Glycogen Debranching Enzyme
| Glycogen Debranching Enzyme (4-α-Glucanotransferase) | ||
|---|---|---|
| Properties of human protein | ||
| Mass / length primary structure | 1532 amino acids | |
| Secondary to quaternary structure | Monomer | |
| Isoforms | 6th | |
| Identifier | ||
| Gene name | AGL | |
| External IDs | ||
| Enzyme classification | ||
| EC, category | 2.4.1.25 , glycosyl transferase | |
| Response type | Transfer of short polysaccharide chains | |
| Substrate | Glycogen with long side chains | |
| Products | Short side chain glycogen (a residue of glucose) | |
| EC, category | 3.2.1.33 , glycosidase | |
| Response type | Splitting off of a glucose residue | |
| Substrate | Glycogen with 1,6-glucose residue | |
| Products | linear dextrin | |
| Orthologue | ||
| human | House mouse | |
| Entrez | 178 | 77559 |
| Ensemble | ENSG00000162688 | ENSMUSG00000033400 |
| UniProt | P35573 | E0CX86 |
| Refseq (mRNA) | NM_000028 | NM_001081326 |
| Refseq (protein) | NP_000019 | NP_001074795 |
| Gene locus | Chr 1: 99.85 - 99.92 Mb | Chr 3: 116.74 - 116.81 Mb |
| PubMed search | 178 |
77559
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Glycogen debranching enzyme ( gene : AGL ) is the name of the enzyme that breaks down branches in glycogen . The breakdown of these branches is a partial step in the utilization of the reserve substance glycogen in the context of glycogenolysis . The enzyme is found in mammals and fungi .
The enzyme is multifunctional ; it itself consists of two enzymes that catalyze two sub-steps of the reaction : 4-α-glucanotransferase and amylo-α-1,6-glucosidase . There are at least six isoforms in humans that are found in different tissue types. Mutations in the AGL gene can lead to type III glycogen storage disease ( Cori disease ).
Catalyzed reactions
First of all, the 4-α-glucanotransferase ( EC 2.4.1.25 ) transfers one side chain to another side chain except for a single glucose residue.
+ H 2 O + α-D-glucose
Then the individual glucose residue is hydrolyzed by amylo-α-1,6-glucosidase ( EC 3.2.1.33 ) . The process starts over until all side chains are broken down and there is linear dextrin .
