Chemoproteomics reveals the epoxidase enzyme for the biosynthesis of camptothecin in Ophiorrhiza pumila

The downstream biosynthetic route of camptothecin has remained unclear for more than half a century. Here, we discovered a P450 enzyme involved in camptothecin biosynthesis from plant by chemoproteomics, which lays the foundation for synthesis of camptothecin and highlights the effectiveness of chemoproteomic profiling for discovering unknown enzymes.