Isolation and Characterization of Lytic, Morpholoical and pH Resistanece Properities of Two Escherichia coli O111 - Specific Phages from Sewage Samples

Abstract

In recent years, bacteriophages have piqued interest as a potential alternative antimicrobial therapy for bacterial infections. Because phage therapy is the most promising biological remedy of this period, its therapeutic success is a source of concern. Hence, the present study was aimed to isolate the potential bacteriophages against Escherichia coli O111 fromt sewage samples and to analyze their lytic and morphological traits. Bacteriophages were isolated from swage samples using the double agar overlay method. Isolated phages were purified by diluting in the SM-buffer and filtering through 0.22??m filter. After purification through glycerol gradient The two phages (named P1 and P2) were visualized by transmission electron microscope ,  both phages appeared to belong to Myoviridae characterized by icosahedral heads, necks and contractile tails with tail fibers. The two phages were resistant to pH from 5 to 9 to an acidic and alkaline environment. Therefore, these phages may be utilize as biocontrol agents alternative for antibiotic but certainly further studies (especially whole sequencing and bioinformatic analysis of the phage genomes) are required as well as assessment of their activity in animals particularly cattle which are major reservoirs of this pathogens.