Characterization of the novel temperate Staphylococcus haemolyticus phage IME1365_01

The presence of a novel functional prophage, IME1365_01, was predicted from bacterial high-throughput sequencing data and then successfully induced from Staphylococcus haemolyticus by mitomycin C treatment. Transmission electron microscopy showed that phage IME1365_01 has an icosahedral head (43 nm in diameter) and a long tail (172 nm long). This phage possesses a double-stranded DNA genome of 44,875 bp with a G+C content of 35.35%. A total of 63 putative open reading frames (ORFs) were identified in its genome. BLASTn analysis revealed that IME1365_01 is similar to Staphylococcus phage vB_SepS_E72, but with a genome homology coverage of only 26%. The phage genome does not have fixed termini. In ORF24 of phage IME1365_01, a conserved Toll-interleukin-1 receptor domain of the TIR_2 superfamily (accession no. c123749) is located at its N-terminus, and this might serve as a component of an anti-bacterial system. In conclusion, we developed a platform to obtain active temperate phage from prediction, identification, and induction from its bacterial host. After mass screening using this platform, numerous temperate phages and their innate anti-bacterial elements can provide extensive opportunities for therapy against bacterial (especially drug-resistant bacterial) infections.