Three distinct biochemical subtypes of C4 photosynthesis? A modelling analysis
© The Author 2014. Published by Oxford University Press on behalf of the Society for Experimental Biology.
| Veröffentlicht in: | Journal of experimental botany. - 1985. - 65(2014), 13 vom: 21. Juli, Seite 3567-78 |
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| Weitere Verfasser: | , , |
| Format: | Online-Aufsatz |
| Sprache: | English |
| Veröffentlicht: |
2014
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| Zugriff auf das übergeordnete Werk: | Journal of experimental botany |
| Schlagworte: | Journal Article Research Support, Non-U.S. Gov't Research Support, U.S. Gov't, Non-P.H.S. Efficiency NAD-ME NADP-ME PEPCK. flexibility mixture Plant Proteins mehr... |
| Zusammenfassung: | © The Author 2014. Published by Oxford University Press on behalf of the Society for Experimental Biology. C4 photosynthesis has higher light-use, nitrogen-use, and water-use efficiencies than C3 photosynthesis. Historically, most of C4 plants were classified into three subtypes (NADP-malic enzyme (ME), NAD-ME, or phosphoenolpyruvate carboxykinase (PEPCK) subtypes) according to their major decarboxylation enzyme. However, a wealth of historic and recent data indicates that flexibility exists between different decarboxylation pathways in many C4 species, and this flexibility might be controlled by developmental and environmental cues. This work used systems modelling to theoretically explore the significance of flexibility in decarboxylation mechanisms and transfer acids utilization. The results indicate that employing mixed C4 pathways, either the NADP-ME type with the PEPCK type or the NAD-ME type with the PEPCK type, effectively decreases the need to maintain high concentrations and concentration gradients of transport metabolites. Further, maintaining a mixture of C4 pathways robustly affords high photosynthetic efficiency under a broad range of light regimes. A pure PEPCK-type C4 photosynthesis is not beneficial because the energy requirements in bundle sheath cells cannot be fulfilled due to them being shaded by mesophyll cells. Therefore, only two C4 subtypes should be considered as distinct subtypes, the NADP-ME type and NAD-ME types, which both inherently involve a supplementary PEPCK cycle |
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| Beschreibung: | Date Completed 26.02.2015 Date Revised 21.03.2024 published: Print-Electronic Citation Status MEDLINE |
| ISSN: | 1460-2431 |
| DOI: | 10.1093/jxb/eru058 |