Redesigning the Molecular Choreography to Prevent Hydroxylation in Germacradien-11-ol Synthase Catalysis

Natural sesquiterpene synthases have evolved to make complex terpenoids by quenching reactive carbocations either proton transfer or hydroxylation (water capture), depending on their active site. Germacradien-11-ol synthase (Gd11olS) from Streptomyces coelicolor catalyzes the cyclization of farnesyl diphosphate (FDP) into hydroxylated germacradien-11-ol. Here, we combine experiment and simulation guide redesign its site pocket avoid product. Molecular dynamics simulations indicate two regions between which water molecules can flow that are responsible for hydroxylation. Point mutations selected residues result in variants predominantly form a nonhydroxylated product, identify as isolepidozene. Our results how these subtly change molecular choreography Gd11olS thereby pave way engineering terpene terpenoid products.