Phage vB_BtS_B83 Previously Designated as a Plasmid May Represent a New Genus.

The group of bacteria includes, inter alia, the species known to be associated with human diseases and food poisoning. Here, we describe the phage vB_BtS_B83 (abbreviated as B83) infecting the species of this group. Transmission electron microscopy (TEM) micrographs indicate that B83 belongs to the family. B83 is a temperate phage using an arbitrium system for the regulation of the lysis-lysogeny switch, and is probably capable of forming a circular plasmid prophage. Comparative analysis shows that it has been previously sequenced, but was mistaken for a plasmid. B83 shares common genome organization and >46% of proteins with other the phage, BMBtp14. Phylograms constructed using large terminase subunits and a pan-genome presence-absence matrix show that these phages form a clade distinct from the closest viruses. Based on the above, we propose the creation of a new genus named that includes B83 and BMBtp14.