Biosynthesis of germacrene A carboxylic acid in chicory roots. Demonstration of a cytochrome P450 (+)-germacrene A hydroxylase and NADP+-dependent sesquiterpenoid dehydrogenase(s) involved in sesquiterpene lactone biosynthesis. - de Kraker,J.-W..; Franssen,M..C..R..; Dalm,M..C..F..; de Groot,A..; Bouwmeester,H..J.. (Plant Physiology, 2001)