Fig. 2.

Amplification of Listeria monocytogenes EGDe and ΔprfA DNA using various polymerases under prfA-standard-conditions. Calibration curves (ranging from 1.58 × 10¹ to 1.58 × 10⁶ ITMN per reaction, copies on the x-axis and Cq on y-axis) amplified under prfA-standard-conditions (only AmpliTaq Gold 10 min denaturation) with different polymerases/mastermixes (grey circles) were compared with the calibration curve amplified by Platinum Taq polymerase (black squares). All duplex reactions were displayed on top of each other with the white background for the prfA assay and grey for the ΔprfA assay. Rsq values and efficiencies (in %) were indicated for each polymerase/mastermix in the respective graph with Rsq values <0.98 and efficiencies more than 105% and less than 90% presented in grey. Rsq and efficiency for Platinum Taq polymerase are 1.000 and 96.7% in the prfA assay and 1.000 and 94% in the ΔprfA assay. No Cq were represented with white circles. One of two independent experiments including each six standards in single reactions is demonstrated. All PCRs except AmpliTaq Gold were carried out in the same run.