Figure 4
Comparison of the effects of signal peptides on glucoamylase activity during the course of growth. WT and the transformants XH61-5 and XH86-8 were compared in the one-step (A) and two-step (B) processes using liquefied corn starch as the carbon source. Cultures were sampled every 12 h. The activity of expressed secreted glucoamylase was assayed at 40°C and pH4.6 using soluble starch as the substrate. Specific activity was defined as one unit of enzyme activity per ml of crude culture filtrates.