A novel multifunctional triterpene synthase from Arabidopsis thaliana

The Arabidopsis thaliana genome sequencing project has identified several triterpene synthase homologues. One cDNA of these clones, YUP8H12R.43, was obtained and functionally expressed in yeast. At least nine triterpenes have been identified as its products based on NMR and LCMS analysis. The products include extensively migrated triterpenes, multiflorenol and bauerenol. Several chimeric clones were constructed between YUP8H12R.43 and A. thaliana lupeol synthase LUP1, to reveal that a C-terminal half and a part of N-terminus is important for such product multiplicity. The presence of such multifunctional triterpene synthase in plants is noteworthy from both a mechanistic and a physiological point of view.