By Sola Ogundipe

Researchers at the University of Copenhagen’s Faculty of Science have modified a yeast cell to sense the active substances in cannabis and get it to turn red when it does.

The result paves the way for more actors to discover new medicinal substances and for a new type of drug test that can be done with a smartphone.

The researchers substituted the yeast cell’s sex drive with a sense of taste and smell that allows it to detect cannabinoids, the active substances in cannabis. Going one step further, the researchers made the yeast turn red or glow when it successfully detects cannabinoids. The study is published in Nature Communications.

“We have made a living sensor out of the yeast cell, which can now sense cannabinoids or molecules that have the same function as cannabinoids even if they look very different than cannabinoids. Among other things, the biosensor can be used to look for new substances with the same properties as cannabinoids.

This could democratize medicinal development so that pharmaceutical companies aren’t the only ones equipped to discover new substances,” says Professor Sotirios Kampranis of the Department of Plant and Environmental Sciences, who headed the research.

Humans use hundreds of different GPCRs (G-protein-coupled receptors) to taste and smell.

Along with his research colleagues, Professor Kampranis swapped the GPCR that yeast cells use to sense the opposite sex in an environment, with the GPCR, humans use to recognise cannabinoids.

 At the same time, the researchers complemented the yeast cell’s genetic material with a set of new genes that make it turn red or even glow when it senses cannabinoids nearby.

“The yeast cell now emits a signal when there are cannabinoids in the yeast cell’s environment. This allows us to screen thousands of plants for substances with therapeutic potential.

And we can also investigate whether people are on drugs or whether someone is trying to smuggle illegal cannabinoids or “designer drugs” through an airport checkpoint,” explains  Kampranis.