Biosynthesis in vitro of a sulfated triglucosyl monoalkylmonoacylglycerol by rat gastric mucosa.
A sulfotransferase activity which catalyzes the transfer of the sulfate ester group from 3'-phosphoadenosine 5'-phosphosulfate to triglucosyl monoalkylmonoacylglycerol to form sulfated triglucosyl monoalkylmonoacylglycerol (SO3H-6Glc alpha 1 leads to 6Glc alpha 1 leads to 6Glc alpha 1 leads to 3-1,(3)-O-alkyl-2-O-acylglycerol) has been demonstrated in the rat gastric mucosa. The most enzyme activity was found in the cytosol fraction. Optimum enzymatic activity was obtained using the detergent Triton X-100, F1-, and Mg2+ at a pH of 7.8. The ATP, ADP, and dithiothreitol had inhibitory effects on the sulfotransferase. The enzymatic activity increased proportionally, over a given range, with increased concentrations of both substrates and of enzyme. The apparent Km of the enzyme for triglucosyl monoalkylmonoacylglycerol was 6.9 x 10(-5) M, and for 3'-phosphoadenosine 5'-phosphosulfate, 8.5 x 10(-7) M. The enzyme did not catalyze the transfer of sulfate to galactosylceramide. The results of compositional analyses and permethylation studies of the 35S-labeled product of the enzymatic reaction established that the sulfate ester group is located at C-6 on the terminal glucose residue.
D000818:Animals; D005753:Gastric Mucosa / Q000201:enzymology*; D006017:Glycolipids / Q000096:biosynthesis*; D008297:Male; D051381:Rats; D011919:Rats, Inbred Strains; D012969:Sodium Fluoride / Q000494:pharmacology; D013379:Substrate Specificity; D015238:Sulfotransferases; D013466:Sulfurtransferases / Q000378:metabolism*; D014018:Tissue Distribution
D006017:Glycolipids; D012969:Sodium Fluoride; C022321:PAPS sulfotransferase; D013466:Sulfurtransferases; D015238:Sulfotransferases