Lytic Bacteriophages Against Bacterial Biofilms Formed by Multidrug-Resistant Pseudomonas aeruginosa, Escherichia coli, Klebsiella pneumoniae, and Staphylococcus aureus Isolated from Burn Wounds

Phage (New Rochelle). 2021 Sep 1;2(3):120-130. doi: 10.1089/phage.2021.0004. Epub 2021 Sep 17.

Abstract

Background: Use of bacteriophages as antibiofilm agents to tackle multidrug-resistant bacteria has gained importance in recent years. Materials and Methods: In this study, biofilm formation by Staphylococcus aureus, Pseudomona aeruginosa, Klebsiella pneumoniae, and Escherichia coli under different growth conditions was studied. Furthermore, the ability of bacteriophages to inhibit biofilm formation was analyzed. Results: Under dynamic growth condition, wherein the medium is renewed for every 12 h, the amount of biomass produced and log10 colony-forming unit counts of all bacterial species studied was highest when compared with other growth conditions tested. Biomass of biofilms produced was drastically reduced when incubated for 2 or 4 h with bacteriophages vB_SAnS_SADP1, vB_PAnP_PADP4, vB_KPnM_KPDP1, and vB_ECnM_ECDP3. Scanning electron microscopy and confocal laser scanning microscopy analyses indicated that the reduction in biomass was due to the lytic action of the bacteriophages. Conclusions: Results of our study reinforce the concept of developing bacteriophages as alternatives to antibiotics to treat bacterial infections.

Keywords: alternative antimicrobials; antibiotic resistance; bacteriophages; biomass; colony-forming units; multidrug resistance.