Comparison of rapid quantitative PCR-based and conventional culture-based methods for enumeration of Enterococcus spp. and Escherichia coli in recreational waters.

摘要: Recreational water quality is currently monitored using culture-based methods that require 18 to 96 h for results. Quantitative PCR (QPCR) can be completed in less than 2 have been developed, but they could yield different results the conventional methods. We present two studies which samples were processed simultaneously Enterococcus spp. and Escherichia coli (EPA method 1600 Enterolert/Colilert-18) QPCR. The proprietary QPCR assays targeted 23S rRNA (Enterococcus spp.) uidA (E. coli) genes conducted lyophilized beads containing all reagents. In first study, developers 54 blind inoculated with sewage or pure cultures ambient beach samples. second study involved 163 by personnel. correlation between of EPA during (r2) was 0.69 spp., observed (r2, 0.87). During correlations similar. No false positives occurred either when QPCR-based used blank Levels reproducibility measured through coefficients variation similar both higher E. study. Regarding concentration at management decisions are issued State California, agreement 88%, compared 94% Enterolert. decision Colilert-18 94%. showing disagreement suggested an underestimation bias