Bacteriophages inhibit biofilms formed by multi-drug resistant bacteria isolated from septic wounds

Abstract

Globally, indiscriminate use of antibiotics contributed to the development of antibiotic resistance by the majority of microbial pathogens. As an alternative to antibiotics, using bacteriophages as antibiofilm agents to tackle multi-drug resistant bacteria has gained importance in recent years. In the present study, we explored the ability of bacteriophages to inhibit biofilm formation under various conditions. Under dynamic condition (DR), wherein the medium is a renewal for every 12 h amount of biomass produced (0.74 {+/-} 0.039), log10 CFU count (6.3 {+/-} 0.55) was highest when compared to other physical conditions tested. Biomass of biofilms produced by Staphylococcus aureus, Pseudomonas aeruginosa, Klebsiella pneumoniae, and Escherichia coli drastically reduced when incubated for 2 or 4 h with bacteriophages vB_SAnS_SADP1, vB_PAnP_PADP4, vB_KPnM_KPDP1, and vB_ECnM_ECDP3 respectively at the time points tested (24, 48 and 72 h). Among the phages, vB_ECnM_ECDP3 effectively inhibited the biomass of biofilm when incubated for 2 h (0.35 {+/-} 0.04, (44 %) (p < 0.0001) or 4 h (0.17 {+/-} 0.015, (21.5%) (p<0.0001). Bacteriophages of E. coli (vB_ECnM_ECDP3) P. aeruginosa (vB_PAnP_PADP4), K. pneumoniae (vB_KPnM_KPDP1) and S. aureus (vB_SAnS_SADP1) also significantly inhibited the biomass of biofilm formation as evidenced by Scanning Electron Microscopy and Confocal laser scanning microscopy.