Chronic exposure of soybean plants to nanomolar cadmium reveals specific additional high-affinity targets of cadmium toxicity
© The Author(s) 2019. Published by Oxford University Press on behalf of the Society for Experimental Biology. All rights reserved. For permissions, please email: journals.permissionsoup.com.
| Veröffentlicht in: | Journal of experimental botany. - 1985. - 71(2020), 4 vom: 19. Feb., Seite 1628-1644 |
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| 1. Verfasser: | |
| Weitere Verfasser: | , , , , , , |
| Format: | Online-Aufsatz |
| Sprache: | English |
| Veröffentlicht: |
2020
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| Zugriff auf das übergeordnete Werk: | Journal of experimental botany |
| Schlagworte: | Journal Article Research Support, Non-U.S. Gov't Cadmium XANES lipidomics metabolomics metal stress metalloproteomics soybean (Glycine max) sublethal toxicity mehr... |
| Zusammenfassung: | © The Author(s) 2019. Published by Oxford University Press on behalf of the Society for Experimental Biology. All rights reserved. For permissions, please email: journals.permissionsoup.com. Solving the global environmental and agricultural problem of chronic low-level cadmium (Cd) exposure requires better mechanistic understanding. Here, soybean (Glycine max) plants were exposed to Cd concentrations ranging from 0.5 nM (background concentration, control) to 3 µM. Plants were cultivated hydroponically under non-nodulating conditions for 10 weeks. Toxicity symptoms, net photosynthetic oxygen production and photosynthesis biophysics (chlorophyll fluorescence: Kautsky and OJIP) were measured in young mature leaves. Cd binding to proteins [metalloproteomics by HPLC-inductively coupled plasma (ICP)-MS] and Cd ligands in light-harvesting complex II (LHCII) [X-ray absorption near edge structure (XANES)], and accumulation of elements, chloropyll, and metabolites were determined in leaves after harvest. A distinct threshold concentration of toxicity onset (140 nM) was apparent in strongly decreased growth, the switch-like pattern for nutrient uptake and metal accumulation, and photosynthetic fluorescence parameters such as Φ RE10 (OJIP) and saturation of the net photosynthetic oxygen release rate. XANES analyses of isolated LHCII revealed that Cd was bound to nitrogen or oxygen (and not sulfur) atoms. Nutrient deficiencies caused by inhibited uptake could be due to transporter blockage by Cd ions. The changes in specific fluorescence kinetic parameters indicate electrons not being transferred from PSII to PSI. Inhibition of photosynthesis combined with inhibition of root function could explain why amino acid and carbohydrate metabolism decreased in favour of molecules involved in Cd stress tolerance (e.g. antioxidative system and detoxifying ligands) |
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| Beschreibung: | Date Completed 14.05.2021 Date Revised 19.09.2024 published: Print Citation Status MEDLINE |
| ISSN: | 1460-2431 |
| DOI: | 10.1093/jxb/erz530 |