Scan to discover onlineBackground & Objective: This study aims to isolate a lytic bacteriophage against planktonic Enterococcus faecalis V583 culture and evaluate its ability to disrupt and inhibit biofilm.Methods: An anti-E. faecalis phage was isolated from sewage and visualized by electron microscopy, the vB_EfsS_V583 (V583) host range was determined by spot test on 13 E. faecalis clinical strains .Inhibition and degradation experiments were designed to investigate the effect of phage on biofilm. In the inhibition and degradation assay, biofilms were formed in the presence and absence of phage, respectively . Finally, crystal violet method tested the effect of phage on biofilm.Results: Phage V583 belongs to the Siphoviridae family and can infect all E. faecalis strains. Antibacterial activity has been shown to degrade and inhibit biofilm produced by V583. The study results showed that phage v583 is more efficient in biofilm inhibition than biofilm degradation. In both assays, phage-treated wells' absorption is less than untreated wells. These results were confirmed by Colony-forming unit reduction in the treated biofilm. Conclusion:The anti-biofilm activity showed that phage therapy using phage V583 might be an alternative tool to remove E. faecalis biofilms.

Background and Objectives: An important leading cause of the emergence of vancomycin-resistant enterococci, especially Enterococcus faecium, is the inefficiency of antibiotics in the elimination of drug-resistant pathogens. Consequently, the need for alternative treatments is more necessary than ever. Materials and Methods: A highly effective bacteriophage against vancomycin-resistant E. faecium called vB-EfmS-S2 was isolated from hospital sewage. The biological properties of phage S2 and its effect on biofilm structures were determined. Results: Phage S2 was specifically capable of lysing a wide range of clinical E. faecium isolates. According to Electron mi- croscopy observations, the phage S2 belonged to the Siphoviridea family. Suitable pH spectra for phage survival was 5-11, at which the phage showed 100% activity. The optimal temperature for phage growth was 30-45°C, with the highest growth at 37°C. Based on one-step growth curve results, the latent period of phage S2 was 14 min with a burst size of 200 PFU/ml. The phage S2 was also able to tolerate bile at concentrations of 1 and 2% and required Mg2+ for an effective infection cycle. Biofilms were significantly inhibited and disrupted in the presence of the phage. Conclusion: According to the results, phage S2 could potentially be an alternative for the elimination and control of vancomycin-resistant E. faecium biofilm.