Free N-acetylneuraminic acid in tissues in Salla disease and the enzymes involved in its metabolism.
Salla disease is a lysosomal storage disorder of unknown etiology, characterized biochemically by increased urinary excretion of N-acetylneuraminic acid. This compound has now been shown to occur in abnormally large amounts in liver and cultured skin fibroblasts from these patients. Quantification of N-acetylneuraminic acid was performed using a new gas-chromatography/mass spectrometric single-ion method which is sensitive and specific. No abnormalities in the activity of several enzymes involved in sialic acid metabolism (N-acetylneuraminate:pyruvate lyase, neuraminidase, CMP-N-acetylneuraminate N-acylneuraminohydrolase and CTP:N-acyl-neuraminate cytidylyltransferase) were demonstrable. A possible explanation for the defect is a malfunctioning active transport of N-acetylneuraminic acid across the lysosomal membrane.
D005347:Fibroblasts / Q000378:metabolism; D005732:Gangliosides / Q000378:metabolism; D006020:Glycopeptides / Q000378:metabolism; D006801:Humans; D008099:Liver / Q000378:metabolism; D008247:Lysosomes / Q000378:metabolism; D008661:Metabolism, Inborn Errors; D019158:N-Acetylneuraminic Acid; D000216:N-Acylneuraminate Cytidylyltransferase; D009439:Neuraminidase / Q000378:metabolism; D007652:Oxo-Acid-Lyases / Q000378:metabolism; D010727:Phosphoric Diester Hydrolases / Q000378:metabolism; D012794:Sialic Acids / Q000378:metabolism*
D005732:Gangliosides; D006020:Glycopeptides; D012794:Sialic Acids; D000216:N-Acylneuraminate Cytidylyltransferase; D010727:Phosphoric Diester Hydrolases; C010265:CMP-N-acylneuraminate phosphodiesterase; D009439:Neuraminidase; D007652:Oxo-Acid-Lyases; C018728:N-acetylneuraminate lyase; D019158:N-Acetylneuraminic Acid