FIGURE 5.

Effect of pH on AtAMY3 and HvAMY1 activity. The enzyme activity of AtAMY3 (A, 10 μg) and HvAMY1 (B, 10 ng) was assayed in Britton-Robinson buffer under the standard assay conditions, where pH of the mixture was titrated as indicated (pH 5–8.5). The reactions were stopped after 60 min for AtAMY3 and 20 min for HvAMY1. Values represent the mean ± S.E. (n = 3). Error bars not visible are smaller than the symbols. Note the difference in the y axis scale between A and B. PNP, para-nitrophenol.