D Man alpha (1 3) D Glc beta (1 4) D Glc alpha 1 diphosphoundecaprenol 2 beta glucuronyltransferase

D-Man-alpha-(1->3)-D-Glc-beta-(1->4)-D-Glc-alpha-1-diphosphoundecaprenol 2-beta-glucuronyltransferase (EC 2.4.1.264, GumK) is an enzyme with systematic name UDP-glucuronate:D-Man-alpha-(1->3)-D-Glc-beta-(1->4)-D-Glc-alpha-1-diphospho-ditrans,octacis-undecaprenol beta-1,2-glucuronyltransferase. This enzyme catalyses the following chemical reaction

UDP-glucuronate + D-Man-alpha-(1->3)-D-Glc-beta-(1->4)-D-Glc-alpha-1-diphospho-ditrans,octacis-undecaprenol ⇌ UDP + D-GlcA-beta-(1->2)-D-Man-alpha-(1->3)-D-Glc-beta-(1->4)-D-Glc-alpha-1-diphospho-ditrans,octacis-undecaprenol

The enzyme is involved in the biosynthesis of the exopolysaccharides xanthan (in the bacterium Xanthomonas campestris) and acetan (in the bacterium Gluconacetobacter xylinus).