Abstract

Due to the emergence of pathogens that are resistant to antibiotics, antibiotic crisis is one of the biggest problems facing the world's population. Therefore, attention is now being directed towards investigating different approaches of treating bacterial infections. The bacterium's natural predator, the bacteriophage, is one of those options. This study aimed to identify the host range capacity of bacteriophages and separate them from various sewage samples that can lyse drug-resistant clinical bacterial isolates. The isolation of bacteriophage was done by Double Layer Agar Assay (DLAA) from 4 different sewage samples i.e. sewage sample from tertiary care hospital balkhu, tertiary care hospital nakhu, Chovar sewage outlet and Nayabazar sewage. For the isolation of phage, host organisms used were Multi Drug Resistant (MDR) Acinetobacter spp., Pseudomonas spp. and Escherichia coli resistant to Cefotaxime, Ciprofloxacin, Gentamicin, Imipenem, Amoxyclav, Ceftazidime. The plasmid extraction, 16S RNA analysis with PCR and Gel Agarose Electrophoresis, was done. Phage was isolated against Escherichia coli from both the hospitals sewage samples. Phage was also isolated against Pseudomonas spp. from Chovar sewage outlet but could not be sub-cultured because of its temperate properties. Phage could not be isolated against Acinetobacer spp. The host range analysis of Escherichia coli phages showed that the phages has narrow host range as they formed plaques against only one bacterium i.e. Klebsiella pneumoniae. Therefor, hospital sewage is probable place to find bacteriophages that can lyse MDR bacterial strains. Despite the isolated bacteriophage's potential in bactericidal activity, more research is necessary to fully understand it’s potential towards phage therapy.