How plant alkaloids are made

Plants make an astounding variety of bioactive compounds, which we take full advantage of. These include the caffeinated beverages we that drink, a plethora of prescribed drugs and the majority of narcotics. However, because of the complexity of plants, the details of how these compounds are made are often unknown. Here, Elizabeth Sattely and colleagues report the biosynthetic pathway of colchicine, a medicinally relevant alkaloid that has been used to treat gout and inflammation since Ancient Egypt. They elucidate eight genes from the flame lily plant en route to a colchicine precursor, including a cytochrome P450 enzyme that catalyses a ring-expansion reaction to form the compound scaffold. The entire metabolic pathway is recapitulated in Nicotiana benthamiana, a model plant, which will facilitate further engineering efforts for colchicine and related alkaloids.