Ferdowsi University of Mashhad

Document Type : Research Articles


Department of Biology, Faculty of Basic Sciences, University of Maragheh, Maragheh, Iran



Urinary tract infection, as one of the most prevalent bacterial infections, affecting millions of people yearly worldwide. Due to control of increasingly antibiotic resistant infections, it is needed to introduce the alternative approaches such as phage therapy. In this study, isolation, purification and enrichment of eight lytic bacteriophages against antibiotic-resistant Escherichia coli strains originated from human urinary tract infections were performed using double layer agar method. Molecular analysis of the bacteriophages was performed using two endonucleases enzymes (EcoRV and XbaI). Then two of eight isolated bacteriophages with the highest host range were more characterized to determine their morphology, one step growth, latent period, burst size and stability in environmental parameters (temperature and pH). Eight isolated bacteriophages showed high genome variation in enzyme digestion process. Two phages with the broadest host range (PEcMa2/17 and PEcMa3/17) showed effective lytic activity against five isolates. In electron microscopy, selected phages were belonged to Siphoviridae and Myoviridae family. Latent period in both of the propagated phages were 15 min and the burst size was estimated to 100 pfu/ ml and 120 pfu/ml in PEcMa2/17 and PEcMa3/17 respectively. Both of the phages showed more than 50% stability at 37 ºC and lower used temperatures and they were survived efficiently in pH=7. The bacteriophages showed strong antibacterial potential against Escherichia coli from UTIs, but as candidates for phage therapy, more characterization such as molecular analysis and experimental assays are needed before therapeutic applications.