A bacteriophage JN02 infecting multidrug‐resistant Shiga toxin‐producing Escherichia coli : isolation, characterisation and application as a biocontrol agent in foods

Bacteriophages are increasingly considered as novel biocontrol agents against Multidrug‐resistant (MDR) Shiga toxin‐producing Escherichia coli (STEC). In this study, a virulent phage JN02 capable of infecting MDR STEC was isolated, characterised and evaluating its efficacy in reducing MDR STEC in foods. One‐step growth and stability assay showed that JN02 had a relatively short latent period (15 min), large burst sizes (69 PFU/cell), and high physicochemical stability (temperature (30–60°C), pH (2–11), 0.1%, 1% pig bile salt, biocides and food additives (100% chloroform, 0.1% acetic acid, 1% potassium sorbate). In spot tests, 18 E. coli strains were sensitive to JN02. In efficiency of plating (EOP), 4 E. coli strains were sensitive to JN02. Electron microscopy and genome sequencing showed that JN02 belongs to the family Myoviridae . Importantly, no known virulence‐associated, lysogenic and antibiotic genes were identified in the genome of JN02. Viable cell counts of MDR STEC were significantly ( P <  0.05) reduced in milk (no viable counts) and beef samples (1.0–1.9 log 10 CFU cm −2 reduction) when treated with JN02 at 4 °C. The results indicated that JN02 might be a new potential natural biological control agent for MDR STEC in foods.