Isolation and Characterization of a Lytic Staphylococcus aureus Phage WV against Staphylococcus aureus Biofilm

Abstract

<b><i>Background:</i></b> <i>Staphylococcus aureus</i> is a Gram-positive, pathogenic bacterium that causes a wide range of symptoms in humans and can form biofilm, which is a multicellular community of microorganisms that attaches to nonbiological and biological surfaces. <b><i>Methods:</i></b> Here, we aimed to isolate and characterize an <i>S. aureus</i> phage and examine the bactericidal activity alone and in conjunction with streptomycin treatment. <b><i>Results:</i></b> We isolated a virulent phage, WV, from a slaughterhouse in Jiangsu, China. This strain belonged to the family Myoviridae and presented a genome size of 141,342 bp. The optimal pH of the preservation buffer was 6–7, optimal growth temperature was 37°C, and optimal multiplicity of infection was 0.01. Phage WV can sterilize most clinical strains of <i>S. aureus</i> that had been isolated from clinical patients in the First People’s Hospital of the Yunnan Province. Against low-concentration <i>S. aureus</i> culture, streptomycin demonstrated a greater antibiofilm effect than that of phage WV. By contrast, in high-concentration <i>S. aureus</i> culture, phage WV demonstrated greater antibiofilm effect than that of streptomycin. The use of phage WV and streptomycin together had a substantially greater overall antibiofilm effect than that achieved using either component alone. <b><i>Conclusion:</i></b> This study provides strong evidence for the effectiveness of phage application for the reduction of <i>S. aureus</i> biofilm growth and suggests that phages can be considered as a viable alternative to antibiotics in clinical settings.