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Identification of the Optimal Light Harvesting Antenna Size for High-Light Stress Mitigation in Plants

One of the major constraints limiting biomass production in autotrophs is the low thermodynamic efficiency of photosynthesis, ranging from 1 to 4%. Given the absorption spectrum of photosynthetic pigments and the spectral distribution of sunlight, photosynthetic efficiencies as high as 11% are possi...

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Autores principales: Wu, Guangxi, Ma, Lin, Sayre, Richard T., Lee, Choon-Hwan
Formato: Online Artículo Texto
Lenguaje:English
Publicado: Frontiers Media S.A. 2020
Materias:
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7243658/
https://www.ncbi.nlm.nih.gov/pubmed/32499795
http://dx.doi.org/10.3389/fpls.2020.00505
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author Wu, Guangxi
Ma, Lin
Sayre, Richard T.
Lee, Choon-Hwan
author_facet Wu, Guangxi
Ma, Lin
Sayre, Richard T.
Lee, Choon-Hwan
author_sort Wu, Guangxi
collection PubMed
description One of the major constraints limiting biomass production in autotrophs is the low thermodynamic efficiency of photosynthesis, ranging from 1 to 4%. Given the absorption spectrum of photosynthetic pigments and the spectral distribution of sunlight, photosynthetic efficiencies as high as 11% are possible. It is well-recognized that the greatest thermodynamic inefficiencies in photosynthesis are associated with light absorption and conversion of excited states into chemical energy. This is due to the fact that photosynthesis light saturates at one quarter full sunlight intensity in plants resulting in the dissipation of excess energy as heat, fluorescence and through the production of damaging reactive oxygen species. Recently, it has been demonstrated that it is possible to adjust the size of the light harvesting antenna over a broad range of optical cross sections through targeted reductions in chlorophyll b content, selectively resulting in reductions of the peripheral light harvesting antenna size, especially in the content of Lhcb3 and Lhcb6. We have examined the impact of alterations in light harvesting antenna size on the amplitude of photoprotective activity and the evolutionary fitness or seed production in Camelina grown at super-saturating and sub-saturating light intensities to gain an understanding of the driving forces that lead to the selection for light harvesting antenna sizes best fit for a range of light intensities. We demonstrate that plants having light harvesting antenna sizes engineered for the greatest photosynthetic efficiency also have the greatest capacity to mitigate high light stress through non-photochemical quenching and reduction of reactive oxygen associated damage. Under sub-saturating growth light intensities, we demonstrate that the optimal light harvesting antenna size for photosynthesis and seed production is larger than that for plants grown at super-saturating light intensities and is more similar to the antenna size of wild-type plants. These results suggest that the light harvesting antenna size of plants is designed to maximize fitness under low light conditions such as occurs in shaded environments and in light competition with other plants.
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spelling pubmed-72436582020-06-03 Identification of the Optimal Light Harvesting Antenna Size for High-Light Stress Mitigation in Plants Wu, Guangxi Ma, Lin Sayre, Richard T. Lee, Choon-Hwan Front Plant Sci Plant Science One of the major constraints limiting biomass production in autotrophs is the low thermodynamic efficiency of photosynthesis, ranging from 1 to 4%. Given the absorption spectrum of photosynthetic pigments and the spectral distribution of sunlight, photosynthetic efficiencies as high as 11% are possible. It is well-recognized that the greatest thermodynamic inefficiencies in photosynthesis are associated with light absorption and conversion of excited states into chemical energy. This is due to the fact that photosynthesis light saturates at one quarter full sunlight intensity in plants resulting in the dissipation of excess energy as heat, fluorescence and through the production of damaging reactive oxygen species. Recently, it has been demonstrated that it is possible to adjust the size of the light harvesting antenna over a broad range of optical cross sections through targeted reductions in chlorophyll b content, selectively resulting in reductions of the peripheral light harvesting antenna size, especially in the content of Lhcb3 and Lhcb6. We have examined the impact of alterations in light harvesting antenna size on the amplitude of photoprotective activity and the evolutionary fitness or seed production in Camelina grown at super-saturating and sub-saturating light intensities to gain an understanding of the driving forces that lead to the selection for light harvesting antenna sizes best fit for a range of light intensities. We demonstrate that plants having light harvesting antenna sizes engineered for the greatest photosynthetic efficiency also have the greatest capacity to mitigate high light stress through non-photochemical quenching and reduction of reactive oxygen associated damage. Under sub-saturating growth light intensities, we demonstrate that the optimal light harvesting antenna size for photosynthesis and seed production is larger than that for plants grown at super-saturating light intensities and is more similar to the antenna size of wild-type plants. These results suggest that the light harvesting antenna size of plants is designed to maximize fitness under low light conditions such as occurs in shaded environments and in light competition with other plants. Frontiers Media S.A. 2020-05-15 /pmc/articles/PMC7243658/ /pubmed/32499795 http://dx.doi.org/10.3389/fpls.2020.00505 Text en Copyright © 2020 Wu, Ma, Sayre and Lee. http://creativecommons.org/licenses/by/4.0/ This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) and the copyright owner(s) are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms.
spellingShingle Plant Science
Wu, Guangxi
Ma, Lin
Sayre, Richard T.
Lee, Choon-Hwan
Identification of the Optimal Light Harvesting Antenna Size for High-Light Stress Mitigation in Plants
title Identification of the Optimal Light Harvesting Antenna Size for High-Light Stress Mitigation in Plants
title_full Identification of the Optimal Light Harvesting Antenna Size for High-Light Stress Mitigation in Plants
title_fullStr Identification of the Optimal Light Harvesting Antenna Size for High-Light Stress Mitigation in Plants
title_full_unstemmed Identification of the Optimal Light Harvesting Antenna Size for High-Light Stress Mitigation in Plants
title_short Identification of the Optimal Light Harvesting Antenna Size for High-Light Stress Mitigation in Plants
title_sort identification of the optimal light harvesting antenna size for high-light stress mitigation in plants
topic Plant Science
url https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7243658/
https://www.ncbi.nlm.nih.gov/pubmed/32499795
http://dx.doi.org/10.3389/fpls.2020.00505
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