A restriction map of the ~ 4.35 Mb circular chromosome of the vaccine strain BCG Pasteur was constructed by linking all 21 fragments, ranging in size from 6 to 820 kb, using specific clones that spanned the recognition sites as hybridization probes. The positions of 20 known genes were also established. Comparison of the resultant genome map with that of the virulent tubercle bacillus H37Rv revealed extensive global conservation of the genomes of these two members of the complex. Possible sites of evolutionary rearrangements were localized on the chromosome of BCG Pasteur by comparing the restriction profile with that of H37Rv. When selected cosmids from the corresponding areas of the genome of H37Rv were used as hybridization probes to examine different BCG strains, wild-type and H37Rv, a number of deletions up to 10 kb in size, insertions and other polymorphisms were detected. In addition to the known deletions covering the genes for the protein antigens ESAT-6 and mpt64, other genetic loci exhibiting polymorphisms or rearrangements were detected in BCG Pasteur.


Article metrics loading...

Loading full text...

Full text loading...

This is a required field
Please enter a valid email address
Approval was a Success
Invalid data
An Error Occurred
Approval was partially successful, following selected items could not be processed due to error