How low can you go

Finding the Needle in a Haystack of DNA: Ultra-Sensitive Detection of E. coli and Enterococci in Drinking Water.

Drinking water is tested daily for traces of faecal contamination. According to the legal standard, drinking water may not contain any E. coli or enterococci—one bacterium of this species is already too many. Traditional culture methods are used by drinking water laboratories for this purpose, but these require relatively long analysis times and are limited in sensitivity and specificity. As an alternative, we have developed molecular detection techniques, such as PCR-based methods, that can demonstrate the presence of faecal indicator organisms faster and with higher sensitivity. However, the challenge remains: detecting the presence of a single E. coli or enterococci in a background of millions of other DNA fragments requires very robust and validated analysis methods.

In this talk I will share our experiences with the development and validation of such molecular methods. I will discuss how we managed to reach the detection limits required by law, which technical and practical obstacles we encountered, and which lessons we learned with a view to future applications in drinking water diagnostics.
Speaker: Adrie Atsma

Register