Synonyms |
C5 uronosyl epimerase, C5-epi, C5-epimerase, D-Glucuronyl C-5 epimerase, D-glucuronyl C5-epimerase, Epimerase, polyglucuronate, Glce, GlceA, GlceB, glucuronosyl C-5 epimerase, glucuronyl C5-epimerase, heparan sulfate C-5 epimerase, Heparan sulfate C5-epimerase, Heparosan N-sulfate D-glucuronosyl 5-epimerase, heparosan-glucuronate 5-epimerase, Heparosan-N-sulfate-D-glucuronosyl-5-epimerase, HG-5epi, HNSG-5epi, HS C5-epimerase, HS glucuronyl C5-epimerase, Hsepi, RED-C5-epimerase |
Comments |
The enzyme acts on?D-glucosyluronate residues in?N-sulfated heparosan polymers, converting them to?L-iduronate, thus modifying the polymer to heparan-N-sulfate. The enzyme requires that at least the?N-acetylglucosamine residue linked to C-4 of the substrate has been deacetylated and?N-sulfated, and activity is highest with fully?N-sulfated substrate. It does not act on glucuronate residues that are?O-sulfated or are adjacent to?N-acetylglucosamine residues that are?O-sulfated at the 6 position. Thus the epimerization from?D-glucuronate to?L-iduronate occurs after?N-sulfation of glucosamine residues but before?O-sulfation. Not identical with EC?5.1.3.19, chondroitin-glucuronate 5-epimerase or with EC?5.1.3.36, heparosan-glucuronate 5-epimerase. |