An enzyme showing pullulanase activity has been purified from sweet corn, and separated on hydroxylapatite into what appear to be two isoenzyme forms. The specificities of the two fractions are identical. Pullulan, α-limit dextrins and amylopectin β-limit dextrin are rapidly hydrolyzed by the enzyme; amylopectin is slowly debranched, but there is no significant action on glycogen unless the enzyme is allowed to act simultaneously with β-amylase. The enzyme therefore resembles pullulanase [bacterial R-enzyme, EC 22.214.171.124] from Aerobacter aerogenes. The in vivo significance of this enzyme is discussed.
ASJC Scopus subject areas
- Molecular Biology