Development of microbiological molecular diagnostic techniques for the rapid screening and identification of selected human bacterial pathogens and indicators

Abstract

This work, we believe, is a significant contribution to the development of molecular methods for the rapid detection of microorganism interacting with humans. Prevention, through the implementation of effective water microbiological monitoring to ensure human safety, and clinical diagnostics, can greatly benefit from such methods. Typical challenges in developing such techniques include maintaining or improving the sensitivity and specificity of the identification while automating and increasing the speed of the analysis. The work presented in this thesis has been performed at the Department of Molecular Biosciences at the University of Oslo in association with two Norwegian biotech companies, Colifast and Genpoint. The first part of the work is concerned with the development and validation of a semi automated rapid enzymatic method for the monitoring of a bacterial indicator group, the faecal coliforms, in recreational waters. This method was successfully validated by showing good agreement with traditional microbiological reference methods in a study which used a diversified and challenging pool of recreational water samples. This technology is in use today and has been further diversified into new applications by Colifast. In the second part of this work, a DNA based technique for the detection of selected bacterial indicator groups together with some of the most dangerous pathogenic strains of E. coli has been developed. This work was granted a patent in 2006. The third and last part of the work focused on developing and successfully validating an automated DNA preparation method for difficult samples, more specifically human urine in order to detect the important sexually transmitted pathogenic bacterium, Chlamydia trachomatis. The result of this last part is implemented in several Nordic hospitals.