Molecular Characterization of Pigmented and Nonpigmented Isolates of Mycobacterium avium subsp. paratuberculosis

Abstract

ABSTRACT Five pigmented isolates of Mycobacterium avium subsp. paratuberculosis were examined by pulsed-field gel electrophoresis (PFGE), IS 900 restriction fragment length polymorphism (IS 900 -RFLP), and IS 1311 polymorphism analysis using PCR. All of the pigmented isolates exhibited one of three distinct PFGE profiles with Sna BI, designated 9, 10, and 11, and with Spe I, designated 7, 8, and 9, which generated three multiplex profiles designated [9-7], [10-8], and [11-9]. All of the pigmented isolates had the same IS 900 -RFLP Bst EII and Pvu II profiles. The IS 900 -RFLP Bst EII profile was new, but the IS 900 -RFLP Pvu II profile corresponded to Pvu II type 6 of a sheep strain described by Cousins and colleagues (D. V. Cousins, S. N. Williams, A. Hope, and G. J. Eamens, Aust. Vet. J. 78:184-190, 2000). IS 1311 -PCR analysis typed all of the pigmented isolates as sheep (S) strains. The genetic relationship between pigmented and nonpigmented isolates was investigated by using multiplex PFGE data from the analysis of both the 5 pigmented isolates and 88 nonpigmented isolates of M. avium subsp. paratuberculosis from a variety of host species and geographic locations. It was possible to classify the isolates into two distinct types designated type I, comprising the pigmented isolates, and type II, comprising the nonpigmented isolates, which exhibit a very broad host range.