships. These findings will contribute to the development effective biocontrol strategies against vibriosis in commercially important bivalve aquaculture.