Pectobacterium atrosepticum Phage vB_PatP_CB5: A Member of the Proposed Genus ' Phimunavirus '

is a phytopathogen of economic importance as it is the causative agent of potato blackleg and soft rot. Here we describe the phage vB_PatP_CB5 (abbreviated as CB5), which specifically infects the bacterium. The bacteriophage is characterized in detail and TEM micrographs indicate that it belongs to the family CB5 shares significant pairwise nucleotide identity (≥80%) with phages φM1, Peat1, and PP90 and also shares common genome organization. Phylograms constructed using conserved proteins and whole-genome comparison-based amino acid sequences show that these phages form a distinct clade within the . They also possess conserved RNA polymerase recognition and specificity loop sequences. Their lysis cassette resembles that of , containing in sequential order a U-spanin, a holin, and a signal⁻arrest⁻release (SAR) endolysin. However, they share low pairwise nucleotide identity with the type phage of the genus, phage KP34. In addition, phage KP34 does not possess several conserved proteins associated with these phages. As such, we propose the allocation of phages CB5, Peat1, φM1, and PP90 to a separate new genus designated .