15S-lipoxygenase metabolism in the marine diatom Pseudo-nitzschia delicatissima
In recent years, oxylipins (lipoxygenase-derived oxygenated fatty acid products) have been reported in several bloom-forming marine diatoms. Despite increasing attention on the ecophysiological role of these molecules in marine environments, their biosynthesis is largely unknown in these microalgae....
| Veröffentlicht in: | The New phytologist. - 1979. - 183(2009), 4 vom: 01., Seite 1064-1071 |
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| 1. Verfasser: | |
| Weitere Verfasser: | , , , , , , |
| Format: | Online-Aufsatz |
| Sprache: | English |
| Veröffentlicht: |
2009
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| Zugriff auf das übergeordnete Werk: | The New phytologist |
| Schlagworte: | Journal Article 15-oxo-5,9,11,13-pentadecatetraenoic acid Fatty Acids, Unsaturated Oxylipins Eicosapentaenoic Acid AAN7QOV9EA Lipoxygenase EC 1.13.11.12 |
| Zusammenfassung: | In recent years, oxylipins (lipoxygenase-derived oxygenated fatty acid products) have been reported in several bloom-forming marine diatoms. Despite increasing attention on the ecophysiological role of these molecules in marine environments, their biosynthesis is largely unknown in these microalgae. Biochemical methods, including tandem mass spectrometry, nuclear magnetic resonance and radioactive probes were used to identify structures, enzymatic activities and growth-dependent modulation of oxylipin biosynthesis in the pennate diatom Pseudo-nitzschia delicatissima. Three major compounds, 15S-hydroxy-(5Z,8Z,11Z,13E,17Z)-eicosapentaenoic acid (15S-HEPE), 15-oxo-5Z,9E,11E,13E-pentadecatetraenoic acid and 13,14-threo-13R-hydroxy-14S,15S-trans-epoxyeicosa-5Z,8Z,11Z,17Z-tetraenoic acid (13,14-HEpETE), were produced by three putative biochemical pathways triggered by eicosapentaenoic acid-dependent 15S lipoxygenase. Oxylipin production increases along the growth curve, with remarkable changes that precede the demise of the culture. At least one of the compounds, namely 15-oxoacid, is formed only in the stationary phase immediately before the collapse of the culture. Synthesis and regulation of phyco-oxylipins seem to correspond to a signaling mechanism that governs adaptation of diatoms along the growth curve until bloom termination. Factors triggering the process are unknown but synthesis of 15-oxoacid, constrained within a time-window of a few days just before the collapse of the culture, implies the involvement of a physiological control not directly dependent on distress or death of diatom cells |
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| Beschreibung: | Date Completed 02.12.2009 Date Revised 16.04.2021 published: Print-Electronic Citation Status MEDLINE |
| ISSN: | 1469-8137 |
| DOI: | 10.1111/j.1469-8137.2009.02887.x |