抄録
APS formation catalyzed by purified ATP-sulphurylase of Porphyra yezoensis was demon-strated. APS accumulated in the incubated enzyme mixture was separated on a DEAE-Toyo pearl 650M column, and identified by anion-exchange HPLC and TLC. UV absorption spectra, acid-lability, and equimolar contents in adenine, ribose, phosphate and sulphate also substantiated the identity. The low accumulation of APS suggested the presence of some difficulties in the APS synthesizing reaction.
ATP-sulphurylase (EC 2. 7. 7. 4.) catalyzes the first step in the sulphate activating reaction: