FIG. 3.

Efficacies of phytate-phosphorus hydrolysis in soybean meal by the single mutant E228K and the triple mutant E228K-K300R-K301E at pH 2.5 (0.2 M glycine-HCl), 3.5 (0.2 M glycine-HCl), and 5.5 (0.2 M citrate) at 37°C compared with that of the WT. The hydrolysis rates were calculated as the percentage of the WT phytase at pH 5.5, and the values are means ± standard errors (n = 3). An asterisk indicates a difference (P < 0.05) between pH 5.5 and other pH values within each enzyme. Different letters indicate differences (P < 0.05) between the WT and the mutants within each pH point.