Fig. 3.
Enzymatic activities of Ser and Trp catalase alleles. (A) Effect of pH on catalase enzymatic activity in ovary homogenates from S (Ser allele) and G3 (Trp allele) females, normalized for total protein in the extract. Means are plotted ± SE. Ser allele, filled circles; Trp allele, open circles. (B) Effect of pH on enzymatic activity of purified recombinant Ser and Trp catalase isoforms. (C) Effect of temperature on enzymatic activity of purified recombinant Ser and Trp catalase isoforms. (D) Effect of substrate concentration on initial velocity of catalysis and determination of Km and Vmax of purified recombinant Ser and Trp catalase isoforms. (E) Native gel electrophoresis of recombinant Ser and Trp isoforms, showing that the Trp isoform has relatively less protein in tetramer form. (F) SDS/PAGE of Ser and Trp recombinant protein isoforms shows a single band.