Figure 9.

Activities of Isoamylase-Type DBEs from Various Sources toward Amylopectin and Phytoglycogen.

Enzymatic activities were determined by measuring the amounts of malto-oligosaccharides liberated after the enzymatic reactions with amylopectin (blue bars) or phytoglycogen (brown bars) as glucan substrate, as described in the Methods. The enzymes measured were Os-ISA1, rice ISA1; Os-ISA3, rice ISA3; Ce-ISA, Cyanothece ATCC51142 DBE; Se-DBE, S. elongatus PCC7942 DBE; and Ec-GlgX, E. coli GlgX. Vertical axis presents the debranching activity as expressed by nmol equivalents liberated/μg protein/min, except that the activities of Os-ISA1 were reduced to 0.025 as a result of to their much higher activities compared with other enzymes. Each value represents the mean ± sd of three separate measurements.