Table of Contents
Journal of Amino Acids
Volume 2010, Article ID 265069, 7 pages
Research Article

Fluorine-Tagged 5-Hydroxytryptophan to Investigate Amino Acid Metabolism In Vivo

1Marist College, 3399 North Road, Poughkeepsie, NY 12601, USA
2Inovatia Laboratories, LLC, P.O. Box 30, Fayette, MO 65248-0030, USA

Received 1 October 2009; Accepted 17 February 2010

Academic Editor: Carlo Chiarla

Copyright © 2010 Zofia E. Gagnon et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.


Auxin a plant growth hormone, has a metabolic pathway that includes molecules and enzymes like those in animal brains. In this study, tomato plant seedlings (Lycopersicon esculenta) were used to investigate the fate of fluorine-tagged 5-hydroxytryptophan (PF-5-HTP) being developed for fluorine spectroscopy and imaging. Seedlings were treated with high or low concentrations of 5-HTP or PF-5-HTP and compared with controls. Metabolites of the PF-5-HTP were quantified using a custom immunoassay for the tag. Serotonin (5-HT) levels were measured with spectrofluorometry and thin-layer chromatography. Plants in treatment conditions had serotonin levels five to six times higher than controls. PF-5-HTP served as a precursor for serotonin in a biosynthetic pathway in this plant model, providing evidence for the bioavailability of the novel molecule. The increase in serotonin in plants grown in media culture supplemented with 5-HTP or PF-5-HTP might have useful applications in pharmacology.