How is morphine made from poppies?

Chuck Bednar for – @BednarChuck

In a discovery that could lead to the development of more effective painkillers, researchers from the University of York and GlaxoSmithKline Australia have discovered a gene that plays a key role in the synthesis of the morphinan class of alkaloids in poppies.

As the authors of the study report in the latest edition of the journal Science, the gene is known as STORR and is only found in poppy species that produce morphians – a group including painkillers such as morphine and codeine. This gene evolved when a pair of other genes that encode oxidase and reductase enzymes joined together millions of years ago.

The resulting gene fusion plays a key role in the production of morphine, the research team pointed out in a statement. They hope that this discovery will enable the breeding poppies that produce various substances, including the anti-cancer compound noscapine. They note that this is the last gene required for the genetic engineering of morphine production in microbes.

Discovery will enable morphine, codeine production in yeast

“This is a major breakthrough since it describes the gene responsible for the last uncharacterized step in the pathway to morphine and codeine synthesis in poppy plants,” lead researcher, Professor Ian Graham, told redOrbit via email on Thursday.

“The gene itself is highly unusual as it resulted from the combining of two other genes millions of years ago,” he added. “Now that the identity of this gene is known, it can be used to improve production of valuable painkillers and other compounds… [and] it also completes the toolkit of genes that are needed to engineer production of morphine and codeine in yeast.”

The discovery came when Professor Graham and his colleagues identified poppy plants that could not produce morphine or codeine, but instead accumulated another compound called (S)-reticuline. These plants carried mutations in the STORR gene, preventing morphine production in poppies, and the team discovered that the non-mutated type of the gene can overcome this obstacle by expressing it in yeast cells.

“This is just one example of nature’s treasure trove of high value chemicals produced in plants,” Professor Graham told redOrbit. “Our ongoing work is focused on discovering how some of these others are made so that we can develop them for the benefit of society.”


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