الفهرس | Only 14 pages are availabe for public view |
Abstract The present study was done to investigate the effect of bacteriophages on biofilm associated enterococcal urinary tract infections. One hundred enterococcal clinical isolates were obtained from urinary tract infected patients. The isolates were identified and tested for biofilm formation. The obtained results revealed that all the isolates are Enterococcus faecalis from which 35 isolates were strong biofilm formers. Strong biofilm-forming Enterococcus feacalis urinary tract pathogens (n=35) were used to determine the lytic spectrum of 6 bacteriophages isolated from sewage samples. Only 17 Enterococcus feacalis isolates gave a variable level of susceptibility (clear plaques) to the tested bacteriophages from which 5 isolates were susceptible to all of them. The isolated enterococcal phages are characterized by a wide range of temperature (30-90°C) and pH (3-10) stability. They belong to the order Caudovirales, from which 4 bacteriophages (EPA, EPB, EPD, EPF) belong to the family Myoviridae, and the other two phages (EPC, EPE) belong to the family Siphoviridae. In addition, they have promising antibiofilm activity against the tested strong-forming biofilm E. faecalis isolates. The enterococcal phages (titer 107) reduced the formed biofilms to a range of 38.02-45.7% and eradicated the preformed biofilms to a range of 71.0- 80.0%, as compared to the control. The same promising activities were obtained in studying the anti-adherent effect of the tested bacteriophages on the adherence of bacterial cells to the surface of urinary catheter segments. They reduced the number of adherent cells to a range of 30.8-43.8% and eradicated the pre-adherent cells to a range of 48.2-71.1, as compared to the control. Further studies were carried out to evaluate the antibiofilm activity of phage combination. The obtained results showed an increase in the antibiofilm activity as compared to the activity of each phage alone. Overall, the obtained promising antibiofilm activity makes these phages good candidates for potential application in preventing and treating biofilm-associated Enterococcus faecalis infections in vitro. |