Catalases, peroxidases, and superoxide dismutases in Mycobacterium leprae and other mycobacteria studied by crossed immunoelectrophoresis and polyacrylamide gel electrophoresis.

The five mycobacteria Mycobacterium lepraemurium, M. leprae, M. bovis BCG, M. smegmatis, and M. intracellulare were studied. Catalase and peroxidase activities were demonstrated in polyacrylamide and crossed immunoelectrophoresis gels for M. lepraemurium, M. intracellulare, and BCG, but not for M. leprae. Peroxidase and catalase activities were associated with the same precipitate line in crossed immunoelectrophoresis for M. lepraemurium, M. intracellulare, and BCG, showing that in these mycobacteria the two enzyme activities resided in the same molecule. M. smegmatis peroxidase and catalase activities were closely associated on polyacrylamide gel electrophoresis, but on the crossed immunoelectrophoresis catalase and peroxidase activities were associated with two different precipitate lines. Catalases without peroxidase activity were demonstrated in crossed immunoelectrophoresis and polyacrylamide gel electrophoresis in M. intracellulare and M. smegmatis. The catalase without peroxidase activity in M. intracellulare was heat resistant and therefore classified as an m-catalase. In M. smegmatis the catalase without peroxidase activity was only partially heat resistant. All of the catalases with peroxidase activity were heat-sensitive t-catalases. Superoxide dismutase activity in the crossed immunoelectrophoresis was associated with the M. leprae antigen no. 4 and with cross-reacting antigens in the other mycobacteria studied. Several superoxide dismutases were demonstrated in Mycobacterium duvalii. They were antigenically different from the other superoxide dismutases in this study, as shown by lack of reactivity with a monospecific antibody to M. lepraemurium superoxide dismutase. Molecular weights were estimated for all the enzymes in this study by sodium dodecyl sulfate-polyacrylamide gels.