Characterization and genomic study of a novel lytic phage of Vibrio parahaemolyticus vB_VpS_BA27

Phages, which specifically infect and lyse bacteria, are of significant value in the prevention and treatment of bacterial infections, as well as in the management of environmental microbiota. Vibrio parahaemolyticus, a prevalent pathogen in aquaculture, causes diseases in aquatic animals and frequently leads to foodborne illnesses in humans. In this study, we isolated a phage specific to V. parahaemolyticus (vB_VpS_BA27) from water samples collected from a diseased snail pond in a Babylonia areolata aquaculture facility on Donghai Island, Zhanjiang. Then we systematically analyzed the biological characteristics and genomic features of vB_VpS_BA27. The results show that vB_VpS_BA27 remained active across a broad pH range (3–11) and exhibited robust survival capabilities in low-temperature conditions (4–37 ℃). It demonstrated significant antibacterial activity with a burst size of 285.67 PFU·cell⁻¹. Genomic sequencing confirms that vB_VpS_BA27 was a lytic phage, with no detected antibiotic resistance or virulence genes. Phylogenetic analysis indicates that within the class Caudoviricetes, vB_VpS_BA27 was closely clustered with members of the genus Delepquintavirus and that, together with other related phages, they formed a new clade within this class. The study demonstrates that vB_VpS_BA27 exhibits the potential in controlling vibriosis in B. areolata, providing a novel approach for the biological control of diseases in B. areolata aquaculture.