Fig. 3

Optimal pH (a), optimal temperature (b), pH stability (c) and thermostability (d) of the purified Mg-αGlu (dotted lines) and Mr-αGlu (continuous lines). The effect of pH and temperature on the enzymatic activity was assessed on sucrose 60 g/L at 30 °C and pH 7.0, respectively. For enzyme stability profiles, the recombinant proteins were incubated for 30 min (red lines), 60 min (blue lines) and 90 min (green lines) over different pH and temperature ranges prior to the addition of the substrate. Then, remaining activity was evaluated at 30 °C and pH 7.0, as described in the “Methods” sections. Experiments were performed in triplicate and the standard errors are indicated