New virulent bacteriophages active against multiresistant Pseudomonas aeruginosa strains

The sensitivity of 512 newly isolated Pseudomonas aeruginosa clinical strains to six classes of antimicrobial preparations has been studied. Antibiotic-resistant strains were selected and genotyped. Three new virulent bacteriophages of the families Myoviridae and Podoviridae were isolated against these strains. The parameters of the intracellular phage development cycle were established, and the influence of inactivating factors (temperature, pH, and UV exposure) on phage viability was studied. The molecular weight of the phage genome was determined. Phage DNA restriction analysis and structural protein composition analysis by SDS polyacrylamide gel electrophoresis were carried out. The plating efficacy of phages on 28 genetically distant antibiotic-resistant P. aeruginosa strains was studied. It was established that 26 of them were lysed by phages with a high efficacy. The range of antibacterial action of the studied phages and their mixtures on 427 multidrug-resistant clinical isolates was assessed. It is shown that including these phages in one multicomponent preparation enhanced their lytic activity.