Scientists genetically modify a tobacco plant to produce COCAINE in its leaves
- Cocaine occurs naturally in the leaves of the Erythroxylum coca plant
- Scientists have discovered the chemical processes involved in its synthesis
- They modified a relative of a tobacco plant to produce two essential enzymes
- These turned a precursor molecule in their leaves into the backbone of cocaine.
A relative of the tobacco plant called Nicotiana benthamiana it has been genetically modified to produce cocaine in its leaves.
Cocaine occurs naturally in the leaves of the Erythroxylum coca plant, and scientists set out to recreate this process in N. benthamiana.
A team from the Kunming Institute of Botany in China modified N. benthamiana to produce two enzymes that generate cocaine when its leaves are dried.
The breakthrough could lead to a way to make cocaine or produce chemically similar compounds for medicinal purposes.
Cocaine (pictured) is what is known as a “tropane alkaloid”, which occurs naturally and has strong psychoactive effects. While notorious as an illegal drug, it has also been used in medical practices as a local anesthetic or to narrow blood vessels to stop bleeding.
The team at the Kunming Institute of Botany in China altered N. benthamiana (pictured) to produce two enzymes that generate cocaine when its leaves are dried.
HOW THEY DID IT?
The scientists discovered that two enzymes are essential for converting a precursor chemical, MPOA, into a section of the cocaine molecule, methylecgonone.
Knowing this, they were able to recreate the biosynthesis of cocaine from the leaves of N. benthamiana.
Tobacco leaves contain a substance called omitin, which is chemically similar to MPOA and is also converted by both enzymes.
They were genetically modified N. benthamiana to produce the two enzymes itself, and synthesize cocaine.
Cocaine is what is known as a ‘tropane alkaloid’, which has strong psychoactive effects in its crystalline form.
“Cocaine (hydrochloride) is a highly addictive drug that acts as a central nervous system stimulant and a short-acting local anaesthetic,” the NHS explains.
‘It is extracted from the leaves of coca plants and is usually inhaled.’
The addictive alkaloid is produced naturally by the and coke plant, and can be extracted by drying its leaves.
Although cocaine is notorious as an illegal drug, it has also been used in medical practices as a local anesthetic or to narrow blood vessels and stop bleeding.
However, pharmaceutical companies are limited in how they can produce the drug, as the key steps in its biosynthesis remain a mystery.
Until now, scientists did not know how the precursor chemical MPOA is converted to a section of the cocaine molecule, methylecgonone.
In his article, published in the Journal of the American Chemical Societythe scientists finally figured out what was missing.
Two enzymes, EnCYP81AN15 and EnMT4, are essential for this conversion reaction to form methylecgonone.
The scientists discovered that two enzymes, EnCYP81AN15 and EnMT4, are essential for converting a precursor chemical, MPOA, into a section of the cocaine molecule, methylecgonone.
The addictive alkaloid cocaine is produced naturally by the and coke plant (pictured), and can be extracted by drying its leaves
Armed with this knowledge, the researchers turned to the tobacco plant, whose leaves contain a substance called ornithine, which is chemically similar to MPOA and is also converted by the two enzymes.
Using genetic modification, the researchers were able to alter the N. benthamiana plant to produce the enzymes themselves.
This modification meant that the tobacco plant could produce methylecgonone – the backbone of cocaine – in its leaves.
Experiments showed that the modified plant could produce around 400 nanograms of cocaine per milligram of dry leaf, considerably less than a coca plant.
Speaking to New Scientist, Sheng-Xiong Huang, a co-author of the study, explained: “Currently, the available production of cocaine in tobacco is not sufficient to meet large-scale demand.”
However, the team hopes that their research could lead to the modification of other organisms that could produce it on a larger scale, such as bacteria.
Burnt seeds from an ancient fireplace show that humans used the tobacco plant 12,300 years ago
The discovery of four charred seeds in an ancient chimney in Utah, USA, has revealed that humans used tobacco 12,300 years ago.
Experts from the Wild West Anthropological Research Group found the seeds while excavating a hunter-gatherer camp, ‘Wishbone’, in the Great Salt Lake desert.
At other ancient archaeological sites, it has been argued that the presence of tobacco seeds was a byproduct of chewing tobacco.
The findings indicate that tobacco was being used by some of the first human groups to reach the Americas, thousands of years before their domestication.
This, the team explained, could help us understand the cultural driving forces that led to the use, cultivation, and eventual domestication of tobacco plants.
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Charred Tobacco (Nicotiana) seed dug up from old hearth