HUMAN PHENOLSULFOTRANSFERASES - CHIRAL SUBSTRATES AND EXPRESSION IN HEP G2 CELLS

Enzymatic sulfation of chiral phenolic ethanolamine drugs, e.g. beta-a gonists, has been shown to be stereoselective in humans. The reaction appears to be specific for the monoamine (M) form of the phenolsulfotr ansferases (PSTs). In further studies of the stereochemistry of this r eaction, we have found the hepatoblastoma-derived cell line Hep G2 to be an excellent human model. These cells contain the M form PST in qua ntities exceeding those of human liver by about 4-fold. Thus, sulfate conjugates of the beta-agonist drugs can easily be synthesized for sub sequent structural and enzyme kinetic studies. Although less abundant, the phenol (P) form PST as well as dehydroepiandrosterone sulfotransf erase are also expressed in the Hep G2 cells.