vB_EcoM_kmuOR AND vB_EcoM_kmuGH: TWO BROAD HOST RANGE COLIPHAGES EFFECTIVE AGAINST ESCHERICHIA COLI O157:H7 AND SHIGELLA FLEXNERI

Abstract

E. coli O157:H7 is a foodborne pathogen mostly related to consumption of meat and vegetables. Although using antibiotics is not recommended in treatment of infections caused by this pathogen, antibiotic resistant isolates are reported. This has encouraged researchers to find alternative methods to treat and effective approaches to prevent the E. coli O157:H7 infections. Phage therapy is one of the techniques with therapeutic and biocontrol applications. The aim of this study was to find effective phages capable of lysing this pathogen. Twenty samples were searched for phages against E. coli O157:H7. The host range of the isolated phages was determined. The phages with broader host range were selected for structural study. The stability in different temperature and pH values were also performed. Phages kmuOR and kmuGH could lyse two strain of E. coli O157:H7, some clinical non-O157 E. coli strains, and a strain of Shigella flexneri, another enteric pathogen. Transmission electronic micrograph revealed that both phages belong to Myoviridae family. The two phages were resistant to pH 3 to 9.5 and temperatures 4-50°C and able to prevent the growth of E. coli O157:H7 in LB medium. Further study can prove the suitability of these phages as biocontrol or phage therapy agents.