title: Steroid sulfotransferase in hamster epididymis.
abstract: Steroid sulfotransferase activity is present in the cytosol fraction of hamster epididymis. The activity of this enzyme is increased by magnesium ion. Cysteine is essential to assure optimal activity. Adenosine-3'-phosphate-5'-phosphosulfate is required as sulfate donor and an apparent Km of 62 microM was calculated. Inhibition studies suggest that this enzyme preferentially catalyzes the sulfurylation of the 3 beta-hydroxyl group of delta 5-steroids. An unusual feature of the enzyme is a pH optimum at pH 10.
mesh_terms: D000818:Animals; D002784:Cholesterol / Q000378:metabolism; D006224:Cricetinae; D003545:Cysteine / Q000378:metabolism; D004822:Epididymis / Q000201:enzymology*; D006863:Hydrogen-Ion Concentration; D007700:Kinetics; D008274:Magnesium / Q000378:metabolism; D008297:Male; D008647:Mesocricetus; D010724:Phosphoadenosine Phosphosulfate / Q000378:metabolism; D013256:Steroids / Q000494:pharmacology; D015238:Sulfotransferases; D013466:Sulfurtransferases / Q000037:antagonists & inhibitors / Q000378:metabolism*
chemical_list: D013256:Steroids; D010724:Phosphoadenosine Phosphosulfate; D002784:Cholesterol; D013466:Sulfurtransferases; D015238:Sulfotransferases; C028152:alcohol sulfotransferase; D008274:Magnesium; D003545:Cysteine