chondroitin B lyase EC#: 4.2.2.19; ChemWhat Code: 1382527
Product Name
chondroitin B lyase
Example Structure
Synonyms
ChnB, ChonB, chondroitin B lyase, chondroitinase B, CslB, lyase, chondroitin B
EC Number
4.2.2.19
CAS Registry Number
52227-83-5
Comments
This is the only lyase that is known to be specific for dermatan sulfate as substrate. The minimum substrate length required for catalysis is a tetrasaccharide [2]. 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(¦Â1-3)GalNAc(¦Â1-]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(¦Á1-3)GalNAc(¦Â1-]n?of DS. Both the concentrations and locations of sulfate-ester substituents vary with glucosaminoglycan source [5].
Cofactor
History
Reactions
Eliminative cleavage of dermatan sulfate containing (1->4)-beta-D- hexosaminyl and (1->3)-beta-D-glucurosonyl or (1->3)-alpha-L-iduronosyl linkages to disaccharides containing 4-deoxy-beta-D-gluc-4-enuronosyl groups to yield a 4,5-unsaturated dermatan-sulfate disaccharide (Delta- UA-GalNAc-4S).
