Zumárraga Martin, Bigi Fabiana, Alito Alicia, Romano María I, Cataldi Angel
Instituto de Biotecnología, Centro de Investigaciones en Ciencias Veterinarias, Instituto Nacional de Tecnología Agropecuaria, 1708 Moron, Argentina.
Instituto de Patobiología, Centro de Investigaciones en Ciencias Veterinarias, Instituto Nacional de Tecnología Agropecuaria, 1708 Moron, Argentina.
Microbiology (Reading). 1999 Apr;145 ( Pt 4):893-897. doi: 10.1099/13500872-145-4-893.
Southern blotting, sequence analysis and PCR experiments showed that Mycobacterium bovis and Mycobacterium bovis BCG lack a 12.7 kb fragment present in the genome of Mycobacterium tuberculosis. This region is 337 bp downstream of the RD2 region, which was previously described as being absent from some M. bovis BCG strains. The 12.7 kb fragment should be useful as a target for a PCR test to differentiate M. tuberculosis and M. bovis. An analysis of the 12.7 kb region suggests that it represents a deletion in M. bovis rather than an insertion in M. tuberculosis. The deletion removes most of the mce-3 operon, one of four highly related operons which may be involved in cell entry, and therefore it may contribute to differences in virulence or host range in the two species.
Southern印迹、序列分析和PCR实验表明，牛分枝杆菌和卡介苗菌株缺乏结核分枝杆菌基因组中存在的一个12.7 kb片段。该区域位于RD2区域下游337 bp处，此前曾报道一些卡介苗菌株中不存在该区域。12.7 kb片段应可作为PCR检测的靶点，用于区分结核分枝杆菌和牛分枝杆菌。对12.7 kb区域的分析表明，它代表牛分枝杆菌中的一个缺失，而非结核分枝杆菌中的一个插入。该缺失去除了mce - 3操纵子的大部分，mce - 3操纵子是四个高度相关的操纵子之一，可能参与细胞进入过程，因此它可能导致这两个物种在毒力或宿主范围上的差异。
