Maltase-glucoamylase

Maltase-glucoamylase
PDB rendering based on 2qly.
Available structures PDB Ortholog search: PDBe, RCSB List of PDB id codes 2QLY​, 2QMJ​, 3CTT​, 3L4T​, 3L4U​, 3L4V​, 3L4W​, 3L4X​, 3L4Y​, 3L4Z​, 3TON​, 3TOP​
Identifiers
Symbols	MGAM ; MG; MGA
External IDs	OMIM: 154360 MGI: 1203495 HomoloGene: 130099 IUPHAR: 2627 ChEMBL: 2074 GeneCards: MGAM Gene
EC number	3.2.1.20, 3.2.1.3
Gene ontology Molecular function • catalytic activity • glucan 1,4-alpha-glucosidase activity • alpha-1,4-glucosidase activity • amylase activity • carbohydrate binding • maltose alpha-glucosidase activity Cellular component • plasma membrane • integral component of membrane • apical plasma membrane • extracellular exosome Biological process • maltose metabolic process • carbohydrate metabolic process • starch catabolic process • polysaccharide digestion • small molecule metabolic process Sources: Amigo / QuickGO
Orthologs
Species	Human	Mouse
Entrez	8972	232714
Ensembl	ENSG00000257335	ENSMUSG00000068587
UniProt	O43451	B5THE2
RefSeq (mRNA)	NM_004668	NM_001171003
RefSeq (protein)	NP_004659	NP_001164474
Location (UCSC)	Chr 7: 141.91 – 142.11 Mb	Chr 6: 40.63 – 40.77 Mb
PubMed search

Maltase-glucoamylase, intestinal is an enzyme that in humans is encoded by the MGAM gene.^[1][2]

Maltase-glucoamylase is 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.^[3] In the small intestine, this enzyme works in synergy with sucrase-isomaltase and alpha-amylase to digest the full range of dietary starches.

See also

• Alpha-glucosidase
• Maltase

References

1. "Entrez Gene: maltase-glucoamylase (alpha-glucosidase)".
2. Nichols BL, Eldering J, Avery S, Hahn D, Quaroni A, Sterchi E (January 1998). "Human small intestinal maltase-glucoamylase cDNA cloning. Homology to sucrase-isomaltase". J. Biol. Chem. 273 (5): 3076–81. doi:10.1074/jbc.273.5.3076. PMID 9446624.
3. Quezada-Calvillo R, Sim L, Ao Z, Hamaker BR, Quaroni A, Brayer GD, Sterchi EE, Robayo-Torres CC, Rose DR, Nichols BL (2008). "Luminal starch substrate "brake" on maltase-glucoamylase activity is located within the glucoamylase subunit". J. Nutr. 138 (4): 685–92. PMID 18356321.

Further reading

• Nichols BL, Avery S, Sen P, et al. (2003). "The maltase-glucoamylase gene: common ancestry to sucrase-isomaltase with complementary starch digestion activities.". Proc. Natl. Acad. Sci. U.S.A. 100 (3): 1432–7. doi:10.1073/pnas.0237170100. PMC 298790. PMID 12547908.
• Takeshita F, Ishii KJ, Kobiyama K, et al. (2005). "TRAF4 acts as a silencer in TLR-mediated signaling through the association with TRAF6 and TRIF.". Eur. J. Immunol. 35 (8): 2477–85. doi:10.1002/eji.200526151. PMID 16052631.
• Hillier LW, Fulton RS, Fulton LA, et al. (2003). "The DNA sequence of human chromosome 7.". Nature 424 (6945): 157–64. doi:10.1038/nature01782. PMID 12853948.
• Danielsen EM (1987). "Tyrosine sulfation, a post-translational modification of microvillar enzymes in the small intestinal enterocyte.". EMBO J. 6 (10): 2891–6. PMC 553723. PMID 3121301.
• Korpela MP, Paetau A, Löfberg MI, et al. (2009). "A novel mutation of the GAA gene in a Finnish late-onset Pompe disease patient: clinical phenotype and follow-up with enzyme replacement therapy.". Muscle Nerve 40 (1): 143–8. doi:10.1002/mus.21291. PMID 19472353.
• Sim L, Quezada-Calvillo R, Sterchi EE, et al. (2008). "Human intestinal maltase-glucoamylase: crystal structure of the N-terminal catalytic subunit and basis of inhibition and substrate specificity.". J. Mol. Biol. 375 (3): 782–92. doi:10.1016/j.jmb.2007.10.069. PMID 18036614.
• Strausberg RL, Feingold EA, Grouse LH, et al. (2002). "Generation and initial analysis of more than 15,000 full-length human and mouse cDNA sequences.". Proc. Natl. Acad. Sci. U.S.A. 99 (26): 16899–903. doi:10.1073/pnas.242603899. PMC 139241. PMID 12477932.
• Naim HY, Sterchi EE, Lentze MJ (1988). "Structure, biosynthesis, and glycosylation of human small intestinal maltase-glucoamylase.". J. Biol. Chem. 263 (36): 19709–17. PMID 3143729.
• Ao Z, Quezada-Calvillo R, Sim L, et al. (2007). "Evidence of native starch degradation with human small intestinal maltase-glucoamylase (recombinant).". FEBS Lett. 581 (13): 2381–8. doi:10.1016/j.febslet.2007.04.035. PMID 17485087.
• Tuğrul S, Kutlu T, Pekin O, et al. (2008). "Clinical, endocrine, and metabolic effects of acarbose, an alpha-glucosidase inhibitor, in overweight and nonoverweight patients with polycystic ovarian syndrome.". Fertil. Steril. 90 (4): 1144–8. doi:10.1016/j.fertnstert.2007.07.1326. PMID 18377903.