Submitted to: International Virtual Conference on Infectious Diseases of Animals
Publication Type: Abstract Only
Publication Acceptance Date: April 20, 1997
Publication Date: N/A
Technical Abstract: Mycobacterium paratuberculosis (paratb) is the etiologic agent of paratuberculosis (Johne's disease), a chronic granulomatous enteritis in ruminants. Currently, improved diagnostics are needed because of the lack of rapid and accurate ID of M. paratb infection. An M. paratb genetic element was cloned, sequenced, and a 30 bp species-specific oligonucleotide e(oligo) was synthesized. As an internal control for all mycobacterial species, a 33 bp oligo for the mycobacterial recA gene was synthesized. Dioligonucleotide hybridization analysis identified mycobacterial species and specifically identified reference (ATCC 19698), bovine (cattle with Johne's disease), and human (patients with Crohn's disease) isolates of M. paratb. The M. paratb-specific oligo distinguished M. paratb isolates from related mycobacteria, including all closely related M. avium and M. intracellulare strains tested in this study. The M. paratb genetic element was also used in the development of a duplex polymerase chain reaction (dPCR) assay. Primers specific to the M. paratb sequence were synthesized. As an internal control to confirm that the organisms were mycobacteria, a second set of primers were synthesized based on the conserved 5' terminus of the mycobacterial recA gene. The experiments indicate that both the dioligonucleotide hybridization analysis and the dPCR assay are useful diagnostic tools to detect mycobacterial infection, specifically M. paratb.