Isolation and characterization of a cDNA encoding (S)-cis-N-methylstylopine 14-hydroxylase from opium poppy, a key enzyme in sanguinarine biosynthesis

► A cDNA encoding a P450 (CYP82N4) involved in sanguinarine biosynthesis was isolated from Papaver somniferum (opium poppy). ► Expression of the corresponding gene was detected in opium poppy roots and elicitor-treated cell suspension cultures. ► The CYP82N4 cDNA was expressed in Saccharomyces cerevisiae. ► Recombinant CYP82N4 converted N-methylated protoberberines to protopine alkaloids.