GLCE epimerises more GlcA to IdoA as sulfate content rises

Stable Identifier
Reaction [transition]
Homo sapiens
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As the sulfate content rises, so does the iduronic acid:glucuronic acid ratio. Once glucosamine is sulfated, glucuronic acid (GlcA) is epimerised to iduronic acid (IdoA). The enzyme glucuronyl C5-epimerase (GLCE) mediates this reaction, evidence of function and cellular location coming from mouse studies (Li et al. 2001, Crawford et al. 2001). The distinction between HS and heparin is fairly arbritary but generally, low-sulfated and GlcA-rich polysaccharides are called HS and high-sulfated and IdoA-rich polysaccharides are called heparin. It can be argued that this structure can now be called either heparan sulfate-PG or heparin-PG.

Literature References
PubMed ID Title Journal Year
11274177 Characterization of the D-glucuronyl C5-epimerase involved in the biosynthesis of heparin and heparan sulfate

Li, JP, Gong, F, Jalkanen, M, Lindahl, U, El Darwish, K

J Biol Chem 2001
11279150 Cloning, Golgi localization, and enzyme activity of the full-length heparin/heparan sulfate-glucuronic acid C5-epimerase

Crawford, BE, Pinhal, MA, Esko, JD, Olson, SK

J Biol Chem 2001
Event Information
Catalyst Activity

heparosan-N-sulfate-glucuronate 5-epimerase activity of GLCE [Golgi membrane]

Inferred From
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