Isolation, characterization and anti-biofilm efficacy of a novel Klebsiella pneumoniae phage

Abstract

Abstract The Multi-Drug-Resistant (MDR) Klebsiella pneumoniae (K. pneumoniae) is an important pathogen that threatens public health directly with life threatening infections. The need for the development of new effective and safe alternative treatments for these infections is crucial. Therefore, the interest in phage therapy as a promising alternative is increasing. Here, a novel phage named ΦAYH was isolated from the Tigris River water, Baghdad, IRAQ near sewage of Baghdad Medical City with its specific host from the same site. Phage ΦAYH belongs to Podoviridae family in the order Caudovirales. The ΦAYH maintained stability at different temperatures (-10- 60°C) and pH values (5-11). For one-step growth, latent period was 10 min with burst size ~64 virions/ cell at MOI 10. The phage was able to lyse 8 from 32 clinical K. pneumoniae isolates in vitro. The SDS-PAGE test revealed one major structural protein and different structural proteins ranging from 28 to 89 kDa in size. The phage host and 32 clinical K. pneumoniaeisolates were tested for phenotypic identification and antibiotics profile by VITEK-2 system and genotypically using rpob gene. All clinical K. pneumoniae isolates showed resistance to the most antibiotics tested while phage host was resistant only to amoxicillin. Biofilm production by all clinical isolates including the host isolate was tested. These isolates showed different ability as following: 72.72 % as weak, 6.06% as moderate, and 21.21% as strong biofilm producer. Together these results demonstrate that ΦAYH is a promising alternative against MDR K. pneumoniae.