EC - Mannosyl-oligosaccharide glucosidase

  IntEnz view ENZYME view

IntEnz Enzyme Nomenclature


Accepted name:
mannosyl-oligosaccharide glucosidase
Other names:
Glc3Man9NAc2 oligosaccharide glucosidase
trimming glucosidase I
processing A-glucosidase I
CWH41 (gene name)
MOGS (gene name)
mannosyl-oligosaccharide glucohydrolase
Systematic name:
Glc3Man9GlcNAc2-[protein] glucohydrolase (configuration-inverting)



This enzyme catalyses the first step in the processing of the N-glycan tetradecasaccharide precursor Glc3Man9GlcNAc2, which takes place in the endoplasmic reticulum, by removing the distal α-1,2-linked glucose residue. This and subsequent processing steps are required before complex N-glycans can be synthesized.

Links to other databases

Enzymes and pathways: NC-IUBMB , BRENDA , ExplorEnz , ENZYME@ExPASy , KEGG , MetaCyc , UniPathway
Structural data: CSA , EC2PDB
Gene Ontology: GO:0004573


  1. Elting, J.J., Chen, W.W. and Lennarz, J.
    Characterization of a glucosidase involved in an initial step in the processing of oligosaccharide chains.
    J. Biol. Chem. 255: 2325-2331 (1980). [PMID: 7358674]
  2. Grinna, L.S. and Robbins, P.W.
    Glycoprotein biosynthesis. Rat liver microsomal glucosidases which process oligosaccharides.
    J. Biol. Chem. 254: 8814-8818 (1979). [PMID: 479161]
  3. Kilker, R.D., Saunier, B., Tkacz, J.S. and Herscovics, A.
    Partial purification from Saccharomyces cerevisiae of a soluble glucosidase which removes the terminal glucose from the oligosaccharide Glc3Man9GlcNAc2.
    J. Biol. Chem. 256: 5299-5603 (1981). [PMID: 7014569]
  4. Grinna, L.S. and Robbins, P.W.
    Substrate specificities of rat liver microsomal glucosidases which process glycoproteins.
    J. Biol. Chem. 255: 2255-2258 (1980). [PMID: 7358666]
  5. Mark, M.J. and Kornfeld, S.
    Partial purification and characterization of the glucosidases involved in the processing of asparagine-linked oligosaccharides.
    Arch. Biochem. Biophys. 199: 249-258 (1980). [PMID: 7356331]

[EC created 1984, modified 2018]