Sanfilippo syndrome type C: deficiency of acetyl-CoA:alpha-glucosaminide N-acetyltransferase in skin fibroblasts.
Removal of N-sulfated glucosamine residues during degradation of heparan sulfate is accomplished by the sequential action of three enzymes. Action of sulfamidase results in the formation of alpha-glucosaminide residues. Removal of these groups requires conversion to alpha-N-acetylglucosaminide by the action of an acetyltransferase in the presence of acetyl-CoA, followed by hydrolysis by alpha-N-acetylglucosaminidase. In fibroblast homogenates from three patients with Sanfilippo syndrome type C (mucopolysaccharidosis III C), a biochemical variant of the Sanfilippo syndrome, complete deficiency of the acetyl-CoA:alpha-glucosaminide N-acetyltransferase activity was detected. Activities of all lysosomal hydrolases known so far to degrade mucopolysaccharides, including those of sulfamidase and alpha-N-acetylglucosaminidase, were in the range of controls. Acetyl-CoA:alpha-glucosaminide N-acetyltransferase activity was normal in fibroblasts of patients with other genetic mucopolysaccharidoses, including Sanfilippo syndrome A and B.
D000123:Acetyltransferases / Q000172:deficiency*; D004590:Electrophoresis, Paper; D005347:Fibroblasts / Q000201:enzymology; D005944:Glucosamine; D006497:Heparan Sulfate / Q000378:metabolism; D006801:Humans; D006863:Hydrogen-Ion Concentration; D008247:Lysosomes / Q000201:enzymology; D009084:Mucopolysaccharidosis III / Q000201:enzymology
D000123:Acetyltransferases; D005944:Glucosamine; D006497:Heparan Sulfate