Reaction: ST3GAL1-6 transfer Neu5Ac to terminal Gal (alpha-2,3 link)

- in pathway: Sialic acid metabolism
The alpha-2,3-sialyltransferases 1-6 (ST3GAL1-6) are able to transfer a sialic acid (Neu5Ac) moiety to the terminal galactosyl (Gal-R) residue of O-glycosylated proteins and some gangliosides. Neu5Ac is added to Gal-R via an alpha-2,3 linkage (Shang et al. 1999, Kim et al. 1996, Kitagawa & Paulson 1993, Basu et al. 1993, Ishii et al. 1998, Okajima et al. 1999). Once sialylated, glycoconjugates translocate to the plasma membrane by an unknown mechanism. For simplicity, Gal is shown in a generic form where R represents other sugars O-linked to proteins which can result in a large variability in glycoconjugate structures.
Reaction - small molecule participants:
Neu5Ac-2,3-Gal-R [Golgi lumen]
CMP [Golgi lumen]
CMP-Neu5Ac [Golgi lumen]
Gal-R [Golgi lumen]
Reactome.org reaction link: R-HSA-4084984

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Reaction input - small molecules:
CMP-N-acetyl-beta-neuraminate(2-)
ChEBI:57812
alpha-D-galactosyl group
ChEBI:61248
Reaction output - small molecules:
alpha-N-acetylneuraminyl-(2->3)-D-galactosyl group
ChEBI:75127
cytidine 5'-monophosphate(2-)
ChEBI:60377
Reactome.org link: R-HSA-4084984