2.4.1.231 5.5 6.8 pH 5.5: about 80% of maximal activity, pH 75% of maximal activity, synthesis of alpha,alpha-trehalose 674984 2.4.1.231 5.5 7.8 pH 5.5: about 75% of maximal activity, pH 7.8: about 80% of maxuimal activity, phosphorolysis 674984 2.4.1.231 6.2 6.6 decrease in enzyme activity below pH 6.2 and above pH 6.6 644898