Cynara cardunculus (Asteraceae) is a cross pollinated perennial crop which includes the two cultivatedtaxa globe artichoke and cultivated cardoon. The leaves of these plants contain high concentrationsof sesquiterpene lactones (STLs) among which cynaropicrin is the most represented, and has recentlyattracted attention because of its therapeutic potential as anti-tumor and anti-photoaging agent. Costuno-lide is considered the common precursor of the STLs and three enzymes are involved in its biosyntheticpathway: i.e. the germacrene A synthase (GAS), the germacrene A oxidase (GAO) and the costunolidesynthase (COS). Here we report on the isolation of two P450 genes, (i.e. CYP71AV9 and CYP71BL5), ina set of ~19,000 C. cardunculus unigenes, and their functional characterization in yeast and in planta.The metabolite analyses revealed that the co-expression of CYP71AV9 together with GAS resulted in thebiosynthesis of germacra-1(10),4,11(13)-trien-12-oic acid in yeast. The co-expression of CYP71BL5 andCYP71AV9 with GAS led to biosynthesis of the free costunolide in yeast and costunolide conjugates inNicotiana benthamiana, demonstrating their involvement in STL biosynthesis as GAO and COS enzymes.The substrate specificity of CYP71AV9 was investigated by testing its ability to convert amorpha-4,11-diene, (+)-germacrene D and cascarilladiene to their oxidized products when co-expressed in yeast withthe corresponding terpene synthases.
- artichoke leaf extract
- globe artichoke
- scolymus l.
- yeast expression
Eljounaidi, K., Cankar, K., Comino, C., Moglia, A., Hehn, A., Bourgaud, F., Bouwmeester, H. J., Menin, B., Lanteri, S., & Beekwilder, M. J. (2014). Cytochrome P450s from Cynara cardunculus L. CYP71AV9 andCYP71BL5, catalyze distinct hydroxylations in the sesquiterpenelactone biosynthetic pathway. Plant Science, 223, 59-68. https://doi.org/10.1016/j.plantsci.2014.03.007