Submitted to: Journal of Bacteriology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 12/21/2005
Publication Date: 3/1/2006
Citation: Marsh, I.B., Bannantine, J.P., Paustian, M., Tizard, M.L., Kapur, V., Whittington, R.J. 2006. Genomic Comparison of Mycobacterium avium subsp. paratuberculosis Sheep and Cattle Strains by Microarray Hybridization. Journal of Bacteriology. 188(6): 2290-2293. Interpretive Summary: This study represents an international collaboration to discover genetic difference between sheep strains and cattle strains of Mycobacterium avium subspecies paratuberculosis, the agent that causes Johne’s disease. It has long been known that the sheep strains behave quite differently when compared to the cattle strains. For examples, the sheep strains grow even slower than the already slow cattle strains. However, no genotypic differences were previously known that could account for these divergent phenotypes. We used the recently developed whole-genome microarray of M. paratuberculosis to identify a total of 24 genes that are absent in the sheep strains. It is likely that the absence of these genes in the sheep strains may be responsible for the slow growth and other phenotypic differences observed between cattle and sheep strains.
Technical Abstract: Microarray-based comparisons of three Mycobacterium avium subsp. paratuberculosis isolates, including one sheep strain and two cattle strains, identified three large genomic deletions in the sheep strain, totaling 29,208 bp and involving 24 open reading frames. These deletions may help explain some of the differences in pathogenicity and host specificity observed between the cattle and sheep strains of Mycobacterium avium subsp. paratuberculosis.