Pasteurella multocida Heparosan synthase 2 (PmHS2)

Pasteurella multocida Heparosan synthase 2 (PmHS2) Accepted Name Hyaluronan synthase. Alternative Name(s) HAS. Reaction catalysed UDP-alpha-N-acetyl-D-glucosamine  +  beta-D-glucuronosyl-(1->3)-N-acetyl-beta-D-glucosaminyl-(1->4)-(nascent hyaluronan)  <=>  UDP  +  N-acetyl-beta-D-glucosaminyl-(1->4)-beta-D-glucuronosyl-(1->3)-N-acetyl-beta-D-glucosaminyl-(1->4)-(nascent hyaluronan) UDP-alpha-D-glucuronate  +  N-acetyl-beta-D-glucosaminyl-(1->4)-beta-D-glucuronosyl-(1->3)-(nascent hyaluronan)  <=>  UDP  +  beta-D-glucuronosyl-(1->3)-N-acetyl-beta-D-glucosaminyl-(1->4)-beta-D-glucuronosyl-(1->3)-(nascent hyaluronan) Cofactor(s) Mg(2+). Comment(s) Adds GlcNAc to nascent hyaluronan when the non-reducing end is GlcA, but it adds GlcA when the non-reducing end is GlcNAc. Highly specific for UDP-GlcNAc and UDP-GlcA; no copolymerization is observed if either is replaced by UDP-Glc, UDP-Gal, UDP-GalNAc or UDP-GalA.