started in Jan 2011 Analytical characterization of the biosynthesis of nudicaulins in Papaver nudicaule Friedrich-Schiller-Universität Jena, Chemisch-Geowissenschaftliche Fakultät First Supervisor: Dr. B. Schneider Co-Supervisor(s): Dr. E. Tatsis, Prof. Dr. J. Einax (Friedrich Schiller Universität Jena)
The color of the flower plays a crucial role in the interaction between plants and their pollinators. The main chromophoric substances of the yellow flowers of P. nudicaule are nudicaulins. The chemical structure of the nudicaulin agylcone is unique among the flower pigments and the biosynthesis is still obscure. The structure suggested formation from a chalcone-related moiety and an indole-type precursor.Retrobiosynthetic studies with 13CO2 demonstrated that the indole part comes from the indole/tryptophan pathway and polyphenolic part is derived from the flavonoid pathway.
To investigate the biosynthesis of this indole alkaloid in detail, feeding experiments with 13C-labelled precursors, such as glucose, phenylalanine, malonic acid, acetic acid, indole, tryptophan, anthranilic acid and ribose, are performed. After isolation and chromatographic separation, the nudicaulins are analyzed by NMR spectroscopy and mass spectrometry to reveal 13C incorporation and to establish biosynthetic precursor-product relationships.