METABOLIC ENGINEERING OF THE MORPHINE PATHWAY IN OPIUM POPPY

The production and supply of morphine, codeine, and derived opiate analgesics depends on the cultivation of Papaver somniferum, opium poppy.
Only plants of the Papaver genus are able to synthesize morphinan alkaloids.
We have used transgenic methodologies to achieve metabolic engineering of the morphine pathway.
Constitutive over-expression of cDNAs encoding pathway enzymes such as codeinone reductase (COR) and salutaridinol acetyl transferase (SalAT) resulted in substantial and significant increases in the production of morphinan alkaloids, confirmed in replicated greenhouse and field trials over a number of generations.
Transgenic expression of hairpin RNA constructs resulted in RNAi silencing of COR and SalAT and the accumulation in the plants of non-morphinan intermediates (S)-reticuline and salutaridine, respectively.
This work illustrates the growing power of these approaches to modify complex secondary metabolic pathways and develop novel plants tailored as feedstocks for the changing needs of industry.

VI International Symposium on In Vitro Culture and Horticultural Breeding

P.J. Larkin

morphinan alkaloids, Papaver somniferum, secondary metabolites

https://doi.org/10.17660/ActaHortic.2009.829.16