IntEnz

EC 2.4.1.223 - Glucuronosyl-galactosyl-proteoglycan 4-α-N-acetylglucosaminyltransferase

IntEnz Enzyme Nomenclature
EC 2.4.1.223

Names

Reaction

• 16221 [IUBMB]
  3-O-(β-D-GlcA-(1→3)-β-D-Gal-(1→3)-β-D-Gal-(1→4)-β-D-Xyl)-L-seryl-[protein]

  3-O-(beta-D-GlcA-(1->3)-beta-D-Gal-(1->3)-beta-D-Gal-(1->4)-beta-D-Xyl)-L-seryl-[protein]

  GENERIC:12573

  Is ROOT: no
  ROOT compound: GENERIC:9624

  Number of residues: 1

  3-O-(β-D-glucuronosyl-(1→3)-β-D-galactosyl-(1→3)-β-D-galactosyl-(1→4)-β-D-xylosyl)-L-serine residue 3-O-(beta-D-glucuronosyl-(1->3)-beta-D-galactosyl-(1->3)-beta-D-galactosyl-(1->4)-beta-D-xylosyl)-L-serine residue Name origin: UniProt - CHECKED (C) CHEBI:132093 Formula: C26H40NO22 Charge: -1 Position: undefined ChEBI compound status: CHECKED (C)

  +

  UDP-N-acetyl-α-D-glucosamine

  UDP-N-acetyl-alpha-D-glucosamine

  Name origin: UniProt - CHECKED (C)

  CHEBI:57705

  Formula: C17H25N3O17P2
  Charge: -2

  ChEBI compound status: CHECKED (C)

  

  =

  3-O-(α-D-GlcNAc-(1→4)-β-D-GlcA-(1→3)-β-D-Gal-(1→3)-β-D-Gal-(1→4)-β-D-Xyl)-L-seryl-[protein]

  3-O-(alpha-D-GlcNAc-(1->4)-beta-D-GlcA-(1->3)-beta-D-Gal-(1->3)-beta-D-Gal-(1->4)-beta-D-Xyl)-L-seryl-[protein]

  GENERIC:12574

  Is ROOT: no
  ROOT compound: GENERIC:9624

  Number of residues: 1

  3-O-(N-acetyl-α-D-glucosaminyl-(1→4)-β-D-glucuronosyl-(1→3)-β-D-galactosyl-(1→3)-β-D-galactosyl-(1→4)-β-D-xylosyl)-L-serine residue 3-O-(N-acetyl-alpha-D-glucosaminyl-(1->4)-beta-D-glucuronosyl-(1->3)-beta-D-galactosyl-(1->3)-beta-D-galactosyl-(1->4)-beta-D-xylosyl)-L-serine residue Name origin: UniProt - CHECKED (C) CHEBI:132104 Formula: C34H53N2O27 Charge: -1 Position: undefined ChEBI compound status: CHECKED (C)

  +

  H⁺

  H(+)

  Name origin: UniProt - CHECKED (C)

  CHEBI:15378

  Formula: H
  Charge: 1

  ChEBI compound status: CHECKED (C)

  

  +

  UDP

  UDP

  Name origin: UniProt - CHECKED (C)

  CHEBI:58223

  Formula: C9H11N2O12P2
  Charge: -3

  ChEBI compound status: CHECKED (C)

  

Comments:

Enzyme involved in the initiation of heparin and heparan sulfate synthesis, transferring GlcNAc to the (GlcA-Gal-Gal-Xyl-)Ser core. Apparently products of both the human EXTL2 and EXTL3 genes can catalyse this reaction. In Caenorhabditis elegans, the product of the rib-2 gene displays this activity as well as that of EC 2.4.1.224, glucuronosyl-N-acetylglucosaminyl-proteoglycan 4-α-N-acetylglucosaminyltransferase. For explanation of the use of a superscript in the systematic name, see 2-Carb-37.2.

Links to other databases

References

1. Kitagawa, H., Shimakawa, H. and Sugahara, K.
   The tumor suppressor EXT-like gene EXTL2 encodes an α1,4-N-acetylhexosaminyltransferase that transfers N-acetylgalactosamine and N-acetylglucosamine to the common glycosaminoglycan-protein linkage region. The key enzyme for the chain initiation of heparan sulfate.
   J. Biol. Chem. 274: 13933-13937 (1999). [PMID: 10318803]
2. Kitagawa, H., Egusa, N., Tamura, J.I., Kusche-Gullberg, M., Lindahl, U. and Sugahara, K.
   rib-2, a Caenorhabditis elegans homolog of the human tumor suppressor EXT genes encodes a novel α1,4-N-acetylglucosaminyltransferase involved in the biosynthetic initiation and elongation of heparan sulfate.
   J. Biol. Chem. 276: 4834-4838 (2001). [PMID: 11121397]

[EC 2.4.1.223 created 2002, modified 2016]