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Your query returned 3 entries. Printable version
EC | 4.2.2.5 | ||||||||||||
Accepted name: | chondroitin AC lyase | ||||||||||||
Reaction: | Eliminative degradation of polysaccharides containing 1,4-β-D-hexosaminyl and 1,3-β-D-glucuronosyl linkages to disaccharides containing 4-deoxy-β-D-gluc-4-enuronosyl groups | ||||||||||||
Glossary: | chondroitin sulfate A = chondroitin 4-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 sulfate lyase; chondroitin AC eliminase; chondroitinase AC; ChnAC | ||||||||||||
Systematic name: | chondroitin AC lyase | ||||||||||||
Comments: | Acts on chondroitin 4-sulfate and chondroitin 6-sulfate, but less well on hyaluronate. 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 [4]. | ||||||||||||
Links to other databases: | BRENDA, EXPASY, KEGG, MetaCyc, PDB, CAS registry number: 9047-57-8 | ||||||||||||
References: |
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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, KEGG, MetaCyc, PDB, CAS registry number: 9024-13-9 | ||||||||||||
References: |
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EC | 4.2.2.21 | ||||||||||||
Accepted name: | chondroitin-sulfate-ABC exolyase | ||||||||||||
Reaction: | Exolytic removal of Δ4-unsaturated disaccharide residues from the non-reducing ends of both polymeric chondroitin/dermatan sulfates and their oligosaccharide fragments. | ||||||||||||
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 exoeliminase; chondroitin sulfate ABC exolyase; ChS ABC lyase II | ||||||||||||
Systematic name: | chondroitin-sulfate-ABC exolyase | ||||||||||||
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. The related enzyme EC 4.2.2.20, chondroitin-sulfate-ABC endolyase, has the same substrate specificity but produces a mixture of oligosaccharides of different sizes that are ultimately degraded to tetra- and disaccharides [4]. Both enzymes act by the removal of a relatively acidic C-5 proton of the uronic acid followed by the elimination of a 4-linked hexosamine, resulting in the formation of an unsaturated C4—C5 bond on the hexuronic acid moiety of the products [4,6]. | ||||||||||||
Links to other databases: | BRENDA, EXPASY, KEGG, MetaCyc, PDB, CAS registry number: 1000607-06-6 | ||||||||||||
References: |
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