Open AccessPresence and characterization of glycolipid sulfotransferase in human cancer serum
Author(s) -
GASA Shinsei,
ČASL MartinTino,
MAKITA Akira,
SAKAKIBARA Naoyuki,
KOYANAGI Tomohiko,
ATSUTA Tomoyoshi
Publication year - 1990
Publication title -
european journal of biochemistry
Language(s) - English
Resource type - Journals
eISSN - 1432-1033
pISSN - 0014-2956
DOI - 10.1111/j.1432-1033.1990.tb15490.x
Subject(s) - sulfotransferase , sulfation , glycolipid , enzyme , chemistry , biochemistry , sulfate , enzyme assay , organic chemistry
Sulfotransferase, which catalyzes sulfation of the carbohydrate of galactosylceramide (GalCer) and is localised in the Golgi membrane of cells, was assayed for activity in human serum. To do this, an organic solvent was added to the incubated reaction mixture containing GalCer as an acceptor and phosphoadenosine phospho[ 35 S]‐sulfate as a donor of sulfate to dissociate the synthesized sulfolipid from serum protein. This was followed by isolation of the sulfolipid on an anion‐exchange column. Through this procedure, human serum was found to contain sulfotransferase activity. The serum enzyme was activated by Mn 2+ . K m values of the enzyme for GalCer and ‘active sulfate’ were 4.6 μM and 5.2 μM, respectively. The enzyme activity was assayed in sera of cancer patients. The serum activity (mean ± SE, 0.27 ± 0.027 pmol ±μl −1 · h −1 ) in renal cell carcinoma patients, whose activity has been demonstrated to be elevated, was significantly ( P < 0.005) increased compared to that of the normal control (mean ± SE, 0.18 ± 0.0014 pmol ±μl −1 · h −1 ) and of other urological tumors examined.