Detection of the beta-lactamase gene in commercial Taq polymerase.

<p>Four dilutions of Amplitaq DNA polymerase were tested with primers for the beta-lactamase gene in the presence of 10³ pUC19 plasmids (labeled 1000 pUC19 genomes) or H₂O.</p

Detection of <i>Pseudomonas fluorescens</i> at high and low Taq polymerase concentrations.

<p>Bacterial detection with 0.5 Units (A) or 0.05 Units (B) Qiagen Taq DNA polymerase with 16S350B assay on samples containing 10³, 10², 10¹ and zero <i>Pseudomonas fluorescens</i> bacteria. A composite of A and B is shown in C.</p

Approximating the copy number of 16S rDNA in commercial Taq polymerases.

<p>Six DNA polymerases were used with primers for 16S rDNA on 7 serial 10-fold dilutions of E. coli genomic DNA (10 ng to 10 fg) with no added DNA in the 8^th sample. The least squares fit equation for each dilution series was used to assign a value to the signal from the 8^th sample, which contains Taq-associated DNA only. The efficiency of the reaction was determined from the slope of the linear fit plotting the base10 log of the DNA concentration vs. the threshold cycle. A slope of −3.322 indicates an average doubling rate of “2,” which is approximately 100% efficiency (2̂3.322∼10). The rDNA values assigned are for “E. coli equivalents.”</p

Detection of bacterial DNA in six Taq polymerases.

<p>Four dilutions of six DNA polymerase were tested with primers for 16S rDNA in the presence of 100 pg (∼10̂5 16S rDNA) E. coli genomic DNA (circled) or H₂O.</p

Alignment of 16S primers on the genomes of 12 bacterial sequences.

<p>Four bacteria, <i>M.luteus, S.griseus, V.fischeri</i> and <i>M.catarrhalis</i> were detected at least at 100-fold greater levels with LP2 than with LP1, presumably due to the lack of basepairing of the 3′ base of LP1. The key beneath the figure provides the GenBank records for the sequences shown.</p