Purification and Characterization of Extracellular Isoamylase from Flavobacterium sp

An extracellular isoamylase from Flavobacterium sp., was purified by fractionation with ammonium sulfate, DEAE‐cellulose, DEAE‐Sephadex A‐50, and CM‐cellulose column chromatography. Single band of the debranching activity of the purified enzyme was detected by polyacrylamide gel electrophoresis. The enzyme efficiently hydrolyzed α‐1,6‐glucosidic linkage of glycogen and amylopectin and formed amylose chains, but did not hydrolyze pullulan. The enzyme released maltotriose from ß‐limit dextrin of waxy maize amylopectin and glycogen, but no detectable maltose and glucose. Action of the isoamylase is similar to other microbial isoamylases but its physical properties are different.