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 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
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:
1. Yamagata, T., Saito, H., Habuchi, O. and Suzuki, S. Purification and properties of bacterial chondroitinases and chondrosulfatases. J. Biol. Chem. 243 (1968) 1523-1535. [PMID: 5647268]
2. Saito, H., Yamagata, T. and Suzuki, S. Enzymatic methods for the determination of small quantities of isomeric chondroitin sulfates. J. Biol. Chem. 243 (1968) 1536-1542. [PMID: 4231029]
3. Suzuki, S., Saito, H., Yamagata, T., Anno, K., Seno, N., Kawai, Y. and Furuhashi, T. Formation of three types of disulfated disaccharides from chondroitin sulfates by chondroitinase digestion. J. Biol. Chem. 243 (1968) 1543-1550. [PMID: 5647269]
4. Hamai, A., Hashimoto, N., Mochizuki, H., Kato, F., Makiguchi, Y., Horie, K. and Suzuki, S. Two distinct chondroitin sulfate ABC lyases. An endoeliminase yielding tetrasaccharides and an exoeliminase preferentially acting on oligosaccharides. J. Biol. Chem. 272 (1997) 9123-9130. [PMID: 9083041]
5. Huckerby, T.N., Nieduszynski, I.A., Giannopoulos, M., Weeks, S.D., Sadler, I.H. and Lauder, R.M. Characterization of oligosaccharides from the chondroitin/dermatan sulfates. 1H-NMR and 13C-NMR studies of reduced trisaccharides and hexasaccharides. FEBS J. 272 (2005) 6276-6286. [PMID: 16336265]