Isolation and characterization of a novel bacteriophage against Vibrio alginolyticus from coastal waters and its environmental tolerance

In response to the problems associated with drug resistance resulting from the use of antibiotics, phages have become desirable options for the treatment of Vibrio alginolyticus disease in aquaculture. In this study, we isolated a novel double-stranded DNA (dsDNA) phage named vB_ValC_WD615 infecting V. alginolyticus; this phage belongs to the family Podoviridae and has a short noncontractile tail (13 ± 1.5 nm) and an icosahedral head (60.2 ± 2 nm); its genome is 50,522 bp and encodes 69 open reading frames (ORFs) and no lysogenic genes were annotated in the genome. Physiological results indicate that vB_ValC_WD615 infects V. alginolyticus SC1 with a burst size of 335 PFU/cell and can maintain stable infectivity within temperature and pH conditions ranging from 4 to 45 °C and 3 to 11, respectively. The results suggest that the vB_ValC_WD615 isolated from coastal waters could be a potential candidate for phage therapy targeting V. alginolyticus.