SEQUENCE HETEROGENEITY OF AN MPB70 GENE ANALOG IN MYCOBACTERIUM-KANSASII

The protein antigen MPB70 is a major component of culture supernatants of Mycobacterium bovis and Is an active ingredient of bovine PPD used for skin-testing cattle for tuberculosis. we have shown that Mycobact erium kansasii possesses a similar gene that cross-reacts in a PCR tes t for M. bovis. Single strand conformational polymorphism analysis, an d the DNA sequence of the PCR product, shows differences between M. ka nsasii strains, supporting the suggestion that M. kansasii is not a ho mogeneous species.