Preparation of detergent permeabilized Bakers’ yeast whole cell catalase

Whole cells of bakers’ yeast (Saccharomyces cere6isiae) exhibited very low catalase activity (16 U g-1). Various treatments altered membrane permeability and increased cellular catalase activity. Treatment with cetyltrimethylammonium bromide (CTAB)yielded maximum catalase activity (51000 U g-1) followed by digitonin (27072 U g-1). After permeabilization of the membrane,
the catalase slowly leaks out of the cells. The half-life of intracellular catalase in CTAB-permeabilized cells was 3.4 days at 4°C and 1.2 days at 26°C. Catalase in permeabilized cells was more stable against self-inactivation during catalysis than the enzyme
in cell-free extract and purified catalase. Catalase of CTAB-permeabilized cells was effective in removing the residual H2O2 from H2O2-treated fresh milk:heat pasteurized milk.