ID 3.2.1.179 DE gellan tetrasaccharide unsaturated glucuronosyl hydrolase. AN gellan tetrasaccharide unsaturated glucuronyl hydrolase. AN unsaturated glucuronyl hydrolase. CA beta-D-Delta(4)-GlcA-(1->4)-beta-D-Glc-(1->4)-alpha-L-Rha-(1->3)-D-Glc + CA H2O = 5-dehydro-4-deoxy-D-glucuronate + beta-D-Glc-(1->4)-alpha-L-Rha- CA (1->3)-D-Glc. CC -!- The enzyme releases 4-deoxy-4(5)-unsaturated D-glucuronic acid from CC oligosaccharides produced by polysaccharide lyases, e.g. the CC tetrasaccharide beta-D-4-deoxy-Delta(4)-GlcAp-(1->4)-beta-D-Glcp- CC (1->4)-alpha-L-Rhap-(1->3)-D-Glcp produced by EC 4.2.2.25. CC -!- The enzyme can also hydrolyze unsaturated chondroitin and hyaluronate CC disaccharides (beta-D-4-deoxy-Delta(4)-GlcAp-(1->3)-beta-D-GalNAc, CC beta-D-4-deoxy-Delta(4)-GlcAp-(1->3)-beta-D-GalNAc6S, beta-D-4-deoxy- CC Delta(4)-GlcAp2S-(1->3)-beta-D-GalNAc, beta-D-4-deoxy-Delta(4)-GlcAp- CC (1->3)-beta-D-GlcNAc), preferring the unsulfated disaccharides to the CC sulfated disaccharides. DR Q9RC92, UGL_BACGL ; //