Isolation and characterization of a lytic bacteriophage (VB_PAnP_PADP4) against MDR- Pseudomonas aeruginosa isolated from septic wound infections

Resistance to multiple drugs by pathogens has become the sweltering problem for the treatment of bacterial infections. To overcome this problem of drug resistance, several diversified bacteriophages can be used as one of the alternatives and attractive approaches. The present study aimed to detect, isolate and partially characterize the bacteriophage used against MDR-Pseudomonas aeruginosa isolated from wound infections. A total number of 130 pus samples were collected and processed for the bacterial isolates from which a potential pathogen (P. aeruginosa) was identified and characterized using morphological, biochemical and molecular techniques (16S r-DNA technique). Among the Pseudomonas isolates, 26 multidrug-resistant strains were detected by Kirby-Bauer disc diffusion method. Bacteriophages (n=15) were collected against the MDR-P. aeruginosa and one of the efficient lytic phage (PADP4) was selected for this study. The transmission electron microscopic studies revealed that the selected phage PADP4 morphological features resemble the Podoviridae family. Phage PADP4 had the highest stability in a broad range of pH, temperatures, and high burst size (270 phages/ infected bacterial cells). Further, the potential phage, PADP4 was co-cultured with MDR-Pseudomonas aeruginosa and showed a significant growth reduction at 12 h of incubation and at multiplicity of infection of 1. Irrespective of the drug resistant bacteria, phage PA DP4 showed perfect lytic activity against the MDR- P. aeruginosa. It has been clarified that PADP4 could be a future promising agent for controlling MDR-P. aeruginosa. Key words: Septic wounds, MDR-P. aeruginosa, bacteriophage, transmission electron microscope (TEM).