Characterization of a Sesquiterpene Synthase Catalyzing Formation of Cedrol and Two Diastereoisomers of Tricho-Acorenol from Euphorbia fischeriana

Abstract

A sesquiterpene synthase gene was identified from the transcriptome of Euphorbia fischeriana Steud, and the function of its product EfTPS12 was characterized by in vitro biochemical experiments and synthetic biology approaches. EfTPS12 catalyzed conversion of farnesyl diphosphate into three products, including cedrol (1) and eupho-acorenols A (2) and B (3) (two diastereoisomers of tricho-acorenol), thereby being named EfCAS herein. The structures of 2 and 3 were determined by spectroscopic methods and comparison of experimental and calculated electronic circular dichroism spectra. EfCAS is the first example of a plant-derived sesquiterpene synthase that is capable of synthesizing acorane-type alcohols. This study also documents that synthetic biology approaches enable large-scale preparation of volatile terpenes and thereby substantially facilitate characterization of corresponding terpene synthases and elucidation of the structures of their products.

Acorane sesquiterpenes from the deep-sea derived Penicillium bilaiae fungus with anti-neuroinflammatory effects

“…In Trichoderma strains, the intermediate B derives tricho-acorenol and relevant analogs as the main components, which are characteristic of cis -orientation of the substituents at C-1 and C-4 ( Aoyagi et al, 2008 ; Citron et al, 2011 ; Li et al, 2011 ; Wu et al, 2011 ; Zhang et al, 2017 ). Eupho-acorenols from a plant are diastereoisomers of tricho-acorenol with trans -orientation of 1,4-substituents, as catalyzed by the sesquiterpene synthase EfTPS12 ( Zhu et al, 2021 ). The stereogenic assembly pattern of acorane sesquiterpene from the plant Lysionotus pauciflorus coincides with those from Trichoderma fungi but in a different manner from that in the plant Daphne genkwa ( Guo et al, 2020 ), which assembles the acorane skeleton through the intermediate C. A basidiomycete (mushroom)-derived acorane-type sesquiterpenoid possesses the scaffold ( Sandargo et al, 2019 ) which is likely constructed by the intermediate A.…”

“…Acrorans in plants are characteristic of the volatile metabolites which play crucial roles as biocontrol and biostimulant agents and are also considered the chemotaxonomic markers of the plant (Zhang et al, 2020). Biogenetically, acrorans are synthesized from farnesyl diphosphate (FPP) as a common precursor by catalysis using sesquiterpene synthases, of which EfCAS in the plant catalyzes the cyclization of FFP to afford a spiro [4.5]decane core such as eupho-acorenols A and B (Zhu et al, 2021). Enzymatic catalysis to generate the acorane core in fungi is also documented (Bian et al, 2018).…”

Identifying Terpenoid Biosynthesis Genes in Euphorbia maculata via Full-Length cDNA Sequencing

“…We found one copy of the sesquiterpene synthase gene in E. maculata . A sesquiterpene synthase gene was isolated from Euphorbia fischeriana , which produced several sesquiterpenoids, including cedrol and eupho-acorenols [ 59 , 60 ]. Oxygenated sesquiterpenes and sesquiterpene hydrocarbons were identified in different Euphorbia species, and their bioactivities were also reported [ 3 ].…”

New Trends and Future Opportunities in the Enzymatic Formation of C−C, C−N, and C−O bonds

“…[72] In 2021, Zi and co-workers reported the discovery of a novel STC which could afford a similar 5,8-bicyclic core. [73] The enzyme was discovered from Euphorbia ficheriana steud, the root of which is used in traditional Chinese medicine for the treatment of edema and tuberculosis. [72,74] The newly discovered enzyme, EfCAS, efficiently catalysed the cyclisation of FPP to cedrol and two tricho-acorenol stereoisomers; eupho-acorenols A and B which were characterised by NMR spectroscopy (Scheme 7B).…”

“…Plant species which have been used throughout history as traditional medicines can also be exploited for discovering new enzymes [72] . In 2021, Zi and co‐workers reported the discovery of a novel STC which could afford a similar 5,8‐bicyclic core [73] . The enzyme was discovered from Euphorbia ficheriana steud, the root of which is used in traditional Chinese medicine for the treatment of edema and tuberculosis [72,74] .…”