Gregory L Fisher oral presentation (OA2-Mon3-3-1)
Elucidation of Natural Product Biosynthesis in Amazonian Sextonia rubra via 100 nm-Scale TOF-SIMS Tandem MS Imaging
1 Physical Electronics, 18725 Lake Drive East, MN 55317 Chanhassen, United States
2 Institut de Chimie des Substances Naturelles - CNRS, Avenue de la Terrasse, 91190 Gif-sur-Yvette, France
3 Institut de Physique Nucléaire - CNRS, rue Georges CLEMENCEAU, 91406 Orsay, France
4 UMR EcoFoG, AgroParisTech, Cirad, INRA - CNRS, Avenue Pasteur, 97306 Cayenne, France
5 UMR EcoFoG, AgroParisTech, INRA - CNRS, Campus Agronomique, 97397 Kourou, France
We have explored the botanical synthesis of bioactive molecules in the wood of S. rubra (Figure 1) via TOF-SIMS Parallel Imaging MS/MS. This investigation is part of an effort to develop a new strategy for investigating natural product formation in relation to the secondary metabolite synthesis during heartwood formation. The TOF-TOF tandem mass spectrometer of the PHI nanoTOF II enabled, for the first time in this field of study, simultaneous surface screening of the botanical matrix chemistry by TOF-SIMS (MS1) imaging and targeted identification of biosynthetic components by MS/MS (MS2) imaging . Imaging of molecules with unambiguous identification occurred in minutes without observable degradation of the specimen. Hence, the wood chemistry was broadly profiled while multiple tandem MS imaging analyses were performed for discovery.
The metabolites of rubrynolide and rubrenolide, having significant xylophage toxicity and antifungal properties , are produced in oil cells that are found in close proximity to both vessels and parenchyma cells. Moreover, there are thought to be several bio-molecular precursors en route to these bioactive metabolites. Our goal was to identify biosynthetic precursors, and to verify their coincidence with rubrynolide and rubrenolide, via tandem MS imaging. We were able to demonstrate the presence of numerous precursors and to confirm or derive their structure using the tandem MS product ion spectrum, thus contributing in the exploration of natural product biosynthesis.