Directed Evolution of an Amine Oxidase for the Preparative Deracemisation of Cyclic Secondary Amines

Abstract

Off the rac. Directed evolution of the amine oxidase from Aspergillus niger (MAO-N), by using 1-methyltetrahydroisoquinoline as the target substrate, led to the identification of a variant enzyme (Asn336Ser/Ile246Met) that possessed a greater kcat value (5.5-fold) than the parent as well as high enantioselectivity (see scheme). This new variant was used for the deracemisation of cyclic secondary amines on a preparative scale.