Tryptophan is a precursor for melatonin and serotonin biosynthesis in in vitro regenerated St. John's wort (Hypericum perforatum L. cv. Anthos) plants |
| |
Authors: | S J Murch S KrishnaRaj P K Saxena |
| |
Institution: | (1) Department of Plant Agriculture, Biotechnology Division, Edmund C. Bovey Complex, University of Guelph, Guelph, Ontario, Canada, N1G 2W1 Fax: +1-519-7670755 e-mail psaxena@uoguelph.ca, CA |
| |
Abstract: | Hypericum perforatum cv. Anthos) is presented. Isotope tracer experiments were performed on plantlets regenerated from thidiazuron-induced stem
explants and grown on MS basal medium for 2 months. Radiolabel from 14C-tryptophan was recovered as 14C-indoleacetic acid, 14C-tryptamine, 14C-5-hydroxytryptophan, 14C-serotonin and 14C-melatonin in the treated St. John's wort plantlets. Chromatographic peak identity was confirmed by high performance liquid
chromatography-mass spectrometry-mass spectrometry and quantification of melatonin by radioimmunoassay. Significantly more
radiolabel was recovered in serotonin relative to melatonin under low light conditions with this ratio being reversed under
increased lighting, indicating that the rate of flow through this biosynthetic pathway is regulated, at least in part, by
light.
Received: 9 November 1999 / Revision received: 16 December 1999 / Accepted: 21 December 1999 |
| |
Keywords: | Tryptophan Indoleacetic acid Melatonin Serotonin St John's wort |
本文献已被 SpringerLink 等数据库收录! |
|