Figure 4.

Debranching kinetics of maize amylopectin by wild-type and mutant enzymes. Semipurified isoamylases were incubated in the presence of 5 mg mL⁻¹ of maize amylopectin (see “Materials and Methods”). Aliquots were boiled after 10, 30, 60, and 120 min and chain length distributions were analyzed through HPAED-PAD. A, Chain length distribution of glucans liberated by wild-type semipurified isoamylase. B, Chain length distribution of glucans liberated by semipurified isoamylase from the sta8 defective strain. The results are displayed as percentages of chains of DP between 1 to 32. The x scale displays a DP scale, and the y axis represents the relative frequencies of the chains expressed as percentages.