Deficit in neuraminidase associated with mucolipidosis II (I-cell disease).
Using a tritiated sialyloligosaccharide as a substrate, the authors showed that mucolipidosis II is characterized by a lack of neuraminidase activity in leucocytes, while the other acidic hydrolases activities are normal. According to Ashwell, terminal galactose is the required signal for glycoproteins uptake by the cells. Thus, a neuraminidase deficit may explain the increase of sialylated hydrolases activities in the plasma and the non-recognition of these enzymes by cultured fibroblasts.
D006801:Humans; D006867:Hydrolases / Q000097:blood; D007962:Leukocytes / Q000201:enzymology; D009081:Mucolipidoses / Q000097:blood / Q000201:enzymology*; D009439:Neuraminidase / Q000172:deficiency*
D006867:Hydrolases; D009439:Neuraminidase