Abstract: The invention relates to recombinant host cells that expresses one or more genes encoding a cytochrome P450 enzyme capable of N-demethylating and/O-demethylating reticuline and/or derivatives thereof, and also methods of producing a N-demethylated and/or O-demethylated reticuline and/or derivatives thereof, comprising cultivating the recombinant host of the invention in a culture medium under conditions in which the one or more genes encoding the cytochrome P450 enzymes is/are expressed. The reticuline and derivatives thereof are useful for providing access to naturally unavailable and chemically difficult-to-produce starting materials for opioids.

Abstract: Disclosed are methods for preparing buprenorphine from, for example, compounds such as nororipavine and northebaine.

Abstract: Recombinant microorganisms, plants, and plant cells are disclosed that have been engineered to have reduced levels or activity of one or more alcohol dehydrogenases or aldehyde reductases thereby increasing the production of benzylisoquinoline alkaloids and/or benzylisoquinoline alkaloid precursors.