Identification of human fecal pollution: detection and quantification of the human specific HF183 Bacteroides 16S rRNA genetic marker with real-time PCR

A real-time PCR assay for the detection and quantification in fecal and environmental samples of the human specific HF183 Bacteroides 16S rRNA genetic marker previously found by Bernhard & Field (2000a) , was developed and proved to be more sensitive than the conventional HF183 PCR. The limit of detection in canal water was https://www.w3.org/1998/Math/MathML" display="inline"> 1.94 × 10 2 copies per https://www.w3.org/1998/Math/MathML" display="inline"> μ I DNA extract and the limit of quantification was https://www.w3.org/1998/Math/MathML" display="inline"> 5.83 × 10 2 copies per https://www.w3.org/1998/Math/MathML" display="inline"> μ l DNA extract. The intra- and intervariability coefficients of the real-time assay were less than https://www.w3.org/1998/Math/MathML" display="inline"> 1 % and https://www.w3.org/1998/Math/MathML" display="inline"> 3 % , respectively. The amount of marker copy number present per https://www.w3.org/1998/Math/MathML" display="inline"> g of wet human feces varied from https://www.w3.org/1998/Math/MathML" display="inline"> 10 2 to https://www.w3.org/1998/Math/MathML" display="inline"> 10 8 between different individuals. The amount of marker copy number present in wastewater treatment plant influent varied from https://www.w3.org/1998/Math/MathML" display="inline"> 10 8 to https://www.w3.org/1998/Math/MathML" display="inline"> 10 9 per liter. The marker persisted upto 6 days at https://www.w3.org/1998/Math/MathML" display="inline"> 28 ∘ C . Whereas, the limit of detection was not reached after 24 days of incubation at 4 and https://www.w3.org/1998/Math/MathML" display="inline"> 12 ∘ C .