MGAM
Description
The MGAM (maltase-glucoamylase) is a protein-coding gene located on chromosome 7.
Maltase-glucoamylase, intestinal is an enzyme that in humans is encoded by the MGAM gene. Maltase-glucoamylase is an alpha-glucosidase digestive enzyme. It consists of two subunits with differing substrate specificity. Recombinant enzyme studies have shown that its N-terminal catalytic domain has highest activity against maltose, while the C-terminal domain has a broader substrate specificity and activity against glucose oligomers. In the small intestine, this enzyme works in synergy with sucrase-isomaltase and alpha-amylase to digest the full range of dietary starches.
== Gene == The MGAM gene –– which is located on chromosome 7q34 –– codes for the protein Maltase-Glucoamylase. An alternative name for Maltase-Glucoamylase is glucan 1,4-alpha-glycosidase.
== Tissue distribution == Maltase-glucoamylase is a membrane-bound enzyme located in the intestinal walls. This lining of the intestine forms brush border in which food has to pass in order for the intestines to absorb the food.
== Enzymatic mechanism == This enzyme is a part of a family of enzymes called glycoside hydrolase family 31 (GH31).
Alpha-(1,4) exo-glucosidase involved in the breakdown of dietary starch oligosaccharides in the small intestine. Cleaves the non-reducing alpha-(1,4)-linked glucose residue in linear dextrins with retention of anomeric center stereochemistry. Mainly hydrolyzes short length oligomaltoses having two to seven glucose residues. Can cleave alpha-(1,2), alpha-(1,3) and alpha-(1,6) glycosidic linkages with lower efficiency, whereas beta glycosidic linkages are usually not hydrolyzed.
MGAM is also known as MG, MGA.
