Nucleotide sequence of MPB63 gene in Mycobacterium bovis BCG Tokyo.

Mycobacterium bovis BCG has been used for the prevention of tuberculosis and as therapy for bladder tumor. MPB63 in M. bovis BCG is one of the immunogenic proteins and is secreted in large quantities. Therefore, it is of interest that the MPB63 gene be examined for the determination of its nucleotide sequence. A fragment of 820 base pairs (bp) including the MPB63 gene was prepared by amplification using polymerase chain reaction (PCR) employing M. bovis BCG Tokyo chromosomal DNA as a template and its nucleotide sequence was determined. The nucleotide sequence of mpb63 in M. bovis BCG was then compared with that of mpt63 in M. tuberculosis. The result indicated that the nucleotide sequences between two protein genes were quite agreeable in the genes' structural and upstream regions, except that one base change from C in mpt63 to G in mpb63 was detected in the downstream trailer sequence. This suggests that the genetic information of M. bovis BCG is not entirely identical to that of M. tuberculosis, although the characteristics of both microorganism are very similar to each other.