Complete biosynthesis of opioids in yeast

Toward opioids without poppy fields Producing opioids without having to depend on field-grown poppies would be of great benefit. Synthetic production could potentially produce more-effective drugs with fewer side effects. Now, Galanie et al. have engineered yeast to produce the opioid compounds thebaine and hydrocodone, starting from sugar (see the Perspective by Nielsen). The amounts produced so far are tiny compared with what would be needed commercially. Future optimization and scaleup are the next challenge. Science , this issue p. 1095 ; see also p. 1050