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Bovine tuberculosis is caused by Mycobacterium bovis, a mycobacterium highly similar to M. tuberculosis that belongs to the M. tuberculosis complex. The main host of M. bovis is cattle but it also affects many other mammalians including humans. Tuberculosis in humans caused by either M. bovis or M. tuberculosis is clinically hard to distinguish. During 2004-2005, samples from 448 patients with diagnosis of TB were collected from different regions of Argentina. The PRA technique identified 400 isolates with representative patterns of mycobacterium. The predominant ones were the M. tuberculosis complex, the M. avium-M. intracellulare complex and M. gordonae. Samples with M. tuberculosis complex PRA restriction profiles were analyzed with a multiplex PCR to differentiate between M. tuberculosis and M. bovis. Multiplex PCR identified nine M. bovis. The results allowed the possibility to establish that 2% of pulmonary tuberculosis was due to M. bovis. Isolates of M. bovis from humans were examined using spoligotyping. These isolates presented five different spoligotypes. The main spoligotype was also the most frequently one found in cattle. The remaining human spoligotypes (grouped in clusters) are occasionally found in cattle. Variable number tandem repeat (VNTR) analysis identified five different patterns. By combining the results of spoligotyping and VNTR analysis, we were able to differentiate seven M. bovis isolates. The remaining two M. bovis samples showed the same spoligotype and VNTR profile and belonged to household contacts. An MDR-M. bovis was isolated from the samples of these household contacts. The identification of two epidemiologically linked cases of human M. bovis infection suggests person-to-person transmission of an MDR-M. bovis.

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Genetic differences between Mycobacterium bovis and M. tuberculosis were identified. We found (i) a deletion of Rv3479 specific to M. bovis, (ii) that the rpfA gene is shortened to various extents in M. bovis, and (iii) an insertion in Rv0648 and a duplication of lppA common in M. tuberculosis complex isolates.Mycobacterium bovis, the agent of bovine tuberculosis, belongs to the M. tuberculosis complex (MTBC), whose members are closely related and show high similarity at the DNA level (2,5,8). However, despite this close relationship, they show a large variability in their phenotypic properties, epidemiology, and incidence in human tuberculosis.The M. tuberculosis H37Rv (4) and M. bovis AF2122/97 (7) genomic sequences were compared using blastn and MSPcrunch (11) software and visualized with Artemis Comparison Tool version 4.0 for Apple (ACT, www.sanger.ac.uk /Software).The criteria used to select loci for further studies were that they were not IS6110 insertions, PE-PPE family genes (4), single-nucleotide polymorphisms, or previously published regions of difference (1, 2). Four loci were selected: Rv3479, Rv0648, lppA and rpfA. In all these cases, the polymorphisms involved only one gene. The bioinformatic analysis yielded the following information: ϽOL TYPE ϭ "a"Ͼ.(i) Rv3479. The Rv3479 gene encodes a hypothetical transmembrane protein of 3,225 bp in both M. tuberculosis H37Rv and CDC 1551 (6). However, the orthologue gene in M. bovis AF2122/97 carries a 714-bp deletion which starts at base 1254 from the ATG start codon (Fig. 1). This deletion originates two smaller open reading frame with sequences almost identical to Rv3479.(ii) rpfA (Rv0867). rpfA is a 1,221-bp gene that encodes for a possible resuscitation-promoting factor. The central part of the protein contains APADLAPP repeats (9). The sequenced M. bovis strain lacks part of these repeats (Fig. 1) due to a 240-bp in-frame deletion. These domains are not deleted in M. tuberculosis CDC 1551.(iii) Rv0648. M. bovis AF2122/97 has a 533-bp in-frame insertion in the Rv0648 gene relative to M. tuberculosis H37Rv (Fig. 1). This characteristic is similar to that of the RvD elements (3) (http://www.pasteur.fr/recherche/unites/Lgmb-/Deletion.html). However, the sequence of this insertion indicates that it is not one of the five previously described RvD (3) or TbD1 (2) elements. We propose to refer to this fragment as RvD6. This extra fragment is also present in M. tuberculosis CDC 1551.(iv) lppA and lppB. The lppA and lppB genes, encoding lipoproteins, are highly similar. lppA is duplicated in M. bovis AF2122/97 with respect to M. tuberculosis H37Rv (Fig. 1). Interestingly, lppA is also duplicated in M. tuberculosis CDC 1551.The four genes were BLAST searched in the M. smegmatis, M. avium, M. marinum, and M. leprae genomes (data not shown). Orthologues of rpfA genes exist in all of them. However, no Rv3479 and lppA orthologues were found in these mycobacteria. The orthologues of Rv0648 present in M. smegmatis, M. avium, and M. marinum have a size similar to that o...

We here identified for the first time the presence of Mycobacterium avium paratuberculosis (MAP) sheep (S) strain in Argentina. IS900 polymerase chain reaction (PCR) was positive. The S strain was compared with MAP cattle (C) strains by using IS1311 PCR-restriction endonuclease analysis (PCR-REA), multiplex PCR and restriction fragment length polymorphism (RFLP) analysis.