THE HYDROLYSIS OF ESTRONE SULFATE AND DEHYDROEPIANDROSTERONE-SULFATE BY HUMAN STEROID SULFATASE EXPRESSED IN TRANSFECTED COS-1 CELLS

Whether the same or distinct steroid sulphatases (STS) are involved in the hydrolysis of alkyl and aryl steroid sulphates remains controvers ial. We have examined the ability of a placental steroid sulphatase to hydrolyse oestrone sulphate and/or dehydroepiandrosterone sulphate (D HA-S) by expressing the enzyme in COS-1 cells. Using either intact cel ls or broken cell preparations, the expressed sulphatase was found to hydrolyse both oestrone sulphate and DHA-S. The catalysis of oestrone sulphate and DHA-S by the expressed sulphatase was almost completely a bolished by the steroid sulphatase inhibitor, oestrone-3-O-sulphamate. It is concluded that both alkyl and aryl steroid sulphates can be hyd rolysed by the same steroid sulphatase.