Tetrazolium method for studying the catalytic properties of oxidoreductases in cellular organelles immobilized on glass surfaces.

A new quantitative method allowing the measurement of the activity of oxidoreductases, as well as the study of their catalytic properties, is proposed. The method is based on photometering a smear of cellular organelles in the course of incubation in medium containing the reductase substrate and an artificial electron acceptor, tetrazolium salt. Catalytic properties of succinate:p-nitrotetrazolium violet reductase, as revealed on the smears, are shown to be identical to those of the reductase in mitochondrial suspension. Under similar conditions the maximal oxidation rate of succinate with p-nitrotetrazolium violet is the same as that in the presence of an acceptor of another type, Wurster's blue. The method allows the study of a number of reductases.