Scientists have made a genetic discovery in poppies that could lead to the development of more effective painkillers.
The gene, called STORR, is only found in poppy species that can produce morphinans. This gene is believed to have evolved when encoding oxidase and reductase enzymes merged millions of years ago, leading to morphine production, the University of York reported.
Scientists have now identified poppy plants that were not able to produce morphine or codeine, and instead acquired the compound (S)-reticuline. These outliers carry mutations in the STORR gene that cause a "roadblock" in the pathway to morphine production. The scientists demonstrated the non-mutated wild type gene can overcome this roadblock by expressing it in yeast cells.
"Plants produce an amazing array of natural chemicals. Discovery of this STORR gene fusion provides us with new insight into how poppy plants have evolved to produce the most effective painkillers known to man," said Professor Ian Graham, who led the research in the Centre for Novel Agricultural Products, based in the Department of Biology at the University of York.
These naturally occurring opiates can be used to create powerful anesthetics such as morphine, codeine and thebaine. Morphine and codeine can be directly used as painkillers, but the baine is more commonly used as a starting point for synthesis of semi-synthetic opiates including hydrocodone.
"Opium poppy is one of the most important medicinal plants. The formation of the fusion protein was probably a key evolutionary event in its ability to synthesis pharmaceutically important morphinan alkaloids," said lead author Thilo Winzer.
The discovery of the STORR gene could allow for an alternative supply route for active pharmaceutical ingredients.
The findings were reported in a recent edition of the journal Science.
