Jasmonates (JAs) are plant hormones that integrate external stress stimuli with physiological responses. (+)-7-iso-JA-L-Ile is the natural JA ligand of COI1, a component of a known JA receptor. The upstream JA biosynthetic precursor cis-(+)-12-oxo-phytodienoic acid (cis-(+)-OPDA) has been reported to act independently of COI1 as an essential signal in several stress-induced and developmental processes. Wound-induced increases in the endogenous levels of JA/JA-Ile are accompanied by two to tenfold increases in the concentration of OPDA, but its means of perception and metabolism are unknown. To screen for putative OPDA metabolites, vegetative tissues of flowering Arabidopsis thaliana were extracted with 25% aqueous methanol (v/v), purified by single-step reversed-phase polymer-based solid-phase extraction, and analyzed by high throughput mass spectrometry. This enabled the detection and quantitation of a low abundant OPDA analog of the biologically active (+)-7-iso-JA-L-Ile in plant tissue samples. Levels of the newly identified compound and the related phytohormones JA, JA-Ile and cis-(+)-OPDA were monitored in wounded leaves of flowering Arabidopsis lines (Col-0 and Ws) and compared to the levels observed in Arabidopsis mutants deficient in the biosynthesis of JA (dde2-2, opr3) and JA-Ile (jar1). The observed cis-(+)-OPDA-Ile levels varied widely, raising questions concerning its role in Arabidopsis stress responses.
- MeSH
- Arabidopsis chemie MeSH
- cyklopentany chemie izolace a purifikace MeSH
- diazoniové sloučeniny MeSH
- isoleucin analogy a deriváty chemie MeSH
- květy chemie MeSH
- listy rostlin metabolismus MeSH
- nenasycené mastné kyseliny chemie izolace a purifikace metabolismus MeSH
- oxylipiny chemie izolace a purifikace MeSH
- pyridiny MeSH
- regulátory růstu rostlin metabolismus MeSH
- stereoizomerie MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
High performance countercurrent chromatography (HPCCC) was successfully applied for the separation of nostotrebin 6 from cultivated soil cyanobacteria in a two-step operation. A two-phase solvent system composed of n-hexane-ethyl acetate-methanol-water (4:5:4:5, v/v/v/v) was employed for the HPCCC separation. In the first-step operation, its neutral upper phase was used as stationary phase and its basic lower phase (1% NH3 in lower phase) was employed as mobile phase at a flow rate of 1 mL/min. In the second operation step, its neutral upper phase was used as stationary phase, whereas both its neutral lower phase and basic lower phase were employed as mobile phase with a linear gradient elution at a flow rate of 0.8 mL/min. The revolution speed and temperature of the separation column were 1,000 rpm and 30 °C, respectively. Using HPCCC followed by clean-up on Sephadex LH-20 gel, 4 mg of nostotrebin 6 with a purity of 99% as determined by HPLC/DAD-ESI-HRMS was obtained from 100 mg of crude extract. The chemical identity of the isolated compound was confirmed by comparing its spectroscopic data (UV, ESI-HRMS, ESI-HRMS2) with those of an authentic standard and data available in the literature.
- MeSH
- acetáty chemie MeSH
- cholinesterasové inhibitory chemie izolace a purifikace MeSH
- cyklopentany chemie izolace a purifikace MeSH
- hexany chemie MeSH
- hmotnostní spektrometrie s elektrosprejovou ionizací MeSH
- methanol chemie MeSH
- Nostoc chemie MeSH
- protiproudá chromatografie MeSH
- půdní mikrobiologie MeSH
- rozpouštědla chemie MeSH
- voda chemie MeSH
- vysokoúčinná kapalinová chromatografie MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
Nostotrebin 6, a new polyphenolic compound with a fully substituted 2,2'-bis(cyclopent-4-en-1,3-dione) skeleton, was isolated from a methanolic extract of the cyanobacterial strain Nostoc sp. str. Lukesová 27/97. The structure of this compound was determined using X-ray crystallography and further supported by NMR, IR spectroscopy, and MS. Nostotrebin 6 is an S-parabolic I-parabolic noncompetitive inhibitor of acetylcholinesterase (IC(50) = 5.5 microM) and an S-parabolic I-parabolic mixed inhibitor of butyrylcholinesterase (IC(50) = 6.1-7.5 microM). The inhibitory potency of nostotrebin 6 was compared with that of tacrine and galanthamine.
- MeSH
- acetylcholinesterasa účinky léků MeSH
- butyrylcholinesterasa účinky léků MeSH
- cholinesterasové inhibitory chemie izolace a purifikace farmakologie MeSH
- cyklopentany chemie izolace a purifikace farmakologie MeSH
- inhibiční koncentrace 50 MeSH
- lidé MeSH
- molekulární struktura MeSH
- Nostoc chemie MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
