Biotechnology: Brewing up cannabinoids in yeast

Several major cannabinoids (chemical compounds found in cannabis) have been produced by genetically modified yeast, reports a paper published online this week in Nature. This work could lead to the efficient production of different types of cannabinoids, independently of cannabis cultivation.

Specific cannabinoids have been approved as prescription drugs in several countries for treating various illnesses. Cannabinoids are currently derived from the cannabis plant, where they are found at relatively low abundance. This, in addition to their chemical complexity, has hampered the large-scale production of cannabinoids.

Jay Keasling and colleagues genetically modified brewer’s yeast (Saccharomyces cerevisiae) to produce cannabinoids via biosynthesis. The authors introduced cannabis genes into the yeast’s metabolic pathways to produce cannabinoid precursor molecules, such as olivetolic acid, from the simple sugar galactose. From olivetolic acid, the yeast was able to produce the key cannabinoid cannabigerolic acid (CBGA), which could in turn be used to produce Δ9-tetrahydrocannabinolic acid (THCA) and cannabidiolic acid (CBDA).

The authors also demonstrated that synthetic cannabinoids, such as chemically modified THCA, could be produced from fatty acids instead of galactose. Together, these results lay the foundation for the large-scale production of both natural and synthetic cannabinoids, which could improve pharmacological research into these compounds.