glucosylceramide f-glucosidase activity
نویسنده
چکیده
Glucosylceramide ,-glucosidase is a membrane-bound lysosomal hydrolase that is activated by acidic lipids, the most effective of which is phosphatidylserine (PtdSer), and an activator protein, saposin C. This report documents effects of Ca2+ ions on PtdSerand saposin C-enhanced ,-glucosidase activity. Ca2+ either increased or decreased enzyme activity, depending on (1) the concentration of phospholipid, and (2) the presence or absence of saposin C. At PtdSer concentrations between 7.6 and 76,M, in the absence of saposin C, Ca2+ caused an increase in ,glucosidase activity up to 3 times that measured with PtdSer
منابع مشابه
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