FIG. 5.

A. nidulans contains at least four different catalases. Protein extracts (40 μg) prepared from strains CLK20 (catA⁻ catB⁻) and CLK36 (catA⁻ catB⁻ catC⁻) grown for 12, 24 and 48 h were fractionated in a native polyacrylamide gel that was stained to detect catalase activity. A protein sample from isolated conidia (strain FGSC26) is shown as a catalase A and B reference. Numbers below the zymogram are catalase-specific activities (in units per milligram of protein per milliliter) in each sample, measured by O₂ evolution (11). Data are the averages of two determinations, with a maximum variation of 13% with respect to the average.