Biosynthesis of Sesquiterpene Lactones in Pyrethrum (Tanacetum cinerariifolium)
Figure 8
α-costic acid and γ-costic acid production in yeast.
A, GC-MS chromatograms for the terpenoids with a parent mass of m/s 234 isolated from yeast transformed with the indicated genes. Front line showing the metabolites for the empty vector control, middle line showing the metabolites of yeast transformed with TcGAS and TcGAO, and last line showing the metabolites of yeast transformed with Tanacetum parthenium TpGAS and Cichorium intybus CiGAO. B, mass fragmentation pattern of peak 1 (1a), α-costic acid (1b), peak 2 (2a), and γ-costic acid (2b). C, acid induced rearrangement of germacrene A acid to α-costic acid and γ-costic acid.