FIG. 4.

Comparison of the numbers of O. formigenes CFU in a bacterial culture detected by culture and QC-PCR. An overnight culture of O. formigenes OxB containing approximately 0.7 × 10⁸ CFU/ml, as determined by optical density at 600 nm, was serially diluted 10-fold. DNA isolated from each dilution was used in QC-PCR. Log equivalences of O. formigenes to template band intensities were determined and compared to the estimated number of CFU for each dilution.