Scientists Have Genetically Modified Beer Yeast to Produce Cannabinoids THC and CBD

The rise of legalized cannabis tends to be positioned as an existential threat to the beer industry, but biologists at the University of California, Berkeley, have (in a sense) found a way for the two to work together. According to results published in the February 27 issue of Nature, they’ve successfully engineered classical brewer’s yeast (Saccharomyces cerevisiae) to transform sugars into a range of different cannabinoids, including THC and CBD.

THC is of course the most famous psychoactive compound found in cannabis—the reason for marijuana’s “high” experienced by users. Cannabidiol (CBD), meanwhile, is another cannabinoid that has shown promise as a medical treatment for anxiety and chronic pain, although its therapeutic effects are still being studied. And both can apparently be produced via genetically modified brewer’s yeast, without a cannabis plant ever being involved.

Researchers needed to make 16 genetic modifications to allow their yeast strain to transform the sugar galactose into the inactive forms of both THC and CBD—they’re activated by heat, which is why cannabis is traditionally smoked. The end hope would be that this fermentation process would allow the mass production of THC and CBD in ways that are more cost efficient than harvesting from cannabis plants.

Now, for the bad news: The current process is nowhere near efficient enough, with Nature saying that the yields would need to be increased 100-fold in order to be made cost competitive. That may sound impossible, but further modification of the yeast strain might make it entirely doable. The Nature piece quotes a cannabis analyst who predicts these forms of cannabinoid production could be cost-effective within two years, which is just over the horizon. A similar yeast-engineering process has already been used to successfully produce anti-malarial drugs.

Of particular interest is the fact that the Berkeley team has also engineered their yeast to transform various fatty acids into new cannabinoids that don’t exist in nature. If these compounds are found to also have therapeutic effects, similar to CBD, it could spark a wave of new patents and treatments.

So, it sounds like cannabis owes beer a thank-you on this one. That, or the beer world is about to get very angry at its own turncoat yeast for this filthy betrayal.