Engineered strains of laboratory yeast can make small quantities of opiates that are used in pain medications, such as hydrocodone.

Poppy farms are currently the main source of opiates, but production is uncertain because of weather, pests and other factors. Christina Smolke of Stanford University in California and her colleagues introduced more than 20 enzymes into a yeast strain, including some from poppy plants. After 120 hours of growth using simple sugars, the yeast produced thebaine — which drug makers convert to codeine and other drugs — and hydrocodone.

If the yields could be increased by more than 100,000 times, such microbes could provide an alternative opiate source, the authors say.

Science http://doi.org/6s8 (2015)