tuberonic-acid-glucoside and jasmonic-acid

In this study, a CE-MS method has been developed to carry out the qualitative characterization of a lemon verbena (Lippia citriodora) extract for the first time. The CE and ESI-MS parameters were optimized with respect to resolution, analysis time and peak shape in order to maximize the number of compounds detected and the sensitivity of their determination. The use of two different MS analyzers, TOF-MS and IT-MS, enabled the tentative identification of the major components of this extract. Thus, using this method, 16 compounds were determined. Some of them have been previously identified by HPLC methods, although four compounds were also found for the first time in lemon verbena such as asperuloside, tuberonic acid glucoside or 5'-hydroxyjasmonic acid 5'-O-glucoside, shanzhiside and ixoside. These results demonstrate that CE-MS generates data complementary to those obtainable by HPLC-MS and it is particularly suited to the analysis of plant metabolites.

Topics: Chromatography, High Pressure Liquid; Cyclopentane Monoterpenes; Cyclopentanes; Electrophoresis, Capillary; Glucosides; Lippia; Molecular Structure; Oxylipins; Phenols; Plant Extracts; Plant Growth Regulators; Pyrans; Spectrometry, Mass, Electrospray Ionization

Tuberonic acid (TA) and its glucoside (TAG) have been isolated from potato (Solanum tuberosum L.) leaflets and shown to exhibit tuber-inducing properties. These compounds were reported to be biosynthesized from jasmonic acid (JA) by hydroxylation and subsequent glycosylation, and to be contained in various plant species. Here we describe the in vivo hydrolytic activity of TAG in rice. In this study, the TA resulting from TAG was not converted into JA. Tuberonic acid glucoside (TAG)-hydrolyzing beta-glucosidase, designated OsTAGG1, was purified from rice by six purification steps with an approximately 4300-fold purification. The purified enzyme migrated as a single band on native PAGE, but as two bands with molecular masses of 42 and 26 kDa on SDS-PAGE. Results from N-terminal sequencing and peptide mass fingerprinting of both polypeptides suggested that both bands were derived from a single polypeptide, which is a member of the glycosyl hydrolase family 1. In the native enzyme, the K(m) and V(max) values of TAG were 31.7 microM and 0.25 microkatal/mg protein, OsTAGG1 preferentially hydrolyzed TAG and methyl TAG. Here we report that OsTAGG1 is a specific beta-glucosidase hydrolyzing TAG, which releases the physiologically active TA.

Topics: Acetates; beta-Glucosidase; Cyclopentanes; Electrophoresis, Polyacrylamide Gel; Glucosides; Glycosylation; Hydrolysis; Molecular Structure; Oryza; Oxylipins; Peptide Mapping; Plant Leaves; Plant Tubers; Plants; Solanum tuberosum

In the current study, we investigated the influences of theobroxide on stem elongation in spinach (Spinacia oleracea). Our results showed that stem elongation and flower formation were inhibited by spraying spinach plants with theobroxide under inductive, long day conditions (16 h light/8 h dark), while application of exogenous applied GA3 prevented the effect of theobroxide. Quantitative analysis showed that theobroxide suppressed GA1 biosynthesis, whereas the endogenous content of jasmonic acid was unchanged. However, under short day conditions (10 h light/14 h dark), there were no differences in stem length between treated and untreated plants. These results suggest that the inhibition of stem elongation by theobroxide is probably due to the suppression of gibberellin biosynthesis.

Topics: Acetates; Ascomycota; Cyclohexanes; Cyclopentanes; Epoxy Compounds; Flowers; Gibberellins; Glucosides; Light; Oxylipins; Plant Stems; Spinacia oleracea

The metabolism of deuterium-labeled (+/-)-jasmonicacid and 3-oxo-2-[(Z)pent-2'-enyl]-cyclopentan-1- octanoic acid in potato (Solanum tuberosum L.) was examined by using cultures of potato single-node stems. Deuterium-labeled (+/-)-jasmonic acid and 3-oxo-2-[(Z) pent-2'-enyl]cyclopentan-1-octanoic acid, which had been prepared from commercially available methyl (+/-)-jasmonate, were fed to the cultures, and the metabolites were extracted from the plants and analyzed by a liquid chromatography-selected ion monitoring system. The metabolism of deuterium-labeled (+/-)-jasmonic acid and 3-oxo-2-[(Z)-2'-pentenyl]cyclopentan-1-octanoic acid to 5' and 4'-O-glucopyranosyloxyjasmoic acids was strongly suggested.

Topics: Acetates; Caprylates; Chromatography, Liquid; Culture Techniques; Cyclopentanes; Deuterium; Glucosides; Glycosylation; Isotope Labeling; Molecular Structure; Oxylipins; Plant Stems; Solanum tuberosum; Stereoisomerism