Impaired degradation of keratan sulphate by Morquio A fibroblasts.
Upon incubation of keratan [35S]sulphate with normal fibroblasts both [35S]sulphate and N-acetylglucosamine 6-[35S]sulphate are liberated. From the products obtained after digestion with various mutant fibroblasts and with purified N-acetylgalactosamine 6-sulphate sulphatase we suggest that (i) [35S]sulphate is released almost exclusively from galactose 6-sulphate residues; (ii) N-acetylgalactosamine 6-sulphate sulphatase exhibits galactose 6-sulphate sulphatase activity; (iii) both sulphatase activities are deficient in Morquio disease type A.
D002460:Cell Line; D002811:Chondroitinsulfatases / Q000378:metabolism; D005347:Fibroblasts / Q000201:enzymology / Q000378:metabolism*; D006025:Glycosaminoglycans / Q000378:metabolism*; D006801:Humans; D007632:Keratan Sulfate / Q000378:metabolism*; D009085:Mucopolysaccharidosis IV / Q000201:enzymology / Q000378:metabolism*; D013429:Sulfatases / Q000378:metabolism
D006025:Glycosaminoglycans; D007632:Keratan Sulfate; D002811:Chondroitinsulfatases; D013429:Sulfatases; C018719:N-acetylglucosamine-6-sulfatase