Development of a polymerase chain reaction test to confirm Mycobacterium avium subsp. paratuberculosis in culture.

A polymerase chain reaction (PCR) assay for confirmation of Mycobacterium avium subsp. paratuberculosis was developed using the primer set derived from ISMav2. The PCR product was 494 base pairs (bp) and could be digested with ClaI, which produced 311- and 183-bp fragments. No amplification of 494-bp DNA fragment was detected from DNA of other Mycobacterium spp., including Mycobacterium avium complex, other bacteria, including Escherichia coli, Pseudomonas aeruginosa, Actinobacillus pleuropneumoniae, Leptospira interrogans serovar pomona, Corynebacterium pseudotuberculosis, Salmonella typhimurium, Borrelia burgdorferi, and Staphylococcus aureus, and the Scedosporium sp. This PCR assay could detect 5-8 genome equivalents.