title: A (-)-kolavenyl diphosphate synthase catalyzes the first step of salvinorin A biosynthesis in Salvia divinorum.
abstract: Salvia divinorum (Lamiaceae) is an annual herb used by indigenous cultures of Mexico for medicinal and ritual purposes. The biosynthesis of salvinorin A, its major bioactive neo-clerodane diterpenoid, remains virtually unknown. This investigation aimed to identify the enzyme that catalyzes the first reaction of salvinorin A biosynthesis, the formation of (-)-kolavenyl diphosphate [(-)-KPP], which is subsequently dephosphorylated to afford (-)-kolavenol. Peltate glandular trichomes were identified as the major and perhaps exclusive site of salvinorin accumulation in S. divinorum. The trichome-specific transcriptome was used to identify candidate diterpene synthases (diTPSs). In vitro and in planta characterization of a class II diTPS designated as SdKPS confirmed its activity as (-)-KPP synthase and its involvement in salvinorin A biosynthesis. Mutation of a phenylalanine into histidine in the active site of SdKPS completely converts the product from (-)-KPP into ent-copalyl diphosphate. Structural elements were identified that mediate the natural formation of the neo-clerodane backbone by this enzyme and suggest how SdKPS and other diTPSs may have evolved from ent-copalyl diphosphate synthase.
authors.affiliation: Institute of Biological Chemistry, Washington State University, Pullman, WA 99164,USA.
authors.forename: Xiaoyue
authors.initials: X
authors.lastname: Chen
authors.affiliation: Institute of Biological Chemistry, Washington State University, Pullman, WA 99164,USA.
authors.forename: Anna
authors.initials: A
authors.lastname: Berim
authors.affiliation: Bioagricultural Sciences and Pest Management, Colorado State University, Fort Collins, CO 80523-1177, USA.
authors.forename: Franck E
authors.initials: FE
authors.lastname: Dayan
authors.affiliation: Institute of Biological Chemistry, Washington State University, Pullman, WA 99164,USA.
authors.forename: David R
authors.initials: DR
authors.lastname: Gang
mesh_terms: D011756:Diphosphates / Q000378:metabolism; D045785:Diterpenes, Clerodane / Q000096:biosynthesis*; D010940:Plant Proteins / Q000235:genetics* / Q000378:metabolism; D027544:Salvia / Q000235:genetics* / Q000378:metabolism*; D059467:Transcriptome
chemical_list: D011756:Diphosphates; D045785:Diterpenes, Clerodane; D010940:Plant Proteins; C090499:salvinorin A
keywords: (–)-kolavenol; (–)-kolavenyl diphosphate; Salvia divinorum; class II diterpene synthase; diterpenoid diversification; neo-clerodane diterpenoid; neo-functionalization; product specificity; repeated evolution; salvinorin A biosynthesis