Isolation and characterization of Pseudomonas aeruginosa bacteriophages — potential agents for phage therapy

Abstract

Pseudomonas aeruginosa — is one of the pathogens characterized by the critical number of multidrug-resistant (MDR) strains. Phage therapy is considered an alternative to antibiotics, especially in treatment of infections caused by MDR strains. The aim of this study was to isolate and characterize P. aeruginosa phages that could potentially be suitable for treating infectious diseases. To isolate the P. aeruginosa phages, enrichment cultures were used. The lytic activity spectrum was confirmed by spot testing on 40 P. aeruginosa strains. Whole-genome sequencing was performed using Illumina MiSeq instrument. Phylogenetic analysis was done using VICTOR tool. Isolated phages vB_PaeA-55-1w and vB_PaeM-198 from Autographiviridae and Myoviridae families, respectively, had a broad spectrum of lytic activity (about 50% each), including lysis of MDR strains. The genomes vB_PaeA-55-1w and vB_PaeM-198 comprise double-stranded DNA of 42.5 and 66.3 kbp in length, respectively. Open reading frames were annotated for both phages (52 for vB_PaeA-55-1w, and 95 for vB_PaeM-198), no integrases and toxins were detected. On a phylogenetic tree, vB_PaeA-55-1w phage was clustered with phages from the Phikmvvirus genus (Autographiviridae family), which are also used in phage therapy. vB_PaeM-198 phage was clustered with phages from the Pbunavirus genus (Myoviridae family). vB_PaeA-55-1w and vB_PaeM-198 phages could be considered as candidates for phage therapy and may be used to treat infections caused by MDR P. aeruginosa.