Scientists from the University of Berkeley in California have genetically engineered brewer's yeast to create cannabinoids -- the active ingredients found in cannabis plants.

The fermentation process transforms the altered yeast into tetrahydrocannabinol (THC) and cannabidiol (CBD), the major cannabinoids which are known for its medicinal and potential therapeutic properties. The team needed to create 16 genetic modifications to transform galactose, a sugar found in yeast, into inactive forms of THC or CBD. Heating the cannabinoids shifts them into their active forms. They were also able to convert different fatty acids into cannabinoids that do not occur naturally in nature from the engineered yeast.

For more details, read the news article in Nature.