Isolation and characterization of lytic bacteriophage from waste water to control clinical multidrug resistant Klebsiella pneumoniae

Klebsiella pneumoniae is an opportunistic bacterium which can cause nosocomial, community acquired, and respiratory infections. It also has the biofilm forming ability which is difficult to treat through antimicrobial drugs. Therefore, an alternative therapy to antibiotics, such as bacteriophages, are required to control this biofilm producing, multi-drug resistant bacterium. The aim of this study was to isolate and characterize a lytic bacteriophage to control the multi drug resistant K. pneumoniae-3206 planktonic cells and biofilm. Phage RAM-1 was isolated from wastewater. It was characterized through transmission electron microscopy and was classified to be a member of the Podoviridae family. SDS-PAGE analysis showed that the phage consisted of approximately eighteen different proteins (13–200 ​kDa). Its genome was found to be ds DNA of about of ≈36 ​kb. Phage RAM-1 displayed good heat (37–65 ​°C) and pH (5–11) stability. Phage RAM-1 showed promising activity against the 24-, 48-, and 72-h biofilms made (underneath static conditions along with media renewal) by K. pneumoniae-3206. After a 6-h phage treatment, about 2.5, 3.6 and 4-log reductions were observed respectively. Thus, we concluded from this study that RAM-1 has potential in eradicating both bacterial planktonic cells and biofilm. However, to achieve complete bacterial eradication, a phage cocktail (a combination of two or more phages) will be more promising.