Characterization And Application Of Guaiene Synthases And Ent-Kaurene Synthases From Stellera Chamaejasme L.

Terpenoids are a group of metabolites which are widely distributed in nature,and synthesized from five-carbon isoprene units.Many plant-derived terpenoids possess various bioacivities and have been used as drugs and functional foods.Stellera chamaejasme L.belongs to Thymelaeaceae.Its dry roots are used as a traditional Chinese medicine herb,named langdu,to treat inflammation,eliminate necrotic tissues and promote the growth of new tissues.It has been reported that its terpenoid constituents(e.g.guaiane-type terpenoids)possess anti-cancer and anti-HIV activity.However,the biosynthesis of these compounds have not been reported yet.The results of this paper are as follows:Form the transcriptome data of S.chamaejasme flowers,five candidate terpene synthase genes(Sch TPS1,Sch TPS15,Sch TPS16,Sch TPS26 and Sch TPS28)were identified;The candidate terpene synthases were characterize by synthetic biology approaches and in vitro enzymatic assays.Sch TPS15,Sch TPS16 and Sch TPS26 are guaiene synthases,Sch TPS1 is ent-kaurene synthase,and Sch TPS28 is an unknown diterpene synthase.A(-)-rotundone-producing microbial platform was constructed for the first time by co-expressing Sch TPS16 and ?-guaiene 2-oxidase Vv STO2 in Saccharomyces cerevisiae.This study paves a way for clarification of biosynthesis of ent-kaurene-and guaiene-type terpenoid constituents in S.chamaejasme,and construction of biosynthetic approaches of these compounds.