title: Selective hydrolysis of chondroitin sulfates by hyaluronidase.
abstract: Chondroitin 4-sulfate and chondroitin 6-sulfate were incubated with testicular hyaluronidase in the presence of excess beta-glucuronidase. The beta-glucuronidase caused rapid removal of the nonreducing terminal beta-D-glucuronosyl residues from the oligosaccharides formed by the action of the hyaluronidase, destroying the oligosaccharide acceptors required for the transglycosylation activity of hyaluronidase and releasing free D-glucuronic acid at a rate that was equal to the rate of the hyaluronidase-catalyzed hydrolysis. When hyaluronidase was assayed at 37 degrees C in the presence of 0.05 M NaCl, 0.05 M Na2SO4, and 0.1 M sodium acetate at pH 5, chondroitin 4-sulfate was hydrolyzed at 1.5 times the rate found for chondroitin 6-sulfate. When hyaluronidase was assayed at 45 degrees C in 0.06 M sodium acetate at pH 6, chondroitin 4-sulfate was hydrolyzed at 8 times the rate observed for chondroitin 6-sulfate. Under the pH5 conditions, the chondroitin 4-sulfate was converted to a mixture of tri- and pentasaccharides, while the chondroitin 6-sulfate was converted primarily to a mixture of penta- and heptasaccharides, with only a small amount of trisaccharide. Under the pH 6 conditions, the chondroitin 4-sulfate was converted to a mixture of penta- and heptasaccharides, with only a small amount of trisaccharide, but the products from chondroitin 6-sulfate were a mixture of oligosaccharides ranging in degree of polymerization from 7 to 25 monosaccharides per oligosaccharide. End-group analyses of the products formed at pH 6 showed that both substrates were cleaved preferentially at the glycosidic bonds of the 4-sulfated disaccharides.(ABSTRACT TRUNCATED AT 250 WORDS)
mesh_terms: D000818:Animals; D002356:Cartilage; D002807:Chondroitin / Q000031:analogs & derivatives*; D002809:Chondroitin Sulfates / Q000378:metabolism*; D006821:Hyaluronoglucosaminidase / Q000378:metabolism*; D006868:Hydrolysis; D007700:Kinetics; D008297:Male; D009844:Oligosaccharides; D012754:Sharks; D013379:Substrate Specificity; D013737:Testis / Q000201:enzymology; D014907:Whales
chemical_list: D009844:Oligosaccharides; D002807:Chondroitin; D002809:Chondroitin Sulfates; D006821:Hyaluronoglucosaminidase