Glycogen debranching enzyme system
1,4-alpha-d-glucan-1,4-alpha-d-glucan 4-alpha-d-glucosyltransferase/dextrin 6 alpha-d-glucanohydrolase. An enzyme system having both 4-alpha-glucanotransferase (ec 220.127.116.11) and amylo-1,6-glucosidase (ec 18.104.22.168) activities. As a transferase it transfers a segment of a 1,4-alpha-d-glucan to a new 4-position in an acceptor, which may be glucose or another 1,4-alpha-d-glucan. As a glucosidase it catalyses the endohydrolysis of 1,6-alpha-d-glucoside linkages at points of branching in chains of 1,4-linked alpha-d-glucose residues. Amylo-1,6-glucosidase activity is deficient in glycogen storage disease type III.