Application of the polymerase chain reaction to the identification of Escherichia coli and coliforms in water.

The polymerase chain reaction (PCR) has been applied to the identification of Escherichia coli and coliforms after overnight growth using two sets of primers described previously. The primer set for E. coli, which was derived from the uid A gene, correctly identified all E. coli strains tested. The sequence was also identified in five non-E. coli coliforms. The coliform primer set correctly identified approximately 70% of the coliforms tested. We conclude that PCR can be used for the rapid identification of E. coli using the primers described here but that further work is required accurately to define a new primer set for the coliform group.