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Your query returned 1 entry. Printable version
EC | 4.2.2.20 | ||||||||||
Accepted name: | chondroitin-sulfate-ABC endolyase | ||||||||||
Reaction: | Endolytic cleavage of (1→4)-β-galactosaminic bonds between N-acetylgalactosamine and either D-glucuronic acid or L-iduronic acid to produce a mixture of Δ4-unsaturated oligosaccharides of different sizes that are ultimately degraded to Δ4-unsaturated tetra- and disaccharides | ||||||||||
For diagram of reaction click here | |||||||||||
Glossary: | chondroitin sulfate A = chondroitin 4-sulfate chondroitin sulfate B = dermatan sulfate chondroitin sulfate C = chondroitin 6-sulfate For the nomenclature of glycoproteins, glycopeptides and peptidoglycans, click here |
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Other name(s): | chondroitinase (ambiguous); chondroitin ABC eliminase (ambiguous); chondroitinase ABC (ambiguous); chondroitin ABC lyase (ambiguous); chondroitin sulfate ABC lyase (ambiguous); ChS ABC lyase (ambiguous); chondroitin sulfate ABC endoeliminase; chondroitin sulfate ABC endolyase; ChS ABC lyase I | ||||||||||
Systematic name: | chondroitin-sulfate-ABC endolyase | ||||||||||
Comments: | This enzyme degrades a variety of glycosaminoglycans of the chondroitin-sulfate- and dermatan-sulfate type. Chondroitin sulfate, chondroitin-sulfate proteoglycan and dermatan sulfate are the best substrates but the enzyme can also act on hyaluronan at a much lower rate. Keratan sulfate, heparan sulfate and heparin are not substrates. In general, chondroitin sulfate (CS) and dermatan sulfate (DS) chains comprise a linkage region, a chain cap and a repeat region. The repeat region of CS is a repeating disaccharide of glucuronic acid (GlcA) and N-acetylgalactosamine (GalNAc) [-4)GlcA(β1-3)GalNAc(β1-]n, which may be O-sulfated on the C-4 and/or C-6 of GalNAc and C-2 of GlcA. GlcA residues of CS may be epimerized to iduronic acid (IdoA) forming the repeating disaccharide [-4)IdoA(α1-3)GalNAc(β1-]n of DS. Both the concentrations and locations of sulfate-ester substituents vary with glucosaminoglycan source [5]. The related enzyme EC 4.2.2.21, chondroitin-sulfate-ABC exolyase, has the same substrate specificity but removes disaccharide residues from the non-reducing ends of both polymeric chondroitin sulfates and their oligosaccharide fragments produced by EC 4.2.2.20 [4]. | ||||||||||
Links to other databases: | BRENDA, EXPASY, Gene, KEGG, MetaCyc, PDB, CAS registry number: 9024-13-9 | ||||||||||
References: |
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