Isolation and Genome Sequence Characterization of Bacteriophage vB_SalM_PM10, a Cba120virus, Concurrently Infecting Salmonella enterica Serovars Typhimurium, Typhi, and Enteritidis

The prevalence of multidrug-resistant Salmonella is ever increasing and calls for alternatives to antibiotics. The use of phages has been anticipated to reduce the multidrug-resistant human pathogens in food environment. Salmonella phage vB_SalM_PM10 (PM10) was isolated from sewage-polluted river in India. It shows an icosahedral head (94 +/- 4nm) along with a long contractile tail (106 +/- 7x18 +/- 2nm), a morphotype offamily Ackermannviridae. Additionally, the phage displayed the features resembling to existing Cba120viruses. Phage PM10 could infect S. enterica serovars Typhimurium, Typhi, and Enteritidis. The genome sequencing analysis of phage PM10 revealed circular 158.08kb double-stranded DNA, with the GC content of 44.6%. Two hundred and nine ORFs, 171 putative promoters, 122 rho-independent terminators, and 5 transfer RNA encoding genes were found in the genome. The genome-wide comparisons and phylogenetic analyses showed that phage PM10 is closely related to Salmonella phage PhiSH19. Comparison of the tail-spike protein sequences encoded in PM10 and PhiSH19 genome showed the variation, which might have facilitated PM10's simultaneous infectivity to aforementioned S. enterica serovars. This is a varied host range than that of PhiSH19 or any other Cba120viruses.