Degradation of keratan sulfate by beta-N-acetylhexosaminidases in GM2-gangliosidosis.
We have prepared a new substrate from a keratan sulfate-derived-oligosaccharide (2-acetamido-2-deoxyglucosyl-(1--3)-[1-3H] Galactitol), which is necessary to measure beta-N-acetylhexosaminidase activity. This substrate was prepared from a cornea keratan sulfate by digestion with endo-beta-galactosidase, followed by isolation of disaccharide on gel filtration chromatography and chemical desulfation. Using this substrate, we found that a striking deficiency of beta-N-acetylhexosaminidase activity was present in the skin fibroblasts of patients with Sandhoff disease but not in Tay-Sachs disease. Both beta-N-acetyl-hexosaminidase A & H contributed to the catabolism of keratan sulfate.
D002478:Cells, Cultured; D002848:Chromatography, DEAE-Cellulose; D002854:Chromatography, Paper; D004187:Disaccharides / Q000138:chemical synthesis; D005347:Fibroblasts / Q000201:enzymology; D006025:Glycosaminoglycans / Q000378:metabolism*; D006596:Hexosaminidases / Q000172:deficiency* / Q000378:metabolism; D006801:Humans; D007632:Keratan Sulfate / Q000378:metabolism*; D012497:Sandhoff Disease / Q000201:enzymology*; D013661:Tay-Sachs Disease / Q000201:enzymology*; D001619:beta-N-Acetylhexosaminidases
D004187:Disaccharides; D006025:Glycosaminoglycans; C034788:2-acetamido-2-deoxyglucosylgalactitol; D007632:Keratan Sulfate; D006596:Hexosaminidases; D001619:beta-N-Acetylhexosaminidases