[Evaluation of urease and beta-glucosidase activity for the practical identification of mycobacteria (author's...

The urease and the beta-glucosidase for the identification of the mycobacteria were evaluated using 1,019 strains received for reference purposes in this laboratory in 1978. We found that the urease test was useful in the differential identification of BCG which, contrary to Mycobacterium bovis, gave a strong positive reaction in 3 h. The test was also useful to discriminate M. scrofulaceum from pigmented strains of M. avium. The beta-glucosidase test discriminated between M. tuberculosis and M. bovis and was useful to distinguish the niacine-positive strains of M. africanum which were usually negative in this test. The beta-glucosidase test was particularly useful in the differential identification of M. fortuitum and M. chelonei. In this report, the frequency distribution of the species which were submitted to this laboratory in 1978 was also shown and the results obtained for each of the conventional test procedures was presented.