The Substrate Spectra of Pentaerythritol Tetranitrate Reductase, Morphinone Reductase, N‐Ethylmaleimide Reductase and Estrogen‐Binding Protein in the Asymmetric Bioreduction of Activated Alkenes

Abstract Four flavoproteins from the old yellow enzyme (OYE) family, pentaerythritol tetranitrate (PETNR) reductase, N ‐ethylmaleimide reductase (NEMR), morphinone reductase (MorR) and estrogen‐binding protein (EBP1), exhibited a broad substrate tolerance by accepting conjugated enals, enones, imides, dicarboxylic acids and esters, as well as a nitroalkene and therefore can be employed for the asymmetric bioreduction of carbon‐carbon double (CC) bonds. In particular, morphinone reductase and estrogen‐binding protein often showed a complementary stereochemical preference in comparison to that of previously investigated OYEs.