Non-radioactive adenosine 5'-phosphosulfate sulfotransferase assay by coupling with sulfite reductase and O-acetylserine(thiol)lyase.
Adenosine 5'-phosphosulfate (APS) sulfotransferase is thought to be an enzyme that transfers the sulfo-group of APS to a carrier compound with a thiol group in the assimilatory sulfate reduction pathway of higher plants. We developed a rapid, non-radioactive assay for APS sulfotransferase. Sulfite released by APS sulfotransferase reaction in the presence of excess dithiothreitol was further converted to cysteine by coupling with yeast sulfite reductase and cabbage O-acetylserine(thiol)lyase. The cysteine thus formed was measured colorimetrically. By this method, 5 to 300 nmol of sulfite could be assessed. When the method was applied to APS sulfotransferase, the enzyme activity was APS-dependent with the partially purified enzyme. We could also detect APS sulfotransferase activity in some higher plants by this method.
Ara
T
T
Department of Agricultural Chemistry, Faculty of Agriculture, Kyoto University, Japan.
Sekiya
J
J
D019757:Carbon-Oxygen Lyases; D003547:Cysteine Synthase; D008190:Lyases / Q000378:metabolism*; D009097:Multienzyme Complexes; D050862:Oxidoreductases Acting on Sulfur Group Donors / Q000378:metabolism*; D010944:Plants / Q000201:enzymology; D029701:Saccharomyces cerevisiae Proteins; D013447:Sulfites / Q000378:metabolism; D015238:Sulfotransferases / Q000378:metabolism*
D009097:Multienzyme Complexes; D029701:Saccharomyces cerevisiae Proteins; D013447:Sulfites; D050862:Oxidoreductases Acting on Sulfur Group Donors; D003547:Cysteine Synthase; C103381:MET17 protein, S cerevisiae; C018725:O-acetylhomoserine (thiol)-lyase; D015238:Sulfotransferases; C081239:adenosine 5'-phosphosulfate sulfotransferase; D008190:Lyases; D019757:Carbon-Oxygen Lyases