Maltase glucoamylase
| MGAM | ||
|---|---|---|
| other names |
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Existing structural data : 2QLY , 2QMJ , 3CTT , 3L4T , 3L4U , 3L4V |
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| Properties of human protein | ||
| Mass / length primary structure | 1857 amino acids, 209852 Da | |
| Secondary to quaternary structure | Monomer; single pass type 2 membrane protein | |
| Identifier | ||
| External IDs | ||
| Enzyme classification | ||
| EC, category | 3.2.1.20 , glycosidase | |
| Substrate | terminal 1,4-linked α-D-glucose residues | |
| Products | α-D-glucose | |
| Orthologue | ||
| human | House mouse | |
| Entrez | 8972 | 232714 |
| UniProt | O43451 | |
| PubMed search | 8972 |
232714
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Maltase-glucoamylase (also: α-glucosidase , gene : MGAM ) is the enzyme that causes α- glucose to be split off from glucose chains. It is therefore essential for vertebrates to digest linear-chain carbohydrates . In particular, the breakdown of disaccharides is faster with MGAM than with sucrase isomaltase . In humans, the enzyme is produced on the microvilli of the small intestine , in granulocytes and the kidneys .
The maltase glucoamylase should not be confused with the lysosomal α-glucosidase (also called acid maltase ).
Maltase-glucoamylase and sucrase-isomaltase complement each other in the digestive work. In evolutionary terms, MGAM emerged from a copy of the SI, which itself was created as a double enzyme from the copy of a smaller enzyme. On the other hand, the MGAM of the mouse already has around 3900 amino acids, so a further doubling has already taken place.
α-Glucosidase inhibitors are used as antidiabetic agents for the treatment of type 2 diabetes mellitus . α-glucosidase inhibitors are e.g. B. acarbose and miglitol .
Individual evidence
- ↑ UniProt O43451
- ↑ HomoloGene to Maltase-Glucoamylase
- ↑ Nichols BL, Avery S, Sen P, Swallow DM, Hahn D, Sterchi E: The maltase-glucoamylase gene: common ancestry to sucrase-isomaltase with complementary starch digestion activities . In: Proc. Natl. Acad. Sci. USA . 100, No. 3, February 2003, pp. 1432-7. doi : 10.1073 / pnas.0237170100 . PMID 12547908 . PMC 298790 (free full text).
