Abstract

ISOLATION, CHARACTERIZATION AND ANTIBACTERIAL ACTIVITY OF BACTERIOPHAGES AGAINST MULTIPLE ANTIBIOTIC RESISTANT ESCHERICHIA COLI INVOLVED IN URINARY TRACT INFECTIONS

Shahad Raad Mezaal* and Hassan M. Naif

Abstract

Bacteriophages, as bacterial phages, are very species-specific with regard to their hosts and usually only infect a single, bacterial species, or even specific bacterial strains within a species. The study was carried out using 820 samples comprised of 100 stool and 720 urine from UTI infected patients. Four hundred twenty isolates of E.coli (51%) were isolated. It was found to be more frequent in female (73.17%) and less prevalent in males (28.82%) as determined by microbiological, biochemical and vitek-2 system and confirmed by detection of 16SrRNA. The sensitivity test carried out on E.coli isolates against 16 different antibiotics revealed resistance at a high ratio for more than nine antibiotics (data presented in a separate report). As a consequence of the challenge of multiple antibiotic resistance to the public health worldwide, a highly effective phage alternative therapy is sought in this study. The antibacterial activity of coliphages were assessed against 15 multiple antibiotic resistant E.coli isolates obtained from children with UTI. All isolates (100%) tested were sensitive to bacteriophge lysis effect. This indicated that bacteriophge activity as anti-bacterial therapy was specifically effective against E. coli isolates. The electron microscopy revealed three types of viruses named: Siphoviridae, Podoviridae, and Microviridae. The three types of colipahges were assessed for their stability, physical, chemical sensitivity/durability. Coliphages stability with no change in titre was its best at 4ºC, then declines at other temperatures tested at 25, 37, and 45ºC. The phage titer decreased with the length of exposure time to sun light from clear (1011) to 150. Incubating phage suspensions with alcohol, chloroform, detergent and hypochlorite at 37ºC resulted in reduction of phage activity by 10% at 12h with chloroform. On the other hand, ethanol showed the lowest inhibiting effect on the infectivity of tested coliphages. Detergent has reduced infectivity by 10% at different time exposure. While hypochlorite had a 1.25% effect on phage infectivity.

Keywords: Urinary tract infection, Bacteriophage, E. coli; multiple antibiotic resistant.