InterPro domain: IPR037439

This entry consists of glycogen branching enzyme GlgB from bacteria and GBE1 from eukaryotes, which are responsible for the transfer of chains of alpha(1,4)-linked glucosyl residues to other similar chains (in new alpha-(1,6) linkages) in the biosynthesis of glycogen [ 1 ]. GlgB is responsible for the degree of alpha(1,6) branch linkages found in polysaccharides [ 2 ]. GBE1 is required for normal glycogen accumulation in animals [ 3 , 4 ]. Deficiency in GBE1 results in glycogen storage disease type IV [ 5 ].

1. Maize branching enzyme catalyzes synthesis of glycogen-like polysaccharide in glgB-deficient Escherichia coli. Proc. Natl. Acad. Sci. U.S.A. 92, 964-7
2. The degree of branching in (alpha 1,4)-(alpha 1,6)-linked glucopolysaccharides is dependent on intrinsic properties of the branching enzymes. Eur. J. Biochem. 168, 393-7
3. Isolation of human glycogen branching enzyme cDNAs by screening complementation in yeast. J. Biol. Chem. 268, 7509-13
4. Structural basis of glycogen branching enzyme deficiency and pharmacologic rescue by rational peptide design. Hum. Mol. Genet. 24, 5667-76
5. Hepatic and neuromuscular forms of glycogen storage disease type IV caused by mutations in the same glycogen-branching enzyme gene. J. Clin. Invest. 97, 941-8