?cl19188: PL-6 Superfamily (this model, PSSM-Id:418539 is obsolete and has been replaced by 450265)
Polysaccharide Lyase Family 6 Polysaccharide Lyase Family 6 is a family of beta-helical polysaccharide lyases. Members include alginate lyase (EC 4.2.2.3) and chondroitinase B (EC 4.2.2.19). Chondroitinase B is an enzyme that only cleaves the beta-(1,4)-linkage of dermatan sulfate (DS), leading to 4,5-unsaturated dermatan sulfate disaccharides as the product. DS is a highly sulfated, unbranched polysaccharide belonging to a family of glycosaminoglycans (GAGs) composed of alternating hexosamine (gluco- or galactosamine) and uronic acid (D-glucuronic or L-iduronic acid) moieties. DS contains alternating 1,4-beta-D-galactosamine (GalNac) and 1,3-alpha-L-iduronic acid units. The related chondroitin sulfate (CS) contains alternating GalNac and 1,3-beta-D-glucuronic acid units. Alginate lyases (known as either mannuronate (EC 4.2.2.3) or guluronate lyases (EC 4.2.2.11) catalyze the degradation of alginate, a copolymer of alpha-L-guluronate and its C5 epimer beta-D-mannuronate.
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