isolation, characterization, and antibacterial activity of lytic bacteriophage against methicillin-resistant staphylococcus aureus causing bedsore and diabetic wounds

Background and objectives: phage therapy has gained interest as an alternative treatment for methicillin-resistant staphylococcus aureus (mrsa) infections. the purpose of this study was to isolate and characterize an effective bacteriophage against isolates of mrsa. materials and methods: bacteriophage was isolated from hospital sewage. lytic activity and the titers of phage lysates were measured using spot test and double-layer plaque assay. the phage characterization was determined through transmission electron microscopy. adsorption rate, host range and stability tests were investigated. the latent period and burst size were estimated from a one-step growth curve. the effect of bacteriophage against mrsa biofilms was determined and real-time pcr was used to assess the effects of the bacteriophage on the expression of the biofilm-associated genes. results: tem results showed that the phage resembled the cystoviridae family. its latent period was 30 min, corresponding to about 71/43 phage particles per infected cell. the phage had a broad host range and it was most stable at 37°c and ph 7. it was sensitive to nacl concentrations. the expressions of the biofilm-associated genes were significantly reduced in the presence of the phage. conclusion: the isolated phage was effective against mrsa strains and it can be an optional strategy of controlling biofilm development.