Glycogen debranching enzyme 2940689 171266394 2007-11-13T19:46:11Z Alaibot 1324179 Robot: sorting stub (based on existing categorisation) {{protein |Name=amylo-1, 6-glucosidase, 4-alpha-glucanotransferase (glycogen debranching enzyme, glycogen storage disease type III) |caption= |image= |width= |HGNCid=321 |Symbol=AGL |AltSymbols= |EntrezGene=178 |OMIM=232400 |RefSeq=NM_000028 |UniProt=P35573 |PDB= |ECnumber=2.4.1.25 |Chromosome=1 |Arm=p |Band=21 |LocusSupplementaryData= }} A '''debranching enzyme''' is a molecule that helps facilitate the breakdown of [[glycogen]]. ==Function== Debranching enzymes work by first transferring three [[glucose]] subunits of glycogen from one parallel chain to another. This shortens one linear branch while lengthening another. Afterwards, the donator branch will contain only one glucose [[residue]] with alpha-1,6 linkage. This remaining residue is in turn cut by the alpha-1,6 glucosidase activity of the debranching enzyme, and attached to the remaining linear branch. This two step process is the general mechanism by which the debranching enzyme "straightens out" glycogen into an unbranched glucose [[polymer]]. These enzymes are important in [[glycogenolysis]] because the cutting enzyme, [[glycogen phosphorylase]], cannot cut a non-linear (or branched) glycogen chain. ==Enzyme classification== The two debranching enzymes are: * 4-α-D-glucanotransferase ({{EC number|2.4.1.25}}) - [[glucosyltransferase]] * amylo-α-1,6-glucosidase ({{EC number|3.2.1.33}}) - [[glucosidase]] ==Pathology== Deficiency in either of these enzymes will result in [[Glycogen storage disease type III]]. ==External links== * {{MeshName|Glycogen+debranching+enzyme}} {{transferase-stub}} {{Glycogenolysis}} {{Glycosyltransferases}} {{Sugar hydrolases}} [[Category:EC 2.4.1]] [[Category:Transferases]]