Reaction: The addition of GalNAc to the terminal glucuronate residue forms chondroitin

- in pathway: Chondroitin sulfate biosynthesis
Chondroitin sulfate N-acetylgalactosaminyltransferases 1 and 2 (CSGALNACT1 and 2) (Uyama et al. 2002, Gotoh et al. 2002) transfer N-acetylgalactosamine (GalNAc) from UDP-GalNAc to the glucuronate (GlcA) residue of the linker sequence. This first addition to the linker determines this GAG to be chondroitin. Chondroitin is comprised of the repeating disaccharide unit GalNAc-GlcA.
Reaction - small molecule participants:
UDP [Golgi lumen]
UDP-GalNAc [Golgi lumen]
Reactome.org reaction link: R-HSA-1971482

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Reaction input - small molecules:
UDP-N-acetyl-D-galactosamine(2-)
ChEBI:57847
Reaction output - small molecules:
UDP(3-)
ChEBI:58223
Reactome.org link: R-HSA-1971482