PURIFICATION, CLONING, AND BACTERIAL EXPRESSION OF RETINOL DEHYDRATASE FROM SPODOPTERA-FRUGIPERDA

Anhydroretinol and 14-hydroxy-4,14-retro-retinol, retro-retinoids endo genous to both mammals and insects, act as agonist and antagonist, res pectively, in controlling proliferation in lymphoblasts and other reti nol-dependent cells. We describe here the identification, purification , cloning, and bacterial expression of the enzyme retinol dehydratase, which converts retinol to anhydroretinol in Spodoptera frugiperda. Re tinol dehydratase has nanomolar affinity for its substrate and is, the refore, the first enzyme characterized able to utilize free retinol at physiological intracellular concentrations. The enzyme shows sequence homology to the sulfotransferases and requires 3'-phosphoadenosine 5' phosphosulfate for activity.