Characterization of novel of temperate phages of Staphylococcus aureus isolated from bovine milk.

Bovine mastitis is an important disease in dairy cows, and Staphylococcus aureus is the most prevalent microorganism. Bacteriophages are considered an alternative to treat bacterial infections due to antimicrobial resistance crisis. In this study, we isolated and characterized novel S. aureus temperate phages, namely B_UFSM4 and B_UFSM5, from bovine milk. The complete genomes of B_UFSM4 and B_UFSM5 have 41.396 bp and 41.829 bp, respectively. The viruses have double-stranded DNA and linear architecture. Phylogenic similarity was observed by proteome with Staphylococcus phage phiPV83, CN125 and JS01. Therefore, the phages were classified into the family Siphoviridae, genus Biseptimavirus and order Caudovirales. In the host range, the B_UFSM4 and B_UFSM5 had lytic activity of 45.8% and 54.16%, respectively, inclusive on isolates from Staphylococcus sciuri and Rothia terrae. Thus, in this study, species novel of S. aureus temperate phages was isolated and characterized, these phages reveal similarities to each other; however, they are distinct from other species of S. aureus phages of the family Siphoviridae.