Chondroitin ABC lyase

Effect of chondroitinase ABC. This enzyme (chondroitin ABC lyase, EC A.2.2.A.) also depolymerizes the hyaluronic acid backbone of aggregate. In addition, it can degrade chondroitin sulfate chains of monomer, but not its keratan sulfate chains. 

Various dermatan sulfate derived di-, tetra-, hexa-, octa-, deca- and dodeca-saccharide mixtures have been prepared and purified (on a semi-preparative scale) by controlled depolymerization of dermatan sulfate using chondroitin ABC lyase, The pathways of InsPe hydrolysis by phytase from wheat bran of Triticum aestivum have recently been established. ... 

Deoxy-a-L-tAi o-hex-4-enopyranosyluronic acid-containing disaccharides, formed by the action of chondroitin ABC lyase and chondroitin AC lyase have been determined by a periodate-thiobarbituric acid method. ... 

Chondroitin ABC lyase Chondroitin AC lyase Deoxyribonuclease Dextranase Dextransucrase... 

An improved method for the microdetermination of glycosaminoglycuronans after digestion with chondroitin sulphate lyase ABC and chondroitin sulphate lyase AC has been reported. However, it is based on the already reported... 

Chondroitin ABC and Chondroitin AC Lyases An improved method described for the micro determination of glycosamino-glycans is based on digestion with chondroitin ABC and AC lyases. The method has, however, been published previously. The determination is based on the colour production of 4-deoxy-a-L-t/fr 4-enepyranosyluronic acid-containing disaccharides produced by the action of chondroitin ABC and AC lyases when the periodate-thiobarbituric acid method is applied to the a,j8-unsaturated disaccharides. Suitable conditions for the quantitative assay were described. 

Values for Km and have been determined for the degradation of chondroitin 4- and 6-sulphates, chondroitin 4-sulphate proteoglycan, dermatan sulphate, and hyaluronic acid by a chondroitin sulphate lyase ABC obtained from Proteus vulgaris. The hydrolysis of chondroitin 4-sulphate by the enzyme was inhibited by hyaluronic acid, but not by keratan sulphate. The findings were discussed in connection with the use of chondroitin sulphate lyase ABC as a reagent for the degradation of tissue glycosaminoglycans. 

Glycosaminoglycans have been isolated from guinea-pig basophilic leukocytes after treatment with proteolytic enzymes. Further treatment with chondroitin lyase AC, chondroitin lyase ABC, and heparan sulphate lyase was used to identify chondroitin sulphate (55%), dermatan sulphate (30%), and heparan sulphate (15%). 

After digestion of chondroitin 4- and 6-sulphates with chondroitin lyase ABC, the liberated disaccharides have been separated by h.p.l.c. on a weak anion-exchange resin. The method may be used in a study of the ratio of chondroitin 4- and 6-sulphates in cartilage. 

Biosynthesis. — Up to 56% of sulphated glycosaminoglycans synthesized by explant cultures of human and rabbit articular chondrocytes are located in the trypsin-digestible pericellular coat. ° Sulphate is incorporated into both D-glucopyranosyluronic acid and L-idopyranosyluronic acid residues in hybrid glycosaminoglycans by monolayers of chick embryo arterial fibroblasts. Several oligosaccharides, released on treatment with chondroitin lyase ABC and chondroitin lyase AC, have been characterized. 

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