The evolution of tropane alkaloids: Coca does it differently.

It is undeniable that tropane alkaloids (TAs) have been both beneficial and detrimental to human health in the modern era. Understanding their biosynthesis is vital for using synthetic biology to engineer organisms for pharmaceutical production. The most parsimonious approaches to pathway elucidation are traditionally homology-based methods. However, this approach has largely failed for TA biosynthesis in angiosperms. In the recent decade, significant progress has been made in elucidating the TA synthesis pathway in Erythroxylum coca, highlighting the parallel development of TAs in both the Solanaceae and Erythroxylaceae families. This separate evolutionary path has uncovered substantial divergence in the TAs formed by E. coca and distinct enzymatic reactions that differ from the traditional TA biosynthetic pathway found in TA-producing nightshade plants.