In this paper we provide evidence for the presence of a de novo route for myo-inositol biosynthesis in the protozoan parasite Leishmania donovani, by the application of 13C labelling and electrospray ionisation mass spectrometry (ESMS). For this myo-[1-13C] inositol is prepared from D-[6-13C] glucose and biosynthetically incorporated in the parasite promastigote cell culture. Biosynthetic phosphatidylinositol (PI) and its hydrolysis products ...