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Li A, You T, Pang X, Wang Y, Tian L, Li X, Liu Z. Structural basis for an early stage of the photosystem II repair cycle in Chlamydomonas reinhardtii. Nat Commun 2024; 15:5211. [PMID: 38890314 PMCID: PMC11189392 DOI: 10.1038/s41467-024-49532-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2023] [Accepted: 06/10/2024] [Indexed: 06/20/2024] Open
Abstract
Photosystem II (PSII) catalyzes water oxidation and plastoquinone reduction by utilizing light energy. It is highly susceptible to photodamage under high-light conditions and the damaged PSII needs to be restored through a process known as the PSII repair cycle. The detailed molecular mechanism underlying the PSII repair process remains mostly elusive. Here, we report biochemical and structural features of a PSII-repair intermediate complex, likely arrested at an early stage of the PSII repair process in the green alga Chlamydomonas reinhardtii. The complex contains three protein factors associated with a damaged PSII core, namely Thylakoid Enriched Factor 14 (TEF14), Photosystem II Repair Factor 1 (PRF1), and Photosystem II Repair Factor 2 (PRF2). TEF14, PRF1 and PRF2 may facilitate the release of the manganese-stabilizing protein PsbO, disassembly of peripheral light-harvesting complexes from PSII and blockage of the QB site, respectively. Moreover, an α-tocopherol quinone molecule is located adjacent to the heme group of cytochrome b559, potentially fulfilling a photoprotective role by preventing the generation of reactive oxygen species.
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Affiliation(s)
- Anjie Li
- Key Laboratory of Biomacromolecules (CAS), National Laboratory of Biomacromolecules, CAS Centre for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing, 100101, China
- College of Life Sciences, University of Chinese Academy of Sciences, Beijing, 101408, China
| | - Tingting You
- Key Laboratory of Growth Regulation and Translational Research of Zhejiang Province, School of Life Sciences, Westlake University, Hangzhou, 310024, China
| | - Xiaojie Pang
- College of Life Sciences, University of Chinese Academy of Sciences, Beijing, 101408, China
- Key Laboratory of Photobiology, Institute of Botany, Chinese Academy of Sciences, Beijing, 100093, China
| | - Yidi Wang
- Key Laboratory of Biomacromolecules (CAS), National Laboratory of Biomacromolecules, CAS Centre for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing, 100101, China
- College of Life Sciences, University of Chinese Academy of Sciences, Beijing, 101408, China
| | - Lijin Tian
- College of Life Sciences, University of Chinese Academy of Sciences, Beijing, 101408, China
- Key Laboratory of Photobiology, Institute of Botany, Chinese Academy of Sciences, Beijing, 100093, China
| | - Xiaobo Li
- Key Laboratory of Growth Regulation and Translational Research of Zhejiang Province, School of Life Sciences, Westlake University, Hangzhou, 310024, China.
- Institute of Biology, Westlake Institute for Advanced Study, Hangzhou, 310024, China.
| | - Zhenfeng Liu
- Key Laboratory of Biomacromolecules (CAS), National Laboratory of Biomacromolecules, CAS Centre for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing, 100101, China.
- College of Life Sciences, University of Chinese Academy of Sciences, Beijing, 101408, China.
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Li M, Wang S, Song Y, Chen L. A fluorescent covalent organic framework for visual detection of p-benzoquinone. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2023; 286:122022. [PMID: 36308832 DOI: 10.1016/j.saa.2022.122022] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/25/2022] [Revised: 09/30/2022] [Accepted: 10/17/2022] [Indexed: 06/16/2023]
Abstract
P-benzoquinone (PBQ) is toxic and harmful for health. The development of portable sensor to realize the detection of PBQ is of great significance. Herein, a novel covalent organic framework (COFML-TFPB) with intramolecular charge transfer and aggregation induced emission properties was proposed via condensation reaction of melem (ML) and 1,3,5-tris (4-formylphenyl) benzene (TFPB). COFML-TFPB shows strong fluorescence in both solution and solid state and can be used for the fluorescence detection of PBQ. Due to the internal filtration effect and photoinduced electron transfer effect, PBQ can quench the fluorescence of COFML-TFPB. The developed COFML-TFPB fluorescent sensor displayed a wide linear range for PBQ from 0.138 ng mL-1 - 35 μg mL-1, and the detection limit was 0.046 ng mL-1. In addition, fluorescent test paper for rapid and portable detection of PBQ was also developed by depositing COFML-TFPB on filter paper directly. It reduces the cost and time of detection and realizes the semiquantitative detection of PBQ. Moreover, the fluorescence color was converted into digital RGB value to calculate the concentration of PBQ accurately by a smartphone. This method realizes the portable qualitative and semiquantitative determination of PBQ.
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Affiliation(s)
- Mengyao Li
- National Engineering Research Center for Carbohydrate Synthesis/Key Lab of Fluorine, Silicon for Energy Materials and Chemistry of Ministry of Education, College of Chemistry and Chemical Engineering, Jiangxi Normal University, 99 Ziyang Avenue, Nanchang 330022, China
| | - Shiqi Wang
- National Engineering Research Center for Carbohydrate Synthesis/Key Lab of Fluorine, Silicon for Energy Materials and Chemistry of Ministry of Education, College of Chemistry and Chemical Engineering, Jiangxi Normal University, 99 Ziyang Avenue, Nanchang 330022, China
| | - Yonghai Song
- National Engineering Research Center for Carbohydrate Synthesis/Key Lab of Fluorine, Silicon for Energy Materials and Chemistry of Ministry of Education, College of Chemistry and Chemical Engineering, Jiangxi Normal University, 99 Ziyang Avenue, Nanchang 330022, China
| | - Lili Chen
- National Engineering Research Center for Carbohydrate Synthesis/Key Lab of Fluorine, Silicon for Energy Materials and Chemistry of Ministry of Education, College of Chemistry and Chemical Engineering, Jiangxi Normal University, 99 Ziyang Avenue, Nanchang 330022, China.
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3
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Souza CS, Daood H, Duah SA, Vinogradov S, Palotás G, Neményi A, Helyes L, Pék Z. Stability of carotenoids, carotenoid esters, tocopherols and capsaicinoids in new chili pepper hybrids during natural and thermal drying. Lebensm Wiss Technol 2022. [DOI: 10.1016/j.lwt.2022.113520] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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4
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Content and response to Ɣ-irradiation before over-ripening of capsaicinoid, carotenoid, and tocopherol in new hybrids of spice chili peppers. Lebensm Wiss Technol 2021. [DOI: 10.1016/j.lwt.2021.111555] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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5
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Kruk J, Szymańska R. Singlet oxygen oxidation products of carotenoids, fatty acids and phenolic prenyllipids. JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY B-BIOLOGY 2021; 216:112148. [PMID: 33556703 DOI: 10.1016/j.jphotobiol.2021.112148] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/19/2020] [Revised: 12/27/2020] [Accepted: 01/28/2021] [Indexed: 10/22/2022]
Abstract
Singlet oxygen (1O2) is the major reactive oxygen species ROS causing photooxidative stress in plants which is formed predominantly in the reaction center of photosystem II during photosynthesis. To avoid deleterious effects of 1O2 oxygen on photosynthetic membrane components, plant synthesize a variety of 1O2 quenchers of lipophilic character, such as carotenoids or phenolic prenyllipids (tocopherols, plastochromanol-8, plastoquinol). In the process of chemical quenching of 1O2 by the antioxidants, both short-lived products, such as oxidized carotenoids, or relative long-lived compounds, such as oxidized phenolic prenyllipids are formed. The other target of 1O2 are unsaturated fatty acids of membrane lipids that undergo peroxidation as a result of the reaction. Some of the 1O2 oxidation products, like β-cyclocitral can be components of 1O2-signallingsignaling pathway leading to acclimatory responses of plants, while some others further fulfill antioxidant functions, like hydroxy-plastochromanol or hydroxy-plastoquinol. As most of the 1O2 oxidation products are specific compounds formed only as a results of 1O2 action, they can be very useful, specific molecular markers of 1O2-dependent oxidative stress in vivo.
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Affiliation(s)
- Jerzy Kruk
- Department of Plant Physiology and Biochemistry, Faculty of Biochemistry, Biophysics and Biotechnology, Jagiellonian University, Gronostajowa 7, 30-387 Kraków, Poland.
| | - Renata Szymańska
- Faculty of Physics and Applied Computer Science, AGH University of Science and Technology, Reymonta 19, 30-059 Kraków, Poland
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Kumar A, Prasad A, Pospíšil P. Formation of α-tocopherol hydroperoxide and α-tocopheroxyl radical: relevance for photooxidative stress in Arabidopsis. Sci Rep 2020; 10:19646. [PMID: 33184329 PMCID: PMC7665033 DOI: 10.1038/s41598-020-75634-0] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2020] [Accepted: 10/08/2020] [Indexed: 12/03/2022] Open
Abstract
Tocopherols, lipid-soluble antioxidants play a crucial role in the antioxidant defense system in higher plants. The antioxidant function of α-tocopherol has been widely studied; however, experimental data on the formation of its oxidation products is missing. In this study, we attempt to provide spectroscopic evidence on the detection of oxidation products of α-tocopherol formed by its interaction with singlet oxygen and lipid peroxyl radical. Singlet oxygen was formed using photosensitizer rose bengal and thylakoid membranes isolated from Arabidopsis thaliana. Singlet oxygen reacts with polyunsaturated fatty acid forming lipid hydroperoxide which is oxidized by ferric iron to lipid peroxyl radical. The addition of singlet oxygen to double bond carbon on the chromanol head of α-tocopherol forms α-tocopherol hydroperoxide detected using fluorescent probe swallow-tailed perylene derivative. The decomposition of α-tocopherol hydroperoxide forms α-tocopherol quinone. The hydrogen abstraction from α-tocopherol by lipid peroxyl radical forms α-tocopheroxyl radical detected by electron paramagnetic resonance. Quantification of lipid and protein hydroperoxide from the wild type and tocopherol deficient (vte1) mutant Arabidopsis leaves using a colorimetric ferrous oxidation-xylenol orange assay reveals that α-tocopherol prevents formation of both lipid and protein hydroperoxides at high light. Identification of oxidation products of α-tocopherol might contribute to a better understanding of the protective role of α-tocopherol in the prevention of oxidative damage in higher plants at high light.
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Affiliation(s)
- Aditya Kumar
- Department of Biophysics, Centre of the Region Haná for Biotechnological and Agricultural Research, Faculty of Science, Palacký University, Šlechtitelů 27, 783 71, Olomouc, Czech Republic
| | - Ankush Prasad
- Department of Biophysics, Centre of the Region Haná for Biotechnological and Agricultural Research, Faculty of Science, Palacký University, Šlechtitelů 27, 783 71, Olomouc, Czech Republic
| | - Pavel Pospíšil
- Department of Biophysics, Centre of the Region Haná for Biotechnological and Agricultural Research, Faculty of Science, Palacký University, Šlechtitelů 27, 783 71, Olomouc, Czech Republic.
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7
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Assessing the performance of membrane photobioreactors (MPBR) for polishing effluents containing different types of nitrogen. ALGAL RES 2020. [DOI: 10.1016/j.algal.2020.102013] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/07/2022]
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8
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Zheng L, Jin J, Shi L, Huang J, Chang M, Wang X, Zhang H, Jin Q. Gamma tocopherol, its dimmers, and quinones: Past and future trends. Crit Rev Food Sci Nutr 2020; 60:3916-3930. [DOI: 10.1080/10408398.2020.1711704] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Affiliation(s)
- Liyou Zheng
- National Engineering Research Center for Functional Food, Collaborative Innovation Center of Food Safety and Quality Control in Jiangsu Province, School of Food Science and Technology, Jiangnan University, Jiangsu, P. R. China
| | - Jun Jin
- National Engineering Research Center for Functional Food, Collaborative Innovation Center of Food Safety and Quality Control in Jiangsu Province, School of Food Science and Technology, Jiangnan University, Jiangsu, P. R. China
| | - Longkai Shi
- National Engineering Research Center for Functional Food, Collaborative Innovation Center of Food Safety and Quality Control in Jiangsu Province, School of Food Science and Technology, Jiangnan University, Jiangsu, P. R. China
| | - Jianhua Huang
- National Engineering Research Center for Functional Food, Collaborative Innovation Center of Food Safety and Quality Control in Jiangsu Province, School of Food Science and Technology, Jiangnan University, Jiangsu, P. R. China
| | - Ming Chang
- National Engineering Research Center for Functional Food, Collaborative Innovation Center of Food Safety and Quality Control in Jiangsu Province, School of Food Science and Technology, Jiangnan University, Jiangsu, P. R. China
| | - Xingguo Wang
- National Engineering Research Center for Functional Food, Collaborative Innovation Center of Food Safety and Quality Control in Jiangsu Province, School of Food Science and Technology, Jiangnan University, Jiangsu, P. R. China
| | - Hui Zhang
- National Engineering Research Center for Functional Food, Collaborative Innovation Center of Food Safety and Quality Control in Jiangsu Province, School of Food Science and Technology, Jiangnan University, Jiangsu, P. R. China
| | - Qingzhe Jin
- National Engineering Research Center for Functional Food, Collaborative Innovation Center of Food Safety and Quality Control in Jiangsu Province, School of Food Science and Technology, Jiangnan University, Jiangsu, P. R. China
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Szymańska R, Kruk J. Novel and rare prenyllipids - Occurrence and biological activity. PLANT PHYSIOLOGY AND BIOCHEMISTRY : PPB 2018; 122:1-9. [PMID: 29169080 DOI: 10.1016/j.plaphy.2017.11.008] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/04/2017] [Revised: 11/13/2017] [Accepted: 11/13/2017] [Indexed: 06/07/2023]
Abstract
The data presented indicate that there is a variety of unique prenyllipids, often of very limited taxonomic distribution, whose origin, biosynthesis, metabolism and biological function deserves to be elucidated. These compounds include tocoenols, tocochromanol esters, tocochromanol acids, plastoquinones and ubiquinones. Additionally, based on the available data, it can be assumed that there are still unrecognized prenyllipids, like prenylquinols fatty acid esters of the hydroquinone ring, including prenylquinol phosphates, and others, whose biological function might be of great importance. Our knowledge of these compounds is not only important from the scientific point of view, but may also be of practical significance to medicine, pharmacy or cosmetics.
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Affiliation(s)
- Renata Szymańska
- Department of Medical Physics and Biophysics, Faculty of Physics and Applied Computer Science, AGH University of Science and Technology, Reymonta 19, 30-059 Krakow, Poland.
| | - Jerzy Kruk
- Department of Plant Physiology and Biochemistry, Faculty of Biochemistry, Biophysics and Biotechnology, Jagiellonian University, Gronostajowa 7, 30-387 Kraków, Poland.
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10
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Sivakumar G, Jeong K, Lay JO. Biomass and RRR-α-tocopherol production in Stichococcus bacillaris strain siva2011 in a balloon bioreactor. Microb Cell Fact 2014; 13:79. [PMID: 24893720 PMCID: PMC4055361 DOI: 10.1186/1475-2859-13-79] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2014] [Accepted: 05/30/2014] [Indexed: 12/16/2022] Open
Abstract
Background Green microalgae represent a renewable natural source of vitamin E. Its most bioactive form is the naturally occurring RRR-α-tocopherol which is biosynthesized in photosynthetic organisms as a single stereoisomer. It is noteworthy that the natural and synthetic α-tocopherols are different biomolecular entities. This article focuses on RRR-α-tocopherol production in Stichococcus bacillaris strain siva2011 biomass in a bioreactor culture with methyl jasmonate (MeJa) elicitor. Additionally, a nonlinear mathematical model was used to quantitatively scale-up and predict the biomass production in a 20 L balloon bioreactor with dual variables such as time and volume. Results Approximately 0.6 mg/g dry weight (DW) of RRR-α-tocopherol was enhanced in S. bacillaris strain siva2011 biomass with the MeJa 50 μL/L for 24 hrs elicitations when compared to the control. The R2 value from the nonlinear model was enhanced up to 95% when compared to the linear model which significantly improved the accuracy for estimating S. bacillaris strain siva2011 biomass production in a balloon bioreactor. Conclusions S. bacillaris strain siva2011 is a new green microalga which biosynthesizes significant amounts of RRR-α-tocopherol. Systematically validated dual variable empirical data should provide key insights to multivariable or fourth order modeling for algal biomass scale-up. This bioprocess engineering should provide valuable information for industrial production of RRR-α-tocopherol from green cells.
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Affiliation(s)
- Ganapathy Sivakumar
- Arkansas Biosciences Institute and College of Agriculture and Technology, Arkansas State University, PO Box 639, Jonesboro, AR 72401, USA.
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11
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Rastogi A, Yadav DK, Szymańska R, Kruk J, Sedlářová M, Pospíšil P. Singlet oxygen scavenging activity of tocopherol and plastochromanol in Arabidopsis thaliana: relevance to photooxidative stress. PLANT, CELL & ENVIRONMENT 2014; 37:392-401. [PMID: 23848570 DOI: 10.1111/pce.12161] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/15/2013] [Revised: 07/01/2013] [Accepted: 07/02/2013] [Indexed: 05/24/2023]
Abstract
In the present study, singlet oxygen (¹O₂) scavenging activity of tocopherol and plastochromanol was examined in tocopherol cyclase-deficient mutant (vte1) of Arabidopsis thaliana lacking both tocopherol and plastochromanol. It is demonstrated here that suppression of tocopherol and plastochromanol synthesis in chloroplasts isolated from vte1 Arabidopsis plants enhanced ¹O₂ formation under high light illumination as monitored by electron paramagnetic resonance spin-trapping spectroscopy. The exposure of vte1 Arabidopsis plants to high light resulted in the formation of secondary lipid peroxidation product malondialdehyde as determined by high-pressure liquid chromatography. Furthermore, it is shown here that the imaging of ultra-weak photon emission known to reflect oxidation of lipids was unambiguously higher in vte1 Arabidopsis plants. Our results indicate that tocopherol and plastochromanol act as efficient ¹O₂ scavengers and protect effectively lipids against photooxidative damage in Arabidopsis plants.
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Affiliation(s)
- Anshu Rastogi
- Department of Biophysics, Centre of the Region Haná for Biotechnological and Agricultural Research, Faculty of Science, Palacký University, Olomouc, 783 71, Czech Republic
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Nowicka B, Kruk J. Plastoquinol is more active than α-tocopherol in singlet oxygen scavenging during high light stress of Chlamydomonas reinhardtii. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2011; 1817:389-94. [PMID: 22192719 DOI: 10.1016/j.bbabio.2011.12.002] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/27/2011] [Revised: 12/03/2011] [Accepted: 12/06/2011] [Indexed: 11/20/2022]
Abstract
In the present study, we have performed comparative analysis of different prenyllipids in Chlamydomonas reinhardtii cultures during high light stress under variety of conditions (presence of inhibitors, an uncoupler, heavy water). The obtained results indicate that plastoquinol is more active than α-tocopherol in scavenging of singlet oxygen generated in photosystem II. Besides plastoquinol, also its oxidized form, plastoquinone shows antioxidant action during the stress conditions, resulting in formation of plastoquinone-C, whose level can be regarded as an indicator of singlet oxygen oxidative stress in vivo. The pronounced stimulation of α-tocopherol consumption and α-tocopherolquinone formation by an uncoupler, FCCP, together with the results of additional model system studies, led to the suggestion that α-tocopherol can be recycled in thylakoid membranes under high light conditions from 8a-hydroperoxy-α-tocopherone, the primary oxidation product of α-tocopherol by singlet oxygen.
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Affiliation(s)
- Beatrycze Nowicka
- Department of Plant Physiology and Biochemistry, Faculty of Biochemistry, Biophysics and Biotechnology, Jagiellonian University, Kraków, Poland
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Wilhelm C, Selmar D. Energy dissipation is an essential mechanism to sustain the viability of plants: The physiological limits of improved photosynthesis. JOURNAL OF PLANT PHYSIOLOGY 2011; 168:79-87. [PMID: 20800930 DOI: 10.1016/j.jplph.2010.07.012] [Citation(s) in RCA: 90] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/10/2010] [Revised: 07/13/2010] [Accepted: 07/14/2010] [Indexed: 05/29/2023]
Abstract
In bright sunlight photosynthetic activity is limited by the enzymatic machinery of carbon dioxide assimilation. This supererogation of energy can be easily visualized by the significant increases of photosynthetic activity under high CO(2) conditions or other metabolic strategies which can increase the carbon flux from CO(2) to metabolic pools. However, even under optimal CO(2) conditions plants will provide much more NADPH+H(+) and ATP that are required for the actual demand, yielding in a metabolic situation, in which no reducible NADP(+) would be available. As a consequence, excited chlorophylls can activate oxygen to its singlet state or the photosynthetic electrons can be transferred to oxygen, producing highly active oxygen species such as the superoxide anion, hydroxyl radicals and hydrogen peroxide. All of them can initiate radical chain reactions which degrade proteins, pigments, lipids and nucleotides. Therefore, the plants have developed protection and repair mechanism to prevent photodamage and to maintain the physiological integrity of metabolic apparatus. The first protection wall is regulatory energy dissipation on the level of the photosynthetic primary reactions by the so-called non-photochemical quenching. This dissipative pathway is under the control of the proton gradient generated by the electron flow and the xanthophyll cycle. A second protection mechanism is the effective re-oxidation of the reduction equivalents by so-called "alternative electron cycling" which includes the water-water cycle, the photorespiration, the malate valve and the action of antioxidants. The third system of defence is the repair of damaged components. Therefore, plants do not suffer from energy shortage, but instead they have to invest in proteins and cellular components which protect the plants from potential damage by the supererogation of energy. Under this premise, our understanding and evaluation for certain energy dissipating processes such as non-photochemical quenching or photorespiration appear in a quite new perspective, especially when discussing strategies to improve the solar energy conversion into plant biomass.
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Affiliation(s)
- Christian Wilhelm
- Institut für Biologie I, Universität Leipzig, Johannisallee 21-23, Leipzig, Germany.
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15
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Nowicka B, Kruk J. Occurrence, biosynthesis and function of isoprenoid quinones. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2010; 1797:1587-605. [PMID: 20599680 DOI: 10.1016/j.bbabio.2010.06.007] [Citation(s) in RCA: 303] [Impact Index Per Article: 21.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/13/2010] [Revised: 06/09/2010] [Accepted: 06/14/2010] [Indexed: 12/23/2022]
Abstract
Isoprenoid quinones are one of the most important groups of compounds occurring in membranes of living organisms. These compounds are composed of a hydrophilic head group and an apolar isoprenoid side chain, giving the molecules a lipid-soluble character. Isoprenoid quinones function mainly as electron and proton carriers in photosynthetic and respiratory electron transport chains and these compounds show also additional functions, such as antioxidant function. Most of naturally occurring isoprenoid quinones belong to naphthoquinones or evolutionary younger benzoquinones. Among benzoquinones, the most widespread and important are ubiquinones and plastoquinones. Menaquinones, belonging to naphthoquinones, function in respiratory and photosynthetic electron transport chains of bacteria. Phylloquinone K(1), a phytyl naphthoquinone, functions in the photosynthetic electron transport in photosystem I. Ubiquinones participate in respiratory chains of eukaryotic mitochondria and some bacteria. Plastoquinones are components of photosynthetic electron transport chains of cyanobacteria and plant chloroplasts. Biosynthetic pathway of isoprenoid quinones has been described, as well as their additional, recently recognized, diverse functions in bacterial, plant and animal metabolism.
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Affiliation(s)
- Beatrycze Nowicka
- Department of Plant Physiology and Biochemistry, Faculty of Biochemistry, Biophysics and Biotechnology, Jagiellonian University, Gronostajowa 7, 30-387 Kraków, Poland
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Tlili N, Nasri N, Saadaoui E, Khaldi A, Triki S. Carotenoid and tocopherol composition of leaves, buds, and flowers of Capparis spinosa grown wild in Tunisia. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2009; 57:5381-5385. [PMID: 19473002 DOI: 10.1021/jf900457p] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
High-performance liquid chromatography was used to determine carotenoids (beta-carotene, lutein, neoxanthin, and violaxanthin) and tocopherols of leaves, buds, and flowers of Tunisian Capparis spinosa. This plant shows strong resistance to hard environmental conditions, and it is one of the most commonly found aromatics in the Mediterranean kitchen. In this study, the means of the total carotenoids were 3452.5 +/- 1639.4, 1002 +/- 518.5, and 342.7 +/- 187.9 microg/g fresh weight (FW) in leaves, buds, and flowers, respectively. Lutein accounts for the high content. Violaxanthin provided the lowest portion of the total carotenoids. The principal form of tocopherol detected in leaves was alpha-tocopherol (20.19 +/- 10 mg/100 g FW). In buds and flowers, there were both alpha- (49.12 +/- 17.48 and 28.68 +/- 9.13 mg/100 g FW, respectively) and gamma-tocopherol (48.13 +/- 15.08 and 27.8 +/- 16.01 mg/100 g FW, respectively). The combined content of pro-vitamin A and vitamin E in capers encourages researchers to more explore and find developments for this plant.
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Affiliation(s)
- Nizar Tlili
- Département de Biologie, Faculté des Sciences de Tunis, Laboratoire de Biochimie, Université Tunis El-Manar, Tunis, Tunisia.
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Gruszka J, Pawlak A, Kruk J. Tocochromanols, plastoquinol, and other biological prenyllipids as singlet oxygen quenchers-determination of singlet oxygen quenching rate constants and oxidation products. Free Radic Biol Med 2008; 45:920-8. [PMID: 18634868 DOI: 10.1016/j.freeradbiomed.2008.06.025] [Citation(s) in RCA: 84] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/25/2008] [Revised: 06/05/2008] [Accepted: 06/23/2008] [Indexed: 11/18/2022]
Abstract
Singlet oxygen quenching rate constants for tocopherol and tocotrienol homologues have been determined in organic solvents of different polarities, as well as for other biological prenyllipids such as plastoquinol, ubiquinol, and alpha-tocopherolquinol. The obtained results showed that the quenching activity of tocochromanols was mainly due to the chromanol ring of the molecule and the activity increased with the number of the methyl groups in the ring and solvent polarity. Among prenylquinols, alpha-tocopherolquinol was the most active scavenger of singlet oxygen followed by ubiquinol and plastoquinol. The oxidation products of tocopherols were identified as 8a-hydroperoxy-tocopherones which are converted to the corresponding tocopherolquinones under acidic conditions. The primary oxidation products of prenylquinols, containing unsaturated side chains, were the corresponding prenylquinones that were further oxidized to hydroxyl side-chain derivatives. In the case of plastochromanol, the gamma-tocotrienol homologue found in some seed oils, mainly the hydroxyl derivatives were formed, although 8a-hydroperoxy-gamma-tocopherones were also formed to a minor extent, both from plastochromanol and from its hydroxyl, side-chain derivatives. The obtained results were discussed in terms of the activity of different prenyllipids as singlet oxygen scavengers in vivo.
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Affiliation(s)
- Jolanta Gruszka
- Department of Plant Physiology and Biochemistry, Faculty of Biochemistry, Biophysics and Biotechnology, Jagiellonian University, Gronostajowa 7, 30-387 Kraków, Poland
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Szymańska R, Kruk J. Gamma-tocopherol dominates in young leaves of runner bean (Phaseolus coccineus) under a variety of growing conditions: the possible functions of gamma-tocopherol. PHYTOCHEMISTRY 2008; 69:2142-2148. [PMID: 18582912 DOI: 10.1016/j.phytochem.2008.05.008] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/07/2008] [Revised: 05/10/2008] [Accepted: 05/13/2008] [Indexed: 05/26/2023]
Abstract
It has been shown that young leaves of runner bean (Phaseolus coccineus) plants grown under natural conditions have an unusually high content of gamma-tocopherol, accounting for up to 90% of all tocopherols and 50% of the chlorophyll content. The level of gamma-tocopherol gradually decreased during the first two weeks of leaf development. The high content of gamma-tocopherol in young leaves was not significantly influenced by growth conditions. In contrast to seeds, gamma-tocopherol was also the main tocopherol found in light-grown and etiolated primary leaves of runner bean. The obtained results suggest that gamma-tocopherol decline during leaf development is not only due to conversion of gamma- to alpha-tocopherol but probably also due to degradation of gamma-tocopherol to non-tocochromanol compounds. We have also shown that gamma-tocopherol found in young leaves is mainly localized in thylakoid membranes within chloroplast. In the primary leaves subjected to different abiotic stresses, only during simultaneous drought and light stress, gamma-tocopherolquinone, an oxidation product of gamma-tocopherol, was preferentially accumulated. Since one of the other possible functions of gamma-tocopherol could be its action as a nitric oxide scavenger, young leaves were analyzed for the presence of nitro-gamma-tocopherol. However, despite the use of a sensitive detection method, it was not found. The possible physiological function of the increased level of gamma-tocopherol in the young leaves was discussed.
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Affiliation(s)
- Renata Szymańska
- Department of Plant Physiology and Biochemistry, Faculty of Biochemistry, Biophysics and Biotechnology, Jagiellonian University, Gronostajowa 7, 30-387 Kraków, Poland
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