Description and host-range determination of phage PseuPha1, a new species of Pakpunavirus infecting multidrug-resistant clinical strains of Pseudomonas aeruginosa

A new phage PseuPha1, infecting multiple multi-drug resistant strains of Pseudomonas aeruginosa with strong anti-biofilm activities, was isolated from wastewater in India. PseuPha1 showed optimal multiplicity of infection at 10-3, maintained the infectivity at wide ranges of pH (6-9) and temperature (4-37 0C), and exhibited 50 minutes latent period and a burst size of 200 when tested against P. aeruginosa PAO1. PseuPha1 shared 86.1-89.5% pairwise intergenomic similarity with Pakpunavirus species (n = 11) listed by the International Committee on Taxonomy of Viruses and established distinct phyletic lineages during phylogenetic analyses of phage proteins. While genomic data validated the taxonomic novelty and lytic attributes of PseuPha1, BOX-PCR profiling asserted the genetic heterogeneity of susceptible clinical P. aeruginosa. Our data supported the affili-ation of PseuPha1 as a new Pakpunavirus species and provided the first line of evidence for its virulence and infectivity that can be harnessed in wound therapeutics.