Detection of Esp Enterococcal Surface Protein and Bacteroides Markers in Water Samples

Finding the source of fecal pollution in various water resources has been becoming globally important.Molecular marker detection is the most reliable method for bacterial tracking.Since, rapidness is an important factor for the detection of water contamination, we have assessed the detection of water fecal contamination within a short period of time.In this study, twenty-two water samples, including 12 surface water from two rivers in East and West of Tehran (Iran) and 10 water samples from private wells were collected.In addition, five samples were collected from a Sewage Treatment Plant (STP) located in the West of Tehran.All of the samples were tested for the presence of fecal coliforms by Most Probable Number (MPN) method.Polymerase Chain Reaction (PCR) was performed for detection of enterococcal surface protein (Esp) and Bacteroides 16S rRNA.Direct extraction and colony extraction were simultaneously done for the detection of enterococcal contamination.The results showed that the coliform concentration for water samples ranged from >3->1100 MPN/100 mL.The PCR for esp was positive for 5 (23%) water samples.No samples were positive for 16S rRNA for Bacteroides with the exception of the samples obtained from the STP.Our results indicated that using PCR method directly following optimizing DNA extraction from environmental water sources is not suitable for the detection of human enterococcal contamination, while the use of colony extraction method is preferable.