Amplification plot (A) and standard curve (B) of the optimized real-time PCR assay for the Mptb52.16 target. Based on the molecular weight of the genome of MAP strain K-10 (GenBank accession number AE016958), 1 ng DNA equals 9.59 × 105 copies of the entire genome. The MAP-specific target Mptb52.16 is a single-copy gene. Thus, this figure equals the number of PCR targets per ng. The dilution series ranged from 9.59 × 105 to 9.59 × 100 copies of the genomic DNA from MAP strain CIP 103974 per PCR. Fifty copies of an IAC were added to each reaction. The MAP-specific probe was detected in the FAM channel, whereas the IAC-specific probe was detected in the HEX channel.