Bacteriostatic Activity of <i>Vibrio parahaemolyticus</i> Phage 460s1 and Its Endolysin

<i>Vibrio parahaemolyticus</i> is a common foodborne pathogen with drug-resistant strains now widespread. The use of phages to control resistant bacteria is a promising means of reducing public health pressure. In this study, <i>V. parahaemolyticus</i> phage 460s1 was isolated, which was active over a wide range of temperature (30-50°C) and pH (3-10). It exhibited a specific host range, lysing 16 of the 23 strains of <i>V. parahaemolyticus</i>. The phage 460s1 can effectively inhibit the growth of <i>V. parahaemolyticus</i> in shrimp at 15°C and 25°C, and bacterial count decreased by 3.46 log colony-forming unit/g at multiplicity of infection of 1000 at 24 h under 15°C. The phage 460s1 genome was sequenced, and it contains 105 open reading frames (ORFs), of which ORF 53 encodes putative endolysin. The ORF 53 protein was successfully expressed in <i>Escherichia coli</i> and reduced the optical density at 600 nm of host bacteria from 0.82 to 0.58 within 60 min at a concentration of 10 μmol/L. The endolysin also showed lytic activity against 20 strains of antimicrobial-resistant <i>V. parahaemolyticus</i>. Therefore, bacteriophage 460s1 and its endolysin are of great significance for the prevention and control of <i>V. parahaemolyticus</i>.