Biological characteristics and anti-biofilm activity of a lytic phage against vancomycin-resistant Enterococcus faecium

Abstract

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.

Anti-biofilm Activity of a Lytic Phage Against Vancomycin-Resistant Enterococcus faecalis

“…Isolation of phage was performed using the previously described method with slight modifications ( 21 ). The E. faecalis V583 was used as a host for phage isolation and propagation.…”

Insights into the novel Enterococcus faecalis phage: A comprehensive genome analysis

“…To explore the initial phases of infection, an absorption time assay was conducted [ 18 ]. In this experiment, mid-exponential phase VRE was subjected to exposure to the phage, with samples collected at 1-minute intervals over a 10-minute duration to monitor unabsorbed phages.…”

“…The effect of temperature on phage viability was evaluated by incubating the phage suspensions at different temperatures (-20, 4, 37, 50, 60, and 70°C) for 1h. Survival rates were determined using plaque assays [ 18 ].…”

“…In delving into the rich landscape of E. faecalis phages, research has uncovered a repertoire of lytic bacteriophages, including vB_EfaS_PHB08, vB_EfsS_V583, LG1, and others. These phages exhibit a commendable ability to target and disrupt E. faecalis biofilms, paving the way for potential applications in treating biofilm-related infections and dental root canal treatments [17][18][19][20]. The efficacy demonstrated in inhibiting biofilm formation and eradicating planktonic E. faecalis cultures attests to the promising role of these phages in clinical scenarios [12,20,21].…”

Characterization and Anti-Biofilm Activity of Lytic Enterococcus Phage vB_Efs8_KEN04 against Clinical Isolates of Multidrug-Resistant Enterococcus faecalis in Kenya

“…Studies have also shown that phages can be used to control biofilms formed by Enterococcus faecalis [23,61].…”