Chalcone synthase is the first committed enzyme in the plant flavonoid biosynthesis pathway, yet shows low product specificity in vitro. Here Waki et al. show that chalcone isomerase-like proteins bind to and reduce the catalytic promiscuity of chalcone synthase, ensuring efficient flavonoid production in planta.
- Toshiyuki Waki
- Ryo Mameda
- Toru Nakayama