Structure Model-Guided Reprogramming Enables Functional Interconversion of Phomactatriene and Verticillene Synthases

Terpenoids represent the most structurally diverse class of natural products on Earth. Terpene synthases are key enzymes for constructing the complex and varied terpene skeletons by catalyzing the formation of multiple carbon-carbon bonds. Phomactatriene and verticillene family natural products are both classified as bicyclic diterpenoids, sharing a unique bicyclo[9.3.1]pentadecane skeleton. In this study, we used genome mining to identify the phomactatriene synthase SiPS from bacteria, together with two verticillene synthases, LxVS and AxVS. Our DFT calculations revealed that the rearrangement pathways for compounds in the phomactatriene and verticillene families follow a shared biosynthetic route. Furthermore, through comparative structural model analyses of the phomactatriene and verticillene synthases, we employed molecular modelling and site-directed mutagenesis to facilitate functional interconversion between these distinct terpene synthases. This work enhances our understanding of terpene biosynthesis and the potential for engineering terpene synthases for biotechnological applications.