1
|
Kozuleva MA, Ivanov BN. Superoxide Anion Radical Generation in Photosynthetic Electron Transport Chain. BIOCHEMISTRY. BIOKHIMIIA 2023; 88:1045-1060. [PMID: 37758306 DOI: 10.1134/s0006297923080011] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/09/2023] [Revised: 06/16/2023] [Accepted: 06/18/2023] [Indexed: 10/03/2023]
Abstract
This review analyzes data available in the literature on the rates, characteristics, and mechanisms of oxygen reduction to a superoxide anion radical at the sites of photosynthetic electron transport chain where this reduction has been established. The existing assumptions about the role of the components of these sites in this process are critically examined using thermodynamic approaches and results of the recent studies. The process of O2 reduction at the acceptor side of PSI, which is considered the main site of this process taking place in the photosynthetic chain, is described in detail. Evolution of photosynthetic apparatus in the context of controlling the leakage of electrons to O2 is explored. The reasons limiting application of the results obtained with the isolated segments of the photosynthetic chain to estimate the rates of O2 reduction at the corresponding sites in the intact thylakoid membrane are discussed.
Collapse
Affiliation(s)
- Marina A Kozuleva
- Institute of Basic Biological Problems, Pushchino Scientific Center for Biological Research of the Russian Academy of Sciences, Pushchino, Moscow Region, 142290, Russia.
| | - Boris N Ivanov
- Institute of Basic Biological Problems, Pushchino Scientific Center for Biological Research of the Russian Academy of Sciences, Pushchino, Moscow Region, 142290, Russia
| |
Collapse
|
2
|
Cruz de Carvalho R, Feijão E, Matos AR, Cabrita MT, Utkin AB, Novais SC, Lemos MFL, Caçador I, Marques JC, Reis-Santos P, Fonseca VF, Duarte B. Ecotoxicological Effects of the Anionic Surfactant Sodium Dodecyl Sulfate (SDS) in Two Marine Primary Producers: Phaeodactylum tricornutum and Ulva lactuca. TOXICS 2022; 10:toxics10120780. [PMID: 36548613 PMCID: PMC9785791 DOI: 10.3390/toxics10120780] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/15/2022] [Revised: 12/08/2022] [Accepted: 12/11/2022] [Indexed: 05/14/2023]
Abstract
Sodium Dodecyl Sulfate (SDS) is an anionic surfactant, extensively used in detergents, household and personal care products, as well as in industrial processes. The present study aimed to disclose the potential toxicological effects of SDS exposure under environmentally relevant concentrations (0, 0.1, 1, 3, and 10 mg L-1) on the physiology and biochemistry (photosynthesis, pigment, and lipid composition, antioxidative systems, and energy balance) of two marine autotrophs: the diatom Phaeodactylum tricornutum and the macroalgae Ulva lactuca. A growth rate (GR) reduction in P. tricornutum was observed with a classic dose-response effect towards the highest applied concentration, while a GR increase occurred in U. lactuca. Regarding photochemistry, the decrease in the fluorescence of the OJIP curves and laser-induced fluorescence allowed a better separation between SDS treatments in U. lactuca compared with P. tricornutum. Although all pigments significantly decreased in U. lactuca at the highest concentrations (except for antheraxanthin), no significant variations occurred in P. tricornutum. On the other hand, changes in fatty acid content were observed in P. tricornutum but not in U. lactuca. In terms of classical biomarker assessment, a dose-effect relationship of individual biomarkers versus SDS dose applied; U. lactuca displayed a higher number of biomarker candidates, including those in distinct metabolic pathways, increasing its usefulness for ecotoxicological applications. By evaluating the potential application of optical and biochemical traits, it was evident that the fatty acid profiles of the different exposure groups are excellent candidates in P. tricornutum, concomitant with the characteristics of this anionic surfactant. On the other hand, the results presented by laser-induced fluorescence and some parameters of PAM fluorometry in U. lactuca may be an advantage in the field, offering non-invasive, fast, easy-to-use, high-throughput screening techniques as excellent tools for ecotoxicology assessment.
Collapse
Affiliation(s)
- Ricardo Cruz de Carvalho
- MARE–Marine and Environmental Sciences Centre, ARNET–Aquatic Research Network Associate Laboratory, Faculdade de Ciências da Universidade de Lisboa, Campo Grande, 1749-016 Lisbon, Portugal
- cE3c–Centre for Ecology, Evolution and Environmental Changes, Faculty of Sciences, University of Lisbon, Campo Grande, Edifício C2, Piso 5, 1749-016 Lisbon, Portugal
- Departamento de Biologia Vegetal, Faculdade de Ciências da Universidade de Lisboa, Campo Grande, 1749-016 Lisboa, Portugal
- Correspondence:
| | - Eduardo Feijão
- MARE–Marine and Environmental Sciences Centre, ARNET–Aquatic Research Network Associate Laboratory, Faculdade de Ciências da Universidade de Lisboa, Campo Grande, 1749-016 Lisbon, Portugal
| | - Ana Rita Matos
- Departamento de Biologia Vegetal, Faculdade de Ciências da Universidade de Lisboa, Campo Grande, 1749-016 Lisboa, Portugal
- BioISI–Instituto de Biosistemas e Ciências Integrativas, Faculdade de Ciências, Universidade de Lisboa, 1749-016 Lisboa, Portugal
| | - Maria Teresa Cabrita
- Centro de Estudos Geográficos (CEG), Instituto de Geografia e Ordenamento do Território (IGOT), Universidade de Lisboa, Rua Branca Edmée Marques, 1600-276 Lisboa, Portugal
- Laboratório Associado TERRA, Edifício Prof. Azevedo Gomes, Instituto Superior de Agronomia, Tapada da Ajuda, 1349-017 Lisboa, Portugal
| | - Andrei B. Utkin
- INOV-INESC, Rua Alves Redol 9, 1000-029 Lisboa, Portugal
- CeFEMA, Universidade de Lisboa, Av. Rovisco Pais 1, 1049-001 Lisboa, Portugal
| | - Sara C. Novais
- MARE–Marine and Environmental Sciences Centre, ARNET–Aquatic Research Network Associate Laboratory, ESTM, Polytechnic of Leiria, 2520-641 Peniche, Portugal
| | - Marco F. L. Lemos
- MARE–Marine and Environmental Sciences Centre, ARNET–Aquatic Research Network Associate Laboratory, ESTM, Polytechnic of Leiria, 2520-641 Peniche, Portugal
| | - Isabel Caçador
- MARE–Marine and Environmental Sciences Centre, ARNET–Aquatic Research Network Associate Laboratory, Faculdade de Ciências da Universidade de Lisboa, Campo Grande, 1749-016 Lisbon, Portugal
- Departamento de Biologia Vegetal, Faculdade de Ciências da Universidade de Lisboa, Campo Grande, 1749-016 Lisboa, Portugal
| | - João Carlos Marques
- MARE–Marine and Environmental Sciences Centre, ARNET–Aquatic Research Network, Department of Life Sciences, University of Coimbra, 3000 Coimbra, Portugal
| | - Patrick Reis-Santos
- MARE–Marine and Environmental Sciences Centre, ARNET–Aquatic Research Network Associate Laboratory, Faculdade de Ciências da Universidade de Lisboa, Campo Grande, 1749-016 Lisbon, Portugal
- Southern Seas Ecology Laboratories, School of Biological Sciences, The University of Adelaide, Adelaide, SA 5005, Australia
| | - Vanessa F. Fonseca
- MARE–Marine and Environmental Sciences Centre, ARNET–Aquatic Research Network Associate Laboratory, Faculdade de Ciências da Universidade de Lisboa, Campo Grande, 1749-016 Lisbon, Portugal
- Departamento de Biologia Animal, Faculdade de Ciências, Universidade de Lisboa, Campo Grande, 1749-016 Lisboa, Portugal
| | - Bernardo Duarte
- MARE–Marine and Environmental Sciences Centre, ARNET–Aquatic Research Network Associate Laboratory, Faculdade de Ciências da Universidade de Lisboa, Campo Grande, 1749-016 Lisbon, Portugal
- Departamento de Biologia Vegetal, Faculdade de Ciências da Universidade de Lisboa, Campo Grande, 1749-016 Lisboa, Portugal
| |
Collapse
|
3
|
Bicarbonate-controlled reduction of oxygen by the Q A semiquinone in Photosystem II in membranes. Proc Natl Acad Sci U S A 2022; 119:2116063119. [PMID: 35115403 PMCID: PMC8833163 DOI: 10.1073/pnas.2116063119] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/23/2021] [Indexed: 12/15/2022] Open
Abstract
In Photosystem II (PSII), O2 reduction by QA•− is often discussed but has not been demonstrated. Here, we show in PSII membranes that QA•− can reduce O2 to superoxide, but only when bicarbonate is absent from its binding site on the nonheme Fe2+. Bicarbonate’s role in PSII was recently shown to involve a regulatory/protective redox-tuning mechanism linking PSII function to CO2 concentration. A key aspect is the presence of stable QA•− causing release of bicarbonate from its site on Fe2+. Here, we show that under these conditions, O2 binds to the empty site on the Fe2+ and is reduced by QA•−. This unexpected reaction may be a further indication of cross-talk between the regulation of PSII and CO2 fixation. Photosystem II (PSII), the water/plastoquinone photo-oxidoreductase, plays a key energy input role in the biosphere. QA•−, the reduced semiquinone form of the nonexchangeable quinone, is often considered capable of a side reaction with O2, forming superoxide, but this reaction has not yet been demonstrated experimentally. Here, using chlorophyll fluorescence in plant PSII membranes, we show that O2 does oxidize QA•− at physiological O2 concentrations with a t1/2 of 10 s. Superoxide is formed stoichiometrically, and the reaction kinetics are controlled by the accessibility of O2 to a binding site near QA•−, with an apparent dissociation constant of 70 ± 20 µM. Unexpectedly, QA•− could only reduce O2 when bicarbonate was absent from its binding site on the nonheme iron (Fe2+) and the addition of bicarbonate or formate blocked the O2-dependant decay of QA•−. These results, together with molecular dynamics simulations and hybrid quantum mechanics/molecular mechanics calculations, indicate that electron transfer from QA•− to O2 occurs when the O2 is bound to the empty bicarbonate site on Fe2+. A protective role for bicarbonate in PSII was recently reported, involving long-lived QA•− triggering bicarbonate dissociation from Fe2+ [Brinkert et al., Proc. Natl. Acad. Sci. U.S.A. 113, 12144–12149 (2016)]. The present findings extend this mechanism by showing that bicarbonate release allows O2 to bind to Fe2+ and to oxidize QA•−. This could be beneficial by oxidizing QA•− and by producing superoxide, a chemical signal for the overreduced state of the electron transfer chain.
Collapse
|
4
|
Mahapatra K, Banerjee S, De S, Mitra M, Roy P, Roy S. An Insight Into the Mechanism of Plant Organelle Genome Maintenance and Implications of Organelle Genome in Crop Improvement: An Update. Front Cell Dev Biol 2021; 9:671698. [PMID: 34447743 PMCID: PMC8383295 DOI: 10.3389/fcell.2021.671698] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2021] [Accepted: 07/21/2021] [Indexed: 12/19/2022] Open
Abstract
Besides the nuclear genome, plants possess two small extra chromosomal genomes in mitochondria and chloroplast, respectively, which contribute a small fraction of the organelles’ proteome. Both mitochondrial and chloroplast DNA have originated endosymbiotically and most of their prokaryotic genes were either lost or transferred to the nuclear genome through endosymbiotic gene transfer during the course of evolution. Due to their immobile nature, plant nuclear and organellar genomes face continuous threat from diverse exogenous agents as well as some reactive by-products or intermediates released from various endogenous metabolic pathways. These factors eventually affect the overall plant growth and development and finally productivity. The detailed mechanism of DNA damage response and repair following accumulation of various forms of DNA lesions, including single and double-strand breaks (SSBs and DSBs) have been well documented for the nuclear genome and now it has been extended to the organelles also. Recently, it has been shown that both mitochondria and chloroplast possess a counterpart of most of the nuclear DNA damage repair pathways and share remarkable similarities with different damage repair proteins present in the nucleus. Among various repair pathways, homologous recombination (HR) is crucial for the repair as well as the evolution of organellar genomes. Along with the repair pathways, various other factors, such as the MSH1 and WHIRLY family proteins, WHY1, WHY2, and WHY3 are also known to be involved in maintaining low mutation rates and structural integrity of mitochondrial and chloroplast genome. SOG1, the central regulator in DNA damage response in plants, has also been found to mediate endoreduplication and cell-cycle progression through chloroplast to nucleus retrograde signaling in response to chloroplast genome instability. Various proteins associated with the maintenance of genome stability are targeted to both nuclear and organellar compartments, establishing communication between organelles as well as organelles and nucleus. Therefore, understanding the mechanism of DNA damage repair and inter compartmental crosstalk mechanism in various sub-cellular organelles following induction of DNA damage and identification of key components of such signaling cascades may eventually be translated into strategies for crop improvement under abiotic and genotoxic stress conditions. This review mainly highlights the current understanding as well as the importance of different aspects of organelle genome maintenance mechanisms in higher plants.
Collapse
Affiliation(s)
- Kalyan Mahapatra
- Department of Botany, UGC Center for Advanced Studies, The University of Burdwan, Burdwan, India
| | - Samrat Banerjee
- Department of Botany, UGC Center for Advanced Studies, The University of Burdwan, Burdwan, India
| | - Sayanti De
- Department of Botany, UGC Center for Advanced Studies, The University of Burdwan, Burdwan, India
| | - Mehali Mitra
- Department of Botany, UGC Center for Advanced Studies, The University of Burdwan, Burdwan, India
| | - Pinaki Roy
- Department of Botany, UGC Center for Advanced Studies, The University of Burdwan, Burdwan, India
| | - Sujit Roy
- Department of Botany, UGC Center for Advanced Studies, The University of Burdwan, Burdwan, India
| |
Collapse
|
5
|
Alber NA, Vanlerberghe GC. The flexibility of metabolic interactions between chloroplasts and mitochondria in Nicotiana tabacum leaf. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2021; 106:1625-1646. [PMID: 33811402 DOI: 10.1111/tpj.15259] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/26/2021] [Revised: 03/24/2021] [Accepted: 03/26/2021] [Indexed: 05/02/2023]
Abstract
To examine the effect of mitochondrial function on photosynthesis, wild-type and transgenic Nicotiana tabacum with varying amounts of alternative oxidase (AOX) were treated with different respiratory inhibitors. Initially, each inhibitor increased the reduction state of the chloroplast electron transport chain, most severely in AOX knockdowns and least severely in AOX overexpressors. This indicated that the mitochondrion was a necessary sink for photo-generated reductant, contributing to the 'P700 oxidation capacity' of photosystem I. Initially, the Complex III inhibitor myxothiazol and the mitochondrial ATP synthase inhibitor oligomycin caused an increase in photosystem II regulated non-photochemical quenching not evident with the Complex III inhibitor antimycin A (AA). This indicated that the increased quenching depended upon AA-sensitive cyclic electron transport (CET). Following 12 h with oligomycin, the reduction state of the chloroplast electron transport chain recovered in all plant lines. Recovery was associated with large increases in the protein amount of chloroplast ATP synthase and mitochondrial uncoupling protein. This increased the capacity for photophosphorylation in the absence of oxidative phosphorylation and enabled the mitochondrion to act again as a sink for photo-generated reductant. Comparing the AA and myxothiazol treatments at 12 h showed that CET optimized photosystem I quantum yield, depending upon the P700 oxidation capacity. When this capacity was too high, CET drew electrons away from other sinks, moderating the P700+ amount. When P700 oxidation capacity was too low, CET acted as an electron overflow, moderating the amount of reduced P700. This study reveals flexible chloroplast-mitochondrion interactions able to overcome lesions in energy metabolism.
Collapse
Affiliation(s)
- Nicole A Alber
- Department of Biological Sciences, Department of Cell and Systems Biology, University of Toronto Scarborough, 1265 Military Trail, Toronto, ON, M1C1A4, Canada
| | - Greg C Vanlerberghe
- Department of Biological Sciences, Department of Cell and Systems Biology, University of Toronto Scarborough, 1265 Military Trail, Toronto, ON, M1C1A4, Canada
| |
Collapse
|
6
|
Li T, Chen X, Lin S. Physiological and transcriptomic responses to N-deficiency and ammonium: Nitrate shift in Fugacium kawagutii (Symbiodiniaceae). THE SCIENCE OF THE TOTAL ENVIRONMENT 2021; 753:141906. [PMID: 32890873 DOI: 10.1016/j.scitotenv.2020.141906] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/12/2020] [Revised: 08/20/2020] [Accepted: 08/21/2020] [Indexed: 06/11/2023]
Abstract
Symbiodiniaceae are the source of essential coral symbionts of reef building corals. The growth and density of endosymbiotic Symbiodiniaceae within the coral host is dependent on nutrient availability, yet little is known about how Symbiodiniaceae respond to the dynamics of the nutrients, including switch between different chemical forms and changes in abundance. In this study, we investigated physiological, cytometric, and transcriptomic responses in Fugacium kawagutii to nitrogen (N)-nutrient deficiency and different chemical N forms (nitrate and ammonium) in batch culture conditions. We mainly found that ammonium was consumed faster than nitrate when provided separately, and was preferentially utilized over nitrate when both N compounds were supplied at 1:2, 1:1 and 2:1 molarity ratios. Besides, N-deficiency caused decreases in growth, energy production, antioxidative capacity and investment in photosynthate transport but increased energy consumption. Growing on ammonium produced a similar cell yield as nitrate, but with a reduced investment in nutrient transport and assimilation; yet at high concentrations ammonium exhibited inhibitory effects. These findings together have important implications in N-nutrient regulation of coral symbiosis. In addition, we identified ten highly and stably expressed genes as candidate reference genes, which will be potentially useful for gene expression studies in the future.
Collapse
Affiliation(s)
- Tangcheng Li
- State Key Laboratory of Marine Environmental Science and College of Ocean and Earth Sciences, Xiamen University, Xiamen 361102, China; Department of Marine Sciences, University of Connecticut, Groton, CT 06340, USA
| | - Xibei Chen
- State Key Laboratory of Marine Environmental Science and College of Ocean and Earth Sciences, Xiamen University, Xiamen 361102, China
| | - Senjie Lin
- State Key Laboratory of Marine Environmental Science and College of Ocean and Earth Sciences, Xiamen University, Xiamen 361102, China; Laboratory of Marine Biology and Biotechnology, Qingdao National Laboratory of Marine Science and Technology, Qingdao 266237, China; Department of Marine Sciences, University of Connecticut, Groton, CT 06340, USA.
| |
Collapse
|
7
|
Essemine J, Qu M, Lyu MJA, Song Q, Khan N, Chen G, Wang P, Zhu XG. Photosynthetic and transcriptomic responses of two C 4 grass species with different NaCl tolerance. JOURNAL OF PLANT PHYSIOLOGY 2020; 253:153244. [PMID: 32818766 DOI: 10.1016/j.jplph.2020.153244] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/30/2020] [Revised: 07/16/2020] [Accepted: 07/16/2020] [Indexed: 05/15/2023]
Abstract
This report reveals the effects of salt on the photosynthetic electron transport and transcriptome of the glycophyte Setaria viridis (S. viridis) and its salt-tolerant close relative halophyte Spartina alterniflora (S. alterniflora). S. viridis was unable to survive exposed to sodium chloride (NaCl) levels higher than 100 mM, in contrast, S. alterniflora could tolerate NaCl up to 550 mM, with negligible effect on gas exchange related parameters and conductance of electrons transport chain (gETC). Under salt, the prompt fluorescence (OJIP-curves) exhibits an increase in the O- and J-steps in S. viridis and much less for S. alterniflora. Flowing NaCl stress, a dramatic decline in the photosystem II (PSII) primary photochemistry was observed for S. viridis, as reflected by the drastic drop in Fv/Fm, Fv/Fo and ΦPSII; however, no substantial change was recorded for these parameters in S. alterniflora. Interestingly, we found an increase in the primary PSII photochemistry (ΦPSII) for S. alterniflora with increasing either NaCl concentration or NaCl treatment duration. The NPQ magnitude was strongly enhanced for S. viridis even at a low NaCl (50 mM); however, it remains unchangeable or slightly increased for S. alterniflora at NaCl levels above 400 mM. After NaCl treatment, we found an increase in both the proportion of oxidized P700 and the amount of active P700 in S. viridis and almost no change for S. alterniflora. Under salt, the net photosynthetic rate (A) and stomatal conductance (gs) measurements demonstrate that A decreases earlier in S. viridis, even after one week exposure to only 50 mM NaCl; in contrast, in S. alterniflora, the effect of NaCl on A and gs was minor even after exposure for two weeks to high NaCl levels. For S. viridis exposed to 50 mM NaCl for 12 d, carbon dioxide (CO2) at a concentration of 2000 μL L-1 could not fully restore A to the control (Ctrl) level. Conversely, in S. alterniflora, high CO2 can fully restore A for all NaCl treatments except at 550 mM. RNA-seq data shows a major impact of NaCl on metabolic pathways in S. viridis and we found a number of transcription factors potentially related to NaCl responses. For S. alterniflora, no major changes in the transcriptomic levels were recorded under NaCl stress. To confirm our data analysis of RNA-seq, we performed quantitative reverse transcription polymerase chain reaction (qRT-PCR) analysis for randomly selected four genes for each species (8 genes in total) and we found that our results (up- and/or down-regulated genes) are fully consistent and match well our RNA-seq data. Overall, this study showed drastically different photosynthetic and transcriptomic responses of a salt-tolerant C4 grass species and one salt-sensitive C4 grass species to NaCl stress, which suggests that S. alterniflora could be used as a promising model species to study salt tolerance in C4 or monocot species.
Collapse
Affiliation(s)
- Jemaa Essemine
- National Key Laboratory of Plant Molecular Genetics, CAS-Center for Excellence in Molecular Plant Sciences, Institute of Plant Physiology and Ecology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, 200032, Shanghai, China
| | - Mingnan Qu
- National Key Laboratory of Plant Molecular Genetics, CAS-Center for Excellence in Molecular Plant Sciences, Institute of Plant Physiology and Ecology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, 200032, Shanghai, China
| | - Ming-Ju Amy Lyu
- National Key Laboratory of Plant Molecular Genetics, CAS-Center for Excellence in Molecular Plant Sciences, Institute of Plant Physiology and Ecology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, 200032, Shanghai, China
| | - Qingfeng Song
- National Key Laboratory of Plant Molecular Genetics, CAS-Center for Excellence in Molecular Plant Sciences, Institute of Plant Physiology and Ecology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, 200032, Shanghai, China
| | - Naveed Khan
- National Key Laboratory of Plant Molecular Genetics, CAS-Center for Excellence in Molecular Plant Sciences, Institute of Plant Physiology and Ecology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, 200032, Shanghai, China
| | - Genyun Chen
- National Key Laboratory of Plant Molecular Genetics, CAS-Center for Excellence in Molecular Plant Sciences, Institute of Plant Physiology and Ecology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, 200032, Shanghai, China
| | - Peng Wang
- CAS-Center for Excellence in Molecular Plant Sciences, Institute of Plant Physiology and Ecology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, 200032, Shanghai, China
| | - Xin-Guang Zhu
- National Key Laboratory of Plant Molecular Genetics, CAS-Center for Excellence in Molecular Plant Sciences, Institute of Plant Physiology and Ecology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, 200032, Shanghai, China.
| |
Collapse
|
8
|
Feijão E, Cruz de Carvalho R, Duarte IA, Matos AR, Cabrita MT, Novais SC, Lemos MFL, Caçador I, Marques JC, Reis-Santos P, Fonseca VF, Duarte B. Fluoxetine Arrests Growth of the Model Diatom Phaeodactylum tricornutum by Increasing Oxidative Stress and Altering Energetic and Lipid Metabolism. Front Microbiol 2020; 11:1803. [PMID: 32849412 PMCID: PMC7411086 DOI: 10.3389/fmicb.2020.01803] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2020] [Accepted: 07/09/2020] [Indexed: 11/13/2022] Open
Abstract
Pharmaceutical residues impose a new and emerging threat to aquatic environments and its biota. One of the most commonly prescribed pharmaceuticals is the antidepressant fluoxetine, a selective serotonin re-uptake inhibitor that has been frequently detected, in concentrations up to 40 μg L–1, in aquatic ecosystems. The present study aims to investigate the ecotoxicity of fluoxetine at environmentally relevant concentrations (0.3, 0.6, 20, 40, and 80 μg L–1) on cell energy and lipid metabolism, as well as oxidative stress biomarkers in the model diatom Phaeodactylum tricornutum. Exposure to higher concentrations of fluoxetine negatively affected cell density and photosynthesis through a decrease in the active PSII reaction centers. Stress response mechanisms, like β-carotene (β-car) production and antioxidant enzymes [superoxide dismutase (SOD) and ascorbate peroxidase (APX)] up-regulation were triggered, likely as a positive feedback mechanism toward formation of fluoxetine-induced reactive oxygen species. Lipid peroxidation products increased greatly at the highest fluoxetine concentration whereas no variation in the relative amounts of long chain polyunsaturated fatty acids (LC-PUFAs) was observed. However, monogalactosyldiacylglycerol-characteristic fatty acids such as C16:2 and C16:3 increased, suggesting an interaction between light harvesting pigments, lipid environment, and photosynthesis stabilization. Using a canonical multivariate analysis, it was possible to evaluate the efficiency of the application of bio-optical and biochemical techniques as potential fluoxetine exposure biomarkers in P. tricornutum. An overall classification efficiency to the different levels of fluoxetine exposure of 61.1 and 88.9% were obtained for bio-optical and fatty acids profiles, respectively, with different resolution degrees highlighting these parameters as potential efficient biomarkers. Additionally, the negative impact of this pharmaceutical molecule on the primary productivity is also evident alongside with an increase in respiratory oxygen consumption. From the ecological point of view, reduction in diatom biomass due to continued exposure to fluoxetine may severely impact estuarine and coastal trophic webs, by both a reduction in oxygen primary productivity and reduced availability of key fatty acids to the dependent heterotrophic upper levels.
Collapse
Affiliation(s)
- Eduardo Feijão
- MARE - Marine and Environmental Sciences Centre, Faculdade de Ciências da Universidade de Lisboa, Lisbon, Portugal
| | - Ricardo Cruz de Carvalho
- MARE - Marine and Environmental Sciences Centre, Faculdade de Ciências da Universidade de Lisboa, Lisbon, Portugal.,cE3c - Centre for Ecology, Evolution and Environmental Changes, Faculdade de Ciências, Universidade de Lisboa, Lisbon, Portugal
| | - Irina A Duarte
- MARE - Marine and Environmental Sciences Centre, Faculdade de Ciências da Universidade de Lisboa, Lisbon, Portugal
| | - Ana Rita Matos
- BioISI - Biosystems and Integrative Sciences Institute, Plant Functional Genomics Group, Departamento de Biologia Vegetal, Faculdade de Ciências da Universidade de Lisboa, Lisbon, Portugal
| | - Maria Teresa Cabrita
- Centro de Estudos Geográficos, Instituto de Geografia e Ordenamento do Território, University of Lisbon, Lisbon, Portugal
| | - Sara C Novais
- MARE - Marine and Environmental Sciences Centre, ESTM, Politécnico de Leiria, Peniche, Portugal
| | - Marco F L Lemos
- MARE - Marine and Environmental Sciences Centre, ESTM, Politécnico de Leiria, Peniche, Portugal
| | - Isabel Caçador
- MARE - Marine and Environmental Sciences Centre, Faculdade de Ciências da Universidade de Lisboa, Lisbon, Portugal
| | - João Carlos Marques
- MARE - Marine and Environmental Sciences Centre, Department of Zoology, Faculty of Sciences and Technology, University of Coimbra, Coimbra, Portugal
| | - Patrick Reis-Santos
- MARE - Marine and Environmental Sciences Centre, Faculdade de Ciências da Universidade de Lisboa, Lisbon, Portugal.,Southern Seas Ecology Laboratories, School of Biological Sciences, The University of Adelaide, Adelaide, SA, Australia
| | - Vanessa F Fonseca
- MARE - Marine and Environmental Sciences Centre, Faculdade de Ciências da Universidade de Lisboa, Lisbon, Portugal.,Departamento de Biologia Animal, Faculdade de Ciências da Universidade de Lisboa, Lisbon, Portugal
| | - Bernardo Duarte
- MARE - Marine and Environmental Sciences Centre, Faculdade de Ciências da Universidade de Lisboa, Lisbon, Portugal
| |
Collapse
|
9
|
Khorobrykh S, Havurinne V, Mattila H, Tyystjärvi E. Oxygen and ROS in Photosynthesis. PLANTS (BASEL, SWITZERLAND) 2020; 9:E91. [PMID: 31936893 PMCID: PMC7020446 DOI: 10.3390/plants9010091] [Citation(s) in RCA: 120] [Impact Index Per Article: 30.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/27/2019] [Revised: 12/29/2019] [Accepted: 01/02/2020] [Indexed: 12/14/2022]
Abstract
Oxygen is a natural acceptor of electrons in the respiratory pathway of aerobic organisms and in many other biochemical reactions. Aerobic metabolism is always associated with the formation of reactive oxygen species (ROS). ROS may damage biomolecules but are also involved in regulatory functions of photosynthetic organisms. This review presents the main properties of ROS, the formation of ROS in the photosynthetic electron transport chain and in the stroma of chloroplasts, and ROS scavenging systems of thylakoid membrane and stroma. Effects of ROS on the photosynthetic apparatus and their roles in redox signaling are discussed.
Collapse
Affiliation(s)
| | | | | | - Esa Tyystjärvi
- Department of Biochemistry/Molecular Plant Biology, University of Turku, FI-20014 Turku, Finland or (S.K.); (V.H.); (H.M.)
| |
Collapse
|
10
|
Zhang MM, Fan DY, Murakami K, Badger MR, Sun GY, Chow WS. Partially Dissecting Electron Fluxes in Both Photosystems in Spinach Leaf Disks during Photosynthetic Induction. PLANT & CELL PHYSIOLOGY 2019; 60:2206-2219. [PMID: 31271439 DOI: 10.1093/pcp/pcz114] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/02/2018] [Accepted: 05/29/2019] [Indexed: 06/09/2023]
Abstract
Photosynthetic induction, a gradual increase in photosynthetic rate on a transition from darkness or low light to high light, has ecological significance, impact on biomass accumulation in fluctuating light and relevance to photoprotection in strong light. However, the experimental quantification of the component electron fluxes in and around both photosystems during induction has been rare. Combining optimized chlorophyll fluorescence, the redox kinetics of P700 [primary electron donor in Photosystem I (PSI)] and membrane inlet mass spectrometry in the absence/presence of inhibitors/mediator, we partially estimated the components of electron fluxes in spinach leaf disks on transition from darkness to 1,000 �mol photons�m-2�s-1 for up to 10 min, obtaining the following findings: (i) the partitioning of energy between both photosystems did not change noticeably; (ii) in Photosystem II (PSII), the combined cyclic electron flow (CEF2) and charge recombination (CR2) to the ground state decreased gradually toward 0 in steady state; (iii) oxygen reduction by electrons from PSII, partly bypassing PSI, was small but measurable; (iv) cyclic electron flow around PSI (CEF1) peaked before becoming somewhat steady; (v) peak magnitudes of some of the electron fluxes, all probably photoprotective, were in the descending order: CEF1 > CEF2 + CR2 > chloroplast O2 uptake; and (vi) the chloroplast NADH dehydrogenase-like complex appeared to aid the antimycin A-sensitive CEF1. The results are important for fine-tuning in silico simulation of in vivo photosynthetic electron transport processes; such simulation is, in turn, necessary to probe partial processes in a complex network of interactions in response to environmental changes.
Collapse
Affiliation(s)
- Meng-Meng Zhang
- Department of Plant Physiology, College of Life Science, Northeast Forestry University, Harbin, Heilongjiang, China
- Division of Plant Sciences, Research School of Biology, The Australian National University, Acton, ACT, Australia
| | - Da-Yong Fan
- Division of Plant Sciences, Research School of Biology, The Australian National University, Acton, ACT, Australia
- College of Forestry, Beijing Forestry University, Beijing, China
| | - Keach Murakami
- Division of Plant Sciences, Research School of Biology, The Australian National University, Acton, ACT, Australia
- National Agriculture and Food Research Organization (NARO), Hokkaido Agricultural Research Center (HARC), Hitsujigaoka 1, Toyohira, Sapporo, Japan
| | - Murray R Badger
- ARC Centre of Excellence for Translational Photosynthesis, Research School of Biology, The Australian National University, Acton, ACT, Australia
| | - Guang-Yu Sun
- Department of Plant Physiology, College of Life Science, Northeast Forestry University, Harbin, Heilongjiang, China
| | - Wah Soon Chow
- ARC Centre of Excellence for Translational Photosynthesis, Research School of Biology, The Australian National University, Acton, ACT, Australia
| |
Collapse
|
11
|
Jiang SY, Ma A, Ramachandran S. Negative Air Ions and Their Effects on Human Health and Air Quality Improvement. Int J Mol Sci 2018; 19:E2966. [PMID: 30274196 PMCID: PMC6213340 DOI: 10.3390/ijms19102966] [Citation(s) in RCA: 70] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2018] [Revised: 09/13/2018] [Accepted: 09/25/2018] [Indexed: 11/16/2022] Open
Abstract
Negative air ions (NAIs) have been discovered for more than 100 years and are widely used for air cleaning. Here, we have carried out a comprehensive reviewing on the effects of NAIs on humans/animals, and microorganisms, and plant development. The presence of NAIs is credited for increasing psychological health, productivity, and overall well-being but without consistent or reliable evidence in therapeutic effects and with controversy in anti-microorganisms. Reports also showed that NAIs could help people in relieving symptoms of allergies to dust, mold spores, and other allergens. Particulate matter (PM) is a major air pollutant that affects human health. Experimental data showed that NAIs could be used to high-efficiently remove PM. Finally, we have reviewed the plant-based NAI release system under the pulsed electric field (PEF) stimulation. This is a new NAI generation system which releases a huge amount of NAIs under the PEF treatment. The system may be used to freshen indoor air and reduce PM concentration in addition to enriching oxygen content and indoor decoration at home, school, hospital, airport, and other indoor areas.
Collapse
Affiliation(s)
- Shu-Ye Jiang
- Temasek Life Sciences Laboratory, 1 Research Link, National University of Singapore, Singapore 117604, Singapore.
| | - Ali Ma
- Temasek Life Sciences Laboratory, 1 Research Link, National University of Singapore, Singapore 117604, Singapore.
| | - Srinivasan Ramachandran
- Temasek Life Sciences Laboratory, 1 Research Link, National University of Singapore, Singapore 117604, Singapore.
| |
Collapse
|
12
|
Kornienko N, Zhang JZ, Sokol KP, Lamaison S, Fantuzzi A, van Grondelle R, Rutherford AW, Reisner E. Oxygenic Photoreactivity in Photosystem II Studied by Rotating Ring Disk Electrochemistry. J Am Chem Soc 2018; 140:17923-17931. [PMID: 30188698 PMCID: PMC6311681 DOI: 10.1021/jacs.8b08784] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Protein film photoelectrochemistry has previously been used to monitor the activity of photosystem II, the water-plastoquinone photooxidoreductase, but the mechanistic information attainable from a three-electrode setup has remained limited. Here we introduce the four-electrode rotating ring disk electrode technique for quantifying light-driven reaction kinetics and mechanistic pathways in real time at the enzyme-electrode interface. This setup allows us to study photochemical H2O oxidation in photosystem II and to gain an in-depth understanding of pathways that generate reactive oxygen species. The results show that photosystem II reacts with O2 through two main pathways that both involve a superoxide intermediate to produce H2O2. The first pathway involves the established chlorophyll triplet-mediated formation of singlet oxygen, which is followed by its reduction to superoxide at the electrode surface. The second pathway is specific for the enzyme/electrode interface: an exposed antenna chlorophyll is sufficiently close to the electrode for rapid injection of an electron to form a highly reducing chlorophyll anion, which reacts with O2 in solution to produce O2•-. Incomplete H2O oxidation does not significantly contribute to reactive oxygen formation in our conditions. The rotating ring disk electrode technique allows the chemical reactivity of photosystem II to be studied electrochemically and opens several avenues for future investigation.
Collapse
Affiliation(s)
- Nikolay Kornienko
- Department of Chemistry , University of Cambridge , Lensfield Road , Cambridge CB2 1EW , U.K
| | - Jenny Z Zhang
- Department of Chemistry , University of Cambridge , Lensfield Road , Cambridge CB2 1EW , U.K
| | - Katarzyna P Sokol
- Department of Chemistry , University of Cambridge , Lensfield Road , Cambridge CB2 1EW , U.K
| | - Sarah Lamaison
- Department of Chemistry , University of Cambridge , Lensfield Road , Cambridge CB2 1EW , U.K
| | - Andrea Fantuzzi
- Department of Life Sciences , Imperial College London, South Kensington Campus , London SW7 2AZ , U.K
| | - Rienk van Grondelle
- Department of Physics and Astronomy , VU Amsterdam , De Boelelaan 1105 , 1081 HV , Amsterdam , The Netherlands
| | - A William Rutherford
- Department of Life Sciences , Imperial College London, South Kensington Campus , London SW7 2AZ , U.K
| | - Erwin Reisner
- Department of Chemistry , University of Cambridge , Lensfield Road , Cambridge CB2 1EW , U.K
| |
Collapse
|
13
|
Yanykin DV, Khorobrykh AA, Terentyev VV, Klimov VV. Two pathways of photoproduction of organic hydroperoxides on the donor side of photosystem 2 in subchloroplast membrane fragments. PHOTOSYNTHESIS RESEARCH 2017; 133:129-138. [PMID: 28349346 DOI: 10.1007/s11120-017-0373-z] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/17/2016] [Accepted: 03/20/2017] [Indexed: 06/06/2023]
Abstract
Earlier the catalase-insensitive formation of organic hydroperoxides (via the interaction of organic radicals produced due to redox activity of P680+· (or TyrZ·) with molecular oxygen) has been found in Mn-depleted PS2 preparations (apo-WOC-PS2) by Khorobrykh et al. (Biochemistry 50:10658-10665, 2011). The present work describes a second pathway of the photoproduction of organic peroxides on the donor side of PS2. It was shown that illumination of CaCl2-treated PS2 membranes (deprived of the PS2 extrinsic proteins without removal of the Mn-containing water-oxidizing complex) (CaCl2-PS2) led to the photoproduction of highly lipophilic organic hydroperoxides (LP-OOH) (in amount corresponding to 1.5 LP-OOH per one reaction center of PS2) which significantly increased upon the addition of exogenous electron acceptor potassium ferricyanide (to 4.2 LP-OOH per one reaction center). Addition of catalase (200 U/ml) before illumination inhibited ferricyanide-induced photoproduction of hydroperoxides while no effect was obtained by adding catalase after illumination or by adding inactivated catalase before illumination. The hydroperoxide photoproduction was inhibited by the addition of exogenous electron donor for PS2, diphenylcarbazide or diuron (inhibitor of the electron transfer in PS2). The addition of exogenous hydrogen peroxide to the CaCl2-PS2 led to the production of highly lipophilic organic hydroperoxides in the dark (3.2 LP-OOH per one reaction center). We suggest that the photoproduction of highly lipophilic organic hydroperoxides in CaCl2-PS2 preparations occurs via redox activity of H2O2 produced on the donor side of PS2.
Collapse
Affiliation(s)
- D V Yanykin
- Institute of Basic Biological Problems, Russian Academy of Sciences, Pushchino, Moscow Region, Russia, 142290.
| | - A A Khorobrykh
- Institute of Basic Biological Problems, Russian Academy of Sciences, Pushchino, Moscow Region, Russia, 142290
| | - V V Terentyev
- Institute of Basic Biological Problems, Russian Academy of Sciences, Pushchino, Moscow Region, Russia, 142290
| | - V V Klimov
- Institute of Basic Biological Problems, Russian Academy of Sciences, Pushchino, Moscow Region, Russia, 142290
| |
Collapse
|
14
|
Singh R, Parihar P, Singh S, Mishra RK, Singh VP, Prasad SM. Reactive oxygen species signaling and stomatal movement: Current updates and future perspectives. Redox Biol 2017; 11:213-218. [PMID: 28012436 PMCID: PMC5192041 DOI: 10.1016/j.redox.2016.11.006] [Citation(s) in RCA: 83] [Impact Index Per Article: 11.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2016] [Revised: 11/09/2016] [Accepted: 11/10/2016] [Indexed: 12/27/2022] Open
Abstract
Reactive oxygen species (ROS), a by-product of aerobic metabolism were initially studied in context to their damaging effect but recent decades witnessed significant advancements in understanding the role of ROS as signaling molecules. Contrary to earlier views, it is becoming evident that ROS production is not necessarily a symptom of cellular dysfunction but it might represent a necessary signal in adjusting the cellular machinery according to the altered conditions. Stomatal movement is controlled by multifaceted signaling network in response to endogenous and environmental signals. Furthermore, the stomatal aperture is regulated by a coordinated action of signaling proteins, ROS-generating enzymes, and downstream executors like transporters, ion pumps, plasma membrane channels, which control the turgor pressure of the guard cell. The earliest hallmarks of stomatal closure are ROS accumulation in the apoplast and chloroplasts and thereafter, there is a successive increase in cytoplasmic Ca2+ level which rules the multiple kinases activity that in turn regulates the activity of ROS-generating enzymes and various ion channels. In addition, ROS also regulate the action of multiple proteins directly by oxidative post translational modifications to adjust guard cell signaling. Notwithstanding, an active progress has been made with ROS signaling mechanism but the regulatory action for ROS signaling processes in stomatal movement is still fragmentary. Therefore, keeping in view the above facts, in this mini review the basic concepts and role of ROS signaling in the stomatal movement have been presented comprehensively along with recent highlights.
Collapse
Affiliation(s)
- Rachana Singh
- Ranjan Plant Physiology and Biochemistry Laboratory, Department of Botany, University of Allahabad, Allahabad 211002, India
| | - Parul Parihar
- Ranjan Plant Physiology and Biochemistry Laboratory, Department of Botany, University of Allahabad, Allahabad 211002, India
| | - Samiksha Singh
- Ranjan Plant Physiology and Biochemistry Laboratory, Department of Botany, University of Allahabad, Allahabad 211002, India
| | - Rohit Kumar Mishra
- Ranjan Plant Physiology and Biochemistry Laboratory, Department of Botany, University of Allahabad, Allahabad 211002, India
| | - Vijay Pratap Singh
- Govt. Ramanuj Pratap Singhdev Post Graduate College, Baikunthpur, Koriya 497335, Chhattisgarh, India.
| | - Sheo Mohan Prasad
- Ranjan Plant Physiology and Biochemistry Laboratory, Department of Botany, University of Allahabad, Allahabad 211002, India.
| |
Collapse
|
15
|
Production of superoxide from photosystem II-light harvesting complex II supercomplex in STN8 kinase knock-out rice mutants under photoinhibitory illumination. JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY B-BIOLOGY 2016; 162:240-247. [PMID: 27390892 DOI: 10.1016/j.jphotobiol.2016.06.050] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/05/2016] [Accepted: 06/28/2016] [Indexed: 01/19/2023]
Abstract
When phosphorylation of Photosystem (PS) II core proteins is blocked in STN8 knock-out mutants of rice (Oryza sativa) under photoinhibitory illumination, the mobilization of PSII supercomplex is prevented. We have previously proposed that more superoxide (O2(-)) is produced from PSII in the mutant (Nath et al., 2013, Plant J. 76, 675-686). Here, we clarify the type and site for the generation of reactive oxygen species (ROS). Using both histochemical and fluorescence probes, we observed that, compared with wild-type (WT) leaves, levels of ROS, including O2(-) and hydrogen peroxide (H2O2), were increased when leaves from mutant plants were illuminated with excess light. However, singlet oxygen production was not enhanced under such conditions. When superoxide dismutase was inhibited, O2(-) production was increased, indicating that it is the initial event prior to H2O2 production. In thylakoids isolated from WT leaves, kinase was active in the presence of ATP, and spectrophotometric analysis of nitrobluetetrazolium absorbance for O2(-) confirmed that PSII-driven superoxide production was greater in the mutant thylakoids than in the WT. This contrast in levels of PSII-driven superoxide production between the mutants and the WT plants was confirmed by conducting protein oxidation assays of PSII particles from osstn8 leaves under strong illumination. Those assays also demonstrated that PSII-LHCII supercomplex proteins were oxidized more in the mutant, thereby implying that PSII particles incur greater damage even though D1 degradation during PSII-supercomplex mobilization is partially blocked in the mutant. These results suggest that O2(-) is the major form of ROS produced in the mutant, and that the damaged PSII in the supercomplex is the primary source of O2(-).
Collapse
|
16
|
Mignolet-Spruyt L, Xu E, Idänheimo N, Hoeberichts FA, Mühlenbock P, Brosché M, Van Breusegem F, Kangasjärvi J. Spreading the news: subcellular and organellar reactive oxygen species production and signalling. JOURNAL OF EXPERIMENTAL BOTANY 2016; 67:3831-44. [PMID: 26976816 DOI: 10.1093/jxb/erw080] [Citation(s) in RCA: 231] [Impact Index Per Article: 28.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/18/2023]
Abstract
As plants are sessile organisms that have to attune their physiology and morphology continuously to varying environmental challenges in order to survive and reproduce, they have evolved complex and integrated environment-cell, cell-cell, and cell-organelle signalling circuits that regulate and trigger the required adjustments (such as alteration of gene expression). Although reactive oxygen species (ROS) are essential components of this network, their pathways are not yet completely unravelled. In addition to the intrinsic chemical properties that define the array of interaction partners, mobility, and stability, ROS signalling specificity is obtained via the spatiotemporal control of production and scavenging at different organellar and subcellular locations (e.g. chloroplasts, mitochondria, peroxisomes, and apoplast). Furthermore, these cellular compartments may crosstalk to relay and further fine-tune the ROS message. Hence, plant cells might locally and systemically react upon environmental or developmental challenges by generating spatiotemporally controlled dosages of certain ROS types, each with specific chemical properties and interaction targets, that are influenced by interorganellar communication and by the subcellular location and distribution of the involved organelles, to trigger the suitable acclimation responses in association with other well-established cellular signalling components (e.g. reactive nitrogen species, phytohormones, and calcium ions). Further characterization of this comprehensive ROS signalling matrix may result in the identification of new targets and key regulators of ROS signalling, which might be excellent candidates for engineering or breeding stress-tolerant plants.
Collapse
Affiliation(s)
- Lorin Mignolet-Spruyt
- Department of Plant Systems Biology, VIB, 9052 Ghent, Belgium Department of Plant Biotechnology and Bioinformatics, Ghent University, 9052 Ghent, Belgium
| | - Enjun Xu
- Division of Plant Biology, Viikki Plant Science Centre, Department of Biosciences, 00014 University of Helsinki, Finland
| | - Niina Idänheimo
- Division of Plant Biology, Viikki Plant Science Centre, Department of Biosciences, 00014 University of Helsinki, Finland
| | - Frank A Hoeberichts
- Department of Plant Systems Biology, VIB, 9052 Ghent, Belgium Department of Plant Biotechnology and Bioinformatics, Ghent University, 9052 Ghent, Belgium
| | - Per Mühlenbock
- Department of Plant Systems Biology, VIB, 9052 Ghent, Belgium Department of Plant Biotechnology and Bioinformatics, Ghent University, 9052 Ghent, Belgium
| | - Mikael Brosché
- Division of Plant Biology, Viikki Plant Science Centre, Department of Biosciences, 00014 University of Helsinki, Finland
| | - Frank Van Breusegem
- Department of Plant Systems Biology, VIB, 9052 Ghent, Belgium Department of Plant Biotechnology and Bioinformatics, Ghent University, 9052 Ghent, Belgium
| | - Jaakko Kangasjärvi
- Division of Plant Biology, Viikki Plant Science Centre, Department of Biosciences, 00014 University of Helsinki, Finland Distinguished Scientist Fellowship Program, College of Science, King Saud University, Riyadh, Saudi Arabia
| |
Collapse
|
17
|
Hossain MS, Dietz KJ. Tuning of Redox Regulatory Mechanisms, Reactive Oxygen Species and Redox Homeostasis under Salinity Stress. FRONTIERS IN PLANT SCIENCE 2016; 7:548. [PMID: 27242807 PMCID: PMC4861717 DOI: 10.3389/fpls.2016.00548] [Citation(s) in RCA: 130] [Impact Index Per Article: 16.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/28/2016] [Accepted: 04/08/2016] [Indexed: 05/17/2023]
Abstract
Soil salinity is a crucial environmental constraint which limits biomass production at many sites on a global scale. Saline growth conditions cause osmotic and ionic imbalances, oxidative stress and perturb metabolism, e.g., the photosynthetic electron flow. The plant ability to tolerate salinity is determined by multiple biochemical and physiological mechanisms protecting cell functions, in particular by regulating proper water relations and maintaining ion homeostasis. Redox homeostasis is a fundamental cell property. Its regulation includes control of reactive oxygen species (ROS) generation, sensing deviation from and readjustment of the cellular redox state. All these redox related functions have been recognized as decisive factors in salinity acclimation and adaptation. This review focuses on the core response of plants to overcome the challenges of salinity stress through regulation of ROS generation and detoxification systems and to maintain redox homeostasis. Emphasis is given to the role of NADH oxidase (RBOH), alternative oxidase (AOX), the plastid terminal oxidase (PTOX) and the malate valve with the malate dehydrogenase isoforms under salt stress. Overwhelming evidence assigns an essential auxiliary function of ROS and redox homeostasis to salinity acclimation of plants.
Collapse
Affiliation(s)
| | - Karl-Josef Dietz
- Department of Biochemistry and Physiology of Plants, Faculty of Biology, University of BielefeldBielefeld, Germany
| |
Collapse
|
18
|
Chen HC, Williams RM, Reek JNH, Brouwer AM. Robust Benzo[g, h, i ]perylenetriimide Dye-Sensitized Electrodes in Air-Saturated Aqueous Buffer Solution. Chemistry 2016; 22:5489-93. [DOI: 10.1002/chem.201505146] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2015] [Indexed: 01/07/2023]
Affiliation(s)
- Hung-Cheng Chen
- University of Amsterdam; Van‘t Hoff Institute for Molecular Sciences; P.O. Box 94157 1090 GD Amsterdam The Netherlands
| | - René M. Williams
- University of Amsterdam; Van‘t Hoff Institute for Molecular Sciences; P.O. Box 94157 1090 GD Amsterdam The Netherlands
| | - Joost N. H. Reek
- University of Amsterdam; Van‘t Hoff Institute for Molecular Sciences; P.O. Box 94157 1090 GD Amsterdam The Netherlands
| | - Albert M. Brouwer
- University of Amsterdam; Van‘t Hoff Institute for Molecular Sciences; P.O. Box 94157 1090 GD Amsterdam The Netherlands
| |
Collapse
|
19
|
Pospíšil P. Production of Reactive Oxygen Species by Photosystem II as a Response to Light and Temperature Stress. FRONTIERS IN PLANT SCIENCE 2016; 7:1950. [PMID: 28082998 PMCID: PMC5183610 DOI: 10.3389/fpls.2016.01950] [Citation(s) in RCA: 197] [Impact Index Per Article: 24.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/23/2016] [Accepted: 12/07/2016] [Indexed: 05/19/2023]
Abstract
The effect of various abiotic stresses on photosynthetic apparatus is inevitably associated with formation of harmful reactive oxygen species (ROS). In this review, recent progress on ROS production by photosystem II (PSII) as a response to high light and high temperature is overviewed. Under high light, ROS production is unavoidably associated with energy transfer and electron transport in PSII. Singlet oxygen is produced by the energy transfer form triplet chlorophyll to molecular oxygen formed by the intersystem crossing from singlet chlorophyll in the PSII antennae complex or the recombination of the charge separated radical pair in the PSII reaction center. Apart to triplet chlorophyll, triplet carbonyl formed by lipid peroxidation transfers energy to molecular oxygen forming singlet oxygen. On the PSII electron acceptor side, electron leakage to molecular oxygen forms superoxide anion radical which dismutes to hydrogen peroxide which is reduced by the non-heme iron to hydroxyl radical. On the PSII electron donor side, incomplete water oxidation forms hydrogen peroxide which is reduced by manganese to hydroxyl radical. Under high temperature, dark production of singlet oxygen results from lipid peroxidation initiated by lipoxygenase, whereas incomplete water oxidation forms hydrogen peroxide which is reduced by manganese to hydroxyl radical. The understanding of molecular basis for ROS production by PSII provides new insight into how plants survive under adverse environmental conditions.
Collapse
|
20
|
Pospíšil P. Production of Reactive Oxygen Species by Photosystem II as a Response to Light and Temperature Stress. FRONTIERS IN PLANT SCIENCE 2016; 7:1950. [PMID: 28082998 DOI: 10.3389/fpls.2016.01950/abstract] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 09/23/2016] [Accepted: 12/07/2016] [Indexed: 05/20/2023]
Abstract
The effect of various abiotic stresses on photosynthetic apparatus is inevitably associated with formation of harmful reactive oxygen species (ROS). In this review, recent progress on ROS production by photosystem II (PSII) as a response to high light and high temperature is overviewed. Under high light, ROS production is unavoidably associated with energy transfer and electron transport in PSII. Singlet oxygen is produced by the energy transfer form triplet chlorophyll to molecular oxygen formed by the intersystem crossing from singlet chlorophyll in the PSII antennae complex or the recombination of the charge separated radical pair in the PSII reaction center. Apart to triplet chlorophyll, triplet carbonyl formed by lipid peroxidation transfers energy to molecular oxygen forming singlet oxygen. On the PSII electron acceptor side, electron leakage to molecular oxygen forms superoxide anion radical which dismutes to hydrogen peroxide which is reduced by the non-heme iron to hydroxyl radical. On the PSII electron donor side, incomplete water oxidation forms hydrogen peroxide which is reduced by manganese to hydroxyl radical. Under high temperature, dark production of singlet oxygen results from lipid peroxidation initiated by lipoxygenase, whereas incomplete water oxidation forms hydrogen peroxide which is reduced by manganese to hydroxyl radical. The understanding of molecular basis for ROS production by PSII provides new insight into how plants survive under adverse environmental conditions.
Collapse
Affiliation(s)
- Pavel Pospíšil
- Department of Biophysics, Centre of the Region Haná for Biotechnological and Agricultural Research, Faculty of Science, Palacký University Olomouc, Czechia
| |
Collapse
|
21
|
Prasad A, Kumar A, Suzuki M, Kikuchi H, Sugai T, Kobayashi M, Pospíšil P, Tada M, Kasai S. Detection of hydrogen peroxide in Photosystem II (PSII) using catalytic amperometric biosensor. FRONTIERS IN PLANT SCIENCE 2015; 6:862. [PMID: 26528319 PMCID: PMC4606053 DOI: 10.3389/fpls.2015.00862] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/27/2015] [Accepted: 09/29/2015] [Indexed: 05/29/2023]
Abstract
Hydrogen peroxide (H2O2) is known to be generated in Photosystem II (PSII) via enzymatic and non-enzymatic pathways. Detection of H2O2 by different spectroscopic techniques has been explored, however its sensitive detection has always been a challenge in photosynthetic research. During the recent past, fluorescence probes such as Amplex Red (AR) has been used but is known to either lack specificity or limitation with respect to the minimum detection limit of H2O2. We have employed an electrochemical biosensor for real time monitoring of H2O2 generation at the level of sub-cellular organelles. The electrochemical biosensor comprises of counter electrode and working electrodes. The counter electrode is a platinum plate, while the working electrode is a mediator based catalytic amperometric biosensor device developed by the coating of a carbon electrode with osmium-horseradish peroxidase which acts as H2O2 detection sensor. In the current study, generation and kinetic behavior of H2O2 in PSII membranes have been studied under light illumination. Electrochemical detection of H2O2 using the catalytic amperometric biosensor device is claimed to serve as a promising technique for detection of H2O2 in photosynthetic cells and subcellular structures including PSII or thylakoid membranes. It can also provide a precise information on qualitative determination of H2O2 and thus can be widely used in photosynthetic research.
Collapse
Affiliation(s)
- Ankush Prasad
- Biomedical Engineering Research Center, Tohoku Institute of TechnologySendai, Japan
| | - Aditya Kumar
- Department of Biophysics, Faculty of Science, Centre of the Region Haná for Biotechnological and Agricultural Research, Palacký UniversityOlomouc, Czech Republic
| | - Makoto Suzuki
- Graduate Department of Environmental Information Engineering, Tohoku Institute of TechnologySendai, Japan
| | - Hiroyuki Kikuchi
- Graduate Department of Environmental Information Engineering, Tohoku Institute of TechnologySendai, Japan
| | - Tomoya Sugai
- Graduate Department of Environmental Information Engineering, Tohoku Institute of TechnologySendai, Japan
| | - Masaki Kobayashi
- Biomedical Engineering Research Center, Tohoku Institute of TechnologySendai, Japan
- Graduate Department of Electronics, Tohoku Institute of TechnologySendai, Japan
| | - Pavel Pospíšil
- Department of Biophysics, Faculty of Science, Centre of the Region Haná for Biotechnological and Agricultural Research, Palacký UniversityOlomouc, Czech Republic
| | - Mika Tada
- Biomedical Engineering Research Center, Tohoku Institute of TechnologySendai, Japan
- Center for General Education, Tohoku Institute of TechnologySendai, Japan
| | - Shigenobu Kasai
- Biomedical Engineering Research Center, Tohoku Institute of TechnologySendai, Japan
- Graduate Department of Environmental Information Engineering, Tohoku Institute of TechnologySendai, Japan
| |
Collapse
|
22
|
Trehalose stimulation of photoinduced electron transfer and oxygen photoconsumption in Mn-depleted photosystem 2 membrane fragments. JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY B-BIOLOGY 2015; 152:279-85. [PMID: 26386978 DOI: 10.1016/j.jphotobiol.2015.08.033] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/16/2015] [Revised: 08/20/2015] [Accepted: 08/21/2015] [Indexed: 11/21/2022]
Abstract
It is known that the removal of manganese from the water-oxidizing complex (WOC) of photosystem 2 (PS2) leads to activation of oxygen photoconsumption (OPC) [Khorobrykh et al., 2002; Yanykin et al., 2010] that is accompanied by the formation of organic hydroperoxides on the electron-donor side of PS2 [Khorobrykh et al., 2011]. In the present work the effect of trehalose on the OPC in Mn-depleted PS2 preparations (apo-WOC-PS2) was investigated. A more than two-fold increase of the OPC is revealed upon the addition of 1M trehalose. Drastic (30%-70%) inhibition of the OPC upon the addition of either electron acceptor or electron donor indicates that the trehalose-induced activation of the OPC occurs on both donor and acceptor sides of PS2. A two-fold increase in the rate of superoxide-anion radical photoproduction on the electron-acceptor side of PS2 was also shown. Applying the "variable" chlorophyll fluorescence (ΔF) it was shown that the addition of trehalose induces: (i) a significant increase in the ability of exogenous Mn(2+) to donate electrons to the reaction center of PS2, (ii) slowing down the photoaccumulation of the primary quinone electron acceptor of PS2 (QA(-)) under aerobic conditions, (iii) acceleration of the reoxidation of QA(-) by QB (and by QB(-)) as well as the replacement of QB(2-) by a fully oxidized plastoquinone, and (iv) restoration of the electron transfer between the quinone electron carriers in the so-called "closed reaction centers of PS2" (their content in the apo-WOC-PS2 is 41%). It is suggested that the trehalose-induced increase in efficiency of the O2 interaction with the electron-donor and electron-acceptor sides of apo-WOC-PS2 is due to structural changes leading to both a decrease in the proportion of the "closed PS2 reaction centers" and an increase in the electron transfer rate in PS2.
Collapse
|
23
|
Ostaszewska-Bugajska M, Rychter AM, Juszczuk IM. Antioxidative and proteolytic systems protect mitochondria from oxidative damage in S-deficient Arabidopsis thaliana. JOURNAL OF PLANT PHYSIOLOGY 2015; 186-187:25-38. [PMID: 26339750 DOI: 10.1016/j.jplph.2015.07.011] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/21/2015] [Revised: 07/15/2015] [Accepted: 07/17/2015] [Indexed: 06/05/2023]
Abstract
We examined the functioning of the antioxidative defense system in Arabidopsis thaliana under sulphur (S) deficiency with an emphasis on the role of mitochondria. In tissue extracts and in isolated mitochondria from S-deficient plants, the concentration of non-protein thiols declined but protein thiols did not change. Superoxide anion and hydrogen peroxide were accumulated in leaf blades and the generation of superoxide anion by isolated mitochondria was higher. Lower abundance of reduced (GSH) plus oxidized (GSSG) glutathione in the leaf and root tissues, and leaf mitochondria from S-deficient plants was accompanied by a decrease in the level of GSH and the changes in the GSH/GSSG ratios. In the chloroplasts, the total level of glutathione decreased. Lower levels of reduced (AsA) and oxidized (DHA) ascorbate were reflected in much higher ratios of AsA/DHA. Sulphur deficiency led to an increase in the activity of cytosolic, mitochondrial and chloroplastic antioxidative enzymes, peroxidases, catalases and superoxide dismutases. The protein carbonyl level was higher in the leaves of S-deficient plants and in the chloroplasts, while in the roots, leaf and root mitochondria it remained unchanged. Protease activity in leaf extracts of S-deficient plants was higher, but in root extracts it did not differ. The proteolytic system reflected subcellular specificity. In leaf and root mitochondria the protease activity was higher, whereas in the chloroplasts it did not change. We propose that the preferential incorporation of S to protein thiols and activation of antioxidative and proteolytic systems are likely important for the survival of S-deficient plants and that the mitochondria maintain redox homeostasis.
Collapse
Affiliation(s)
- Monika Ostaszewska-Bugajska
- Institute of Experimental Plant Biology and Biotechnology, Faculty of Biology, University of Warsaw, Poland.
| | - Anna M Rychter
- Institute of Experimental Plant Biology and Biotechnology, Faculty of Biology, University of Warsaw, Poland.
| | - Izabela M Juszczuk
- Institute of Experimental Plant Biology and Biotechnology, Faculty of Biology, University of Warsaw, Poland.
| |
Collapse
|
24
|
Khorobrykh SA, Karonen M, Tyystjärvi E. Experimental evidence suggesting that H2O2 is produced within the thylakoid membrane in a reaction between plastoquinol and singlet oxygen. FEBS Lett 2015; 589:779-86. [PMID: 25701589 DOI: 10.1016/j.febslet.2015.02.011] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2014] [Revised: 01/30/2015] [Accepted: 02/10/2015] [Indexed: 10/24/2022]
Abstract
Plastoquinol (PQH2-9) and plastoquinone (PQ-9) mediate photosynthetic electron transfer. We isolated PQH2-9 from thylakoid membranes, purified it with HPLC, subjected the purified PQH2-9 to singlet oxygen ((1)O2) and analyzed the products. The main reaction of (1)O2 with PQH2-9 in methanol was found to result in formation of PQ-9 and H2O2, and the amount of H2O2 produced was essentially the same as the amount of oxidized PQH2-9. Formation of H2O2 in the reaction between (1)O2 and PQH2-9 may be an important source of H2O2 within the lipophilic thylakoid membrane.
Collapse
Affiliation(s)
- Sergey A Khorobrykh
- Department of Biochemistry/Molecular Plant Biology, University of Turku, FI-20014 Turku, Finland
| | - Maarit Karonen
- Laboratory of Organic Chemistry and Chemical Biology, Department of Chemistry, University of Turku, FI-20014 Turku, Finland
| | - Esa Tyystjärvi
- Department of Biochemistry/Molecular Plant Biology, University of Turku, FI-20014 Turku, Finland.
| |
Collapse
|
25
|
Yadav DK, Prasad A, Kruk J, Pospíšil P. Evidence for the involvement of loosely bound plastosemiquinones in superoxide anion radical production in photosystem II. PLoS One 2014; 9:e115466. [PMID: 25541694 PMCID: PMC4277363 DOI: 10.1371/journal.pone.0115466] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2014] [Accepted: 11/24/2014] [Indexed: 11/22/2022] Open
Abstract
Recent evidence has indicated the presence of novel plastoquinone-binding sites, QC and QD, in photosystem II (PSII). Here, we investigated the potential involvement of loosely bound plastosemiquinones in superoxide anion radical (O2•−) formation in spinach PSII membranes using electron paramagnetic resonance (EPR) spin-trapping spectroscopy. Illumination of PSII membranes in the presence of the spin trap EMPO (5-(ethoxycarbonyl)-5-methyl-1-pyrroline N-oxide) resulted in the formation of O2•−, which was monitored by the appearance of EMPO-OOH adduct EPR signal. Addition of exogenous short-chain plastoquinone to PSII membranes markedly enhanced the EMPO-OOH adduct EPR signal. Both in the unsupplemented and plastoquinone-supplemented PSII membranes, the EMPO-OOH adduct EPR signal was suppressed by 50% when the urea-type herbicide DCMU (3-(3,4-dichlorophenyl)-1,1-dimethylurea) was bound at the QB site. However, the EMPO-OOH adduct EPR signal was enhanced by binding of the phenolic-type herbicide dinoseb (2,4-dinitro-6-sec-butylphenol) at the QD site. Both in the unsupplemented and plastoquinone-supplemented PSII membranes, DCMU and dinoseb inhibited photoreduction of the high-potential form of cytochrome b559 (cyt b559). Based on these results, we propose that O2•− is formed via the reduction of molecular oxygen by plastosemiquinones formed through one-electron reduction of plastoquinone at the QB site and one-electron oxidation of plastoquinol by cyt b559 at the QC site. On the contrary, the involvement of a plastosemiquinone formed via the one-electron oxidation of plastoquinol by cyt b559 at the QD site seems to be ambiguous. In spite of the fact that the existence of QC and QD sites is not generally accepted yet, the present study provided more spectroscopic data on the potential functional role of these new plastoquinone-binding sites.
Collapse
Affiliation(s)
- Deepak Kumar Yadav
- Department of Biophysics, Centre of the Region Haná for Biotechnological and Agricultural Research, Faculty of Science, Palacký University, Olomouc, Czech Republic
| | - Ankush Prasad
- Department of Biophysics, Centre of the Region Haná for Biotechnological and Agricultural Research, Faculty of Science, Palacký University, Olomouc, Czech Republic
| | - Jerzy Kruk
- Department of Plant Physiology and Biochemistry, Faculty of Biochemistry, Biophysics and Biotechnology, Jagiellonian University, Kraków, Poland
| | - Pavel Pospíšil
- Department of Biophysics, Centre of the Region Haná for Biotechnological and Agricultural Research, Faculty of Science, Palacký University, Olomouc, Czech Republic
- * E-mail:
| |
Collapse
|
26
|
Schmidt R, Schippers JHM. ROS-mediated redox signaling during cell differentiation in plants. Biochim Biophys Acta Gen Subj 2014; 1850:1497-508. [PMID: 25542301 DOI: 10.1016/j.bbagen.2014.12.020] [Citation(s) in RCA: 50] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2014] [Revised: 12/18/2014] [Accepted: 12/19/2014] [Indexed: 12/19/2022]
Abstract
BACKGROUND Reactive oxygen species (ROS) have emerged in recent years as important regulators of cell division and differentiation. SCOPE OF REVIEW The cellular redox state has a major impact on cell fate and multicellular organism development. However, the exact molecular mechanisms through which ROS manifest their regulation over cellular development are only starting to be understood in plants. ROS levels are constantly monitored and any change in the redox pool is rapidly sensed and responded upon. Different types of ROS cause specific oxidative modifications, providing the basic characteristics of a signaling molecule. Here we provide an overview of ROS sensors and signaling cascades that regulate transcriptional responses in plants to guide cellular differentiation and organ development. MAJOR CONCLUSIONS Although several redox sensors and cascades have been identified, they represent only a first glimpse on the impact that redox signaling has on plant development and growth. GENERAL SIGNIFICANCE We provide an initial evaluation of ROS signaling cascades involved in cell differentiation in plants and identify potential avenues for future studies. This article is part of a Special Issue entitled Redox regulation of differentiation and de-differentiation.
Collapse
Affiliation(s)
- Romy Schmidt
- Institute of Biology I, RWTH Aachen University, Worringerweg 1, 52074 Aachen, Germany
| | - Jos H M Schippers
- Institute of Biology I, RWTH Aachen University, Worringerweg 1, 52074 Aachen, Germany.
| |
Collapse
|
27
|
Zulfugarov IS, Tovuu A, Eu YJ, Dogsom B, Poudyal RS, Nath K, Hall M, Banerjee M, Yoon UC, Moon YH, An G, Jansson S, Lee CH. Production of superoxide from Photosystem II in a rice (Oryza sativa L.) mutant lacking PsbS. BMC PLANT BIOLOGY 2014; 14:242. [PMID: 25342550 PMCID: PMC4219129 DOI: 10.1186/s12870-014-0242-2] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/24/2014] [Accepted: 09/08/2014] [Indexed: 05/05/2023]
Abstract
BACKGROUND PsbS is a 22-kDa Photosystem (PS) II protein involved in non-photochemical quenching (NPQ) of chlorophyll fluorescence. Rice (Oryza sativa L.) has two PsbS genes, PsbS1 and PsbS2. However, only inactivation of PsbS1, through a knockout (PsbS1-KO) or in RNAi transgenic plants, results in plants deficient in qE, the energy-dependent component of NPQ. RESULTS In studies presented here, under fluctuating high light, growth of young seedlings lacking PsbS is retarded, and PSII in detached leaves of the mutants is more sensitive to photoinhibitory illumination compared with the wild type. Using both histochemical and fluorescent probes, we determined the levels of reactive oxygen species, including singlet oxygen, superoxide, and hydrogen peroxide, in leaves and thylakoids. The PsbS-deficient plants generated more superoxide and hydrogen peroxide in their chloroplasts. PSII complexes isolated from them produced more superoxide compared with the wild type, and PSII-driven superoxide production was higher in the mutants. However, we could not observe such differences either in isolated PSI complexes or through PSI-driven electron transport. Time-course experiments using isolated thylakoids showed that superoxide production was the initial event, and that production of hydrogen peroxide proceeded from that. CONCLUSION These results indicate that at least some of the photoprotection provided by PsbS and qE is mediated by preventing production of superoxide released from PSII under conditions of excess excitation energy.
Collapse
Affiliation(s)
- Ismayil S Zulfugarov
- />Department of Integrated Biological Science and Department of Molecular Biology, Pusan National University, Busan, 609-735 Korea
- />Department of Biology, North-Eastern Federal University, 58 Belinsky Str, Yakutsk, 677-027 Republic of Sakha (Yakutia) Russian Federation
- />Institute of Botany, Azerbaijan National Academy of Sciences, Patamdar Shosse 40, Baku, AZ 1073 Azerbaijan
| | - Altanzaya Tovuu
- />Department of Integrated Biological Science and Department of Molecular Biology, Pusan National University, Busan, 609-735 Korea
- />Department of Biology, Mongolian State University of Agriculture, Zaisan, Ulaanbaatar, 17024 Mongolia
| | - Young-Jae Eu
- />Department of Integrated Biological Science and Department of Molecular Biology, Pusan National University, Busan, 609-735 Korea
| | - Bolormaa Dogsom
- />Department of Integrated Biological Science and Department of Molecular Biology, Pusan National University, Busan, 609-735 Korea
| | - Roshan Sharma Poudyal
- />Department of Integrated Biological Science and Department of Molecular Biology, Pusan National University, Busan, 609-735 Korea
| | - Krishna Nath
- />Department of Integrated Biological Science and Department of Molecular Biology, Pusan National University, Busan, 609-735 Korea
| | - Michael Hall
- />Umeå Plant Science Center, Department of Plant Physiology, Umeå University, Umeå, SE-901 87 Sweden
| | - Mainak Banerjee
- />Department of Chemistry, Pusan National University, Jangjeon-dong, Keumjung-gu, Busan, 609-735 Korea
| | - Ung Chan Yoon
- />Department of Chemistry, Pusan National University, Jangjeon-dong, Keumjung-gu, Busan, 609-735 Korea
| | - Yong-Hwan Moon
- />Department of Integrated Biological Science and Department of Molecular Biology, Pusan National University, Busan, 609-735 Korea
| | - Gynheung An
- />Crop Biotech Institute, Kyung Hee University, Yongin, 446-701 Korea
| | - Stefan Jansson
- />Umeå Plant Science Center, Department of Plant Physiology, Umeå University, Umeå, SE-901 87 Sweden
| | - Choon-Hwan Lee
- />Department of Integrated Biological Science and Department of Molecular Biology, Pusan National University, Busan, 609-735 Korea
| |
Collapse
|
28
|
Xie X, Gu W, Gao S, Lu S, Li J, Pan G, Wang G, Shen S. Alternative electron transports participate in the maintenance of violaxanthin De-epoxidase activity of Ulva sp. under low irradiance. PLoS One 2013; 8:e78211. [PMID: 24250793 PMCID: PMC3826755 DOI: 10.1371/journal.pone.0078211] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2013] [Accepted: 09/19/2013] [Indexed: 11/18/2022] Open
Abstract
The xanthophyll cycle (Xc), which involves violaxanthin de-epoxidase (VDE) and the zeaxanthin epoxidase (ZEP), is one of the most rapid and efficient responses of plant and algae to high irradiance. High light intensity can activate VDE to convert violaxanthin (Vx) to zeaxanthin (Zx) via antheraxanthin (Ax). However, it remains unclear whether VDE remains active under low light or dark conditions when there is no significant accumulation of Ax and Zx, and if so, how the ΔpH required for activation of VDE is built. In this study, we used salicylaldoxime (SA) to inhibit ZEP activity in the intertidal macro-algae Ulva sp. (Ulvales, Chlorophyta) and then characterized VDE under low light and dark conditions with various metabolic inhibitors. With inhibition of ZEP by SA, VDE remained active under low light and dark conditions, as indicated by large accumulations of Ax and Zx at the expense of Vx. When PSII-mediated linear electron transport systems were completely inhibited by SA and DCMU, alternative electron transport systems (i.e., cyclic electron transport and chlororespiration) could maintain VDE activity. Furthermore, accumulations of Ax and Zx decreased significantly when SA, DCMU, or DBMIB together with an inhibitor of chlororespiration (i.e., propyl gallate (PG)) were applied to Ulva sp. This result suggests that chlororespiration not only participates in the build-up of the necessary ΔpH, but that it also possibly influences VDE activity indirectly by diminishing the oxygen level in the chloroplast.
Collapse
Affiliation(s)
- Xiujun Xie
- Tianjin Key Laboratory of Marine Resources and Chemistry, College of Marine Science and Engineering, Tianjin University of Science and Technology, Tianjin, China
| | - Wenhui Gu
- Institute of Oceanology, Chinese Academy of Sciences, Qingdao, China
- Graduate School, Chinese Academy of Sciences, Beijing, China
| | - Shan Gao
- Institute of Oceanology, Chinese Academy of Sciences, Qingdao, China
- Graduate School, Chinese Academy of Sciences, Beijing, China
| | - Shan Lu
- School of Life Science, Nanjing University, Nanjing, China
| | - Jian Li
- Earth and Life Institute, Catholic University of Louvain, Louvain la Neuve, Belgium
| | - Guanghua Pan
- Tianjin Key Laboratory of Marine Resources and Chemistry, College of Marine Science and Engineering, Tianjin University of Science and Technology, Tianjin, China
| | - Guangce Wang
- Institute of Oceanology, Chinese Academy of Sciences, Qingdao, China
| | - Songdong Shen
- College of Life Sciences, Soochow University, Suzhou, China
| |
Collapse
|
29
|
Nath K, Poudyal RS, Eom JS, Park YS, Zulfugarov IS, Mishra SR, Tovuu A, Ryoo N, Yoon HS, Nam HG, An G, Jeon JS, Lee CH. Loss-of-function of OsSTN8 suppresses the photosystem II core protein phosphorylation and interferes with the photosystem II repair mechanism in rice (Oryza sativa). THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2013; 76:675-86. [PMID: 24103067 DOI: 10.1111/tpj.12331] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/03/2013] [Revised: 08/07/2013] [Accepted: 09/02/2013] [Indexed: 05/10/2023]
Abstract
STN8 kinase is involved in photosystem II (PSII) core protein phosphorylation (PCPP). To examine the role of PCPP in PSII repair during high light (HL) illumination, we characterized a T-DNA insertional knockout mutant of the rice (Oryza sativa) STN8 gene. In this osstn8 mutant, PCPP was significantly suppressed, and the grana were thin and elongated. Upon HL illumination, PSII was strongly inactivated in the mutants, but the D1 protein was degraded more slowly than in wild-type, and mobilization of the PSII supercomplexes from the grana to the stromal lamellae for repair was also suppressed. In addition, higher accumulation of reactive oxygen species and preferential oxidation of PSII reaction center core proteins in thylakoid membranes were observed in the mutants during HL illumination. Taken together, our current data show that the absence of STN8 is sufficient to abolish PCPP in osstn8 mutants and to produce all of the phenotypes observed in the double mutant of Arabidopsis, indicating the essential role of STN8-mediated PCPP in PSII repair.
Collapse
Affiliation(s)
- Krishna Nath
- Department of Molecular Biology, Pusan National University, Busan, 609-735, Korea; Department of New Biology, Daegu Gyeongbuk Institute of Science and Technology, Daegu, 711-873, Korea
| | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
30
|
Semin BK, Davletshina LN, Timofeev KN, Ivanov II, Rubin AB, Seibert M. Production of reactive oxygen species in decoupled, Ca(2+)-depleted PSII and their use in assigning a function to chloride on both sides of PSII. PHOTOSYNTHESIS RESEARCH 2013; 117:385-399. [PMID: 23794169 DOI: 10.1007/s11120-013-9870-x] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/08/2013] [Accepted: 06/07/2013] [Indexed: 06/02/2023]
Abstract
Extraction of Ca(2+) from the oxygen-evolving complex of photosystem II (PSII) in the absence of a chelator inhibits O2 evolution without significant inhibition of the light-dependent reduction of the exogenous electron acceptor, 2,6-dichlorophenolindophenol (DCPIP) on the reducing side of PSII. The phenomenon is known as "the decoupling effect" (Semin et al. Photosynth Res 98:235-249, 2008). Extraction of Cl(-) from Ca(2+)-depleted membranes (PSII[-Ca]) suppresses the reduction of DCPIP. In the current study we investigated the nature of the oxidized substrate and the nature of the product(s) of the substrate oxidation. After elimination of all other possible donors, water was identified as the substrate. Generation of reactive oxygen species HO, H2O2, and O 2 (·-) , as possible products of water oxidation in PSII(-Ca) membranes was examined. During the investigation of O 2 (·-) production in PSII(-Ca) samples, we found that (i) O 2 (·-) is formed on the acceptor side of PSII due to the reduction of O2; (ii) depletion of Cl(-) does not inhibit water oxidation, but (iii) Cl(-) depletion does decrease the efficiency of the reduction of exogenous electron acceptors. In the absence of Cl(-) under aerobic conditions, electron transport is diverted from reducing exogenous acceptors to reducing O2, thereby increasing the rate of O 2 (·-) generation. From these observations we conclude that the product of water oxidation is H2O2 and that Cl(-) anions are not involved in the oxidation of water to H2O2 in decoupled PSII(-Ca) membranes. These results also indicate that Cl(-) anions are not directly involved in water oxidation by the Mn cluster in the native PSII membranes, but possibly provide access for H2O molecules to the Mn4CaO5 cluster and/or facilitate the release of H(+) ions into the lumenal space.
Collapse
Affiliation(s)
- Boris K Semin
- Department of Biophysics, Faculty of Biology, Lomonosov Moscow State University, 119234, Moscow, Russia,
| | | | | | | | | | | |
Collapse
|
31
|
Formation of superoxide anion and carbon-centered radicals by photosystem II under high light and heat stress—EPR spin-trapping study. J Bioenerg Biomembr 2013; 45:551-9. [DOI: 10.1007/s10863-013-9523-y] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2013] [Accepted: 07/19/2013] [Indexed: 10/26/2022]
|
32
|
Chow WS, Fan DY, Oguchi R, Jia H, Losciale P, Park YI, He J, Oquist G, Shen YG, Anderson JM. Quantifying and monitoring functional photosystem II and the stoichiometry of the two photosystems in leaf segments: approaches and approximations. PHOTOSYNTHESIS RESEARCH 2012; 113:63-74. [PMID: 22638914 DOI: 10.1007/s11120-012-9740-y] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/09/2012] [Accepted: 04/04/2012] [Indexed: 05/12/2023]
Abstract
Given its unique function in light-induced water oxidation and its susceptibility to photoinactivation during photosynthesis, photosystem II (PS II) is often the focus of studies of photosynthetic structure and function, particularly in environmental stress conditions. Here we review four approaches for quantifying or monitoring PS II functionality or the stoichiometry of the two photosystems in leaf segments, scrutinizing the approximations in each approach. (1) Chlorophyll fluorescence parameters are convenient to derive, but the information-rich signal suffers from the localized nature of its detection in leaf tissue. (2) The gross O(2) yield per single-turnover flash in CO(2)-enriched air is a more direct measurement of the functional content, assuming that each functional PS II evolves one O(2) molecule after four flashes. However, the gross O(2) yield per single-turnover flash (multiplied by four) could over-estimate the content of functional PS II if mitochondrial respiration is lower in flash illumination than in darkness. (3) The cumulative delivery of electrons from PS II to P700(+) (oxidized primary donor in PS I) after a flash is added to steady background far-red light is a whole-tissue measurement, such that a single linear correlation with functional PS II applies to leaves of all plant species investigated so far. However, the magnitude obtained in a simple analysis (with the signal normalized to the maximum photo-oxidizable P700 signal), which should equal the ratio of PS II to PS I centers, was too small to match the independently-obtained photosystem stoichiometry. Further, an under-estimation of functional PS II content could occur if some electrons were intercepted before reaching PS I. (4) The electrochromic signal from leaf segments appears to reliably quantify the photosystem stoichiometry, either by progressively photoinactivating PS II or suppressing PS I via photo-oxidation of a known fraction of the P700 with steady far-red light. Together, these approaches have the potential for quantitatively probing PS II in vivo in leaf segments, with prospects for application of the latter two approaches in the field.
Collapse
Affiliation(s)
- Wah Soon Chow
- Research School of Biology, College of Medicine, Biology and Environment, The Australian National University, Canberra, ACT, 0200, Australia.
| | | | | | | | | | | | | | | | | | | |
Collapse
|
33
|
Chen L, Jia H, Tian Q, Du L, Gao Y, Miao X, Liu Y. Protecting effect of phosphorylation on oxidative damage of D1 protein by down-regulating the production of superoxide anion in photosystem II membranes under high light. PHOTOSYNTHESIS RESEARCH 2012; 112:141-8. [PMID: 22644478 DOI: 10.1007/s11120-012-9750-9] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/19/2012] [Accepted: 05/14/2012] [Indexed: 05/03/2023]
Abstract
The physiological significance of photosystem II (PSII) core protein phosphorylation has been suggested to facilitate the migration of oxidative damaged D1 and D2 proteins, but meanwhile the phosphorylation seems to be associated with the suppression of reactive oxygen species (ROS) production, and it also relates to the degradation of PSII reaction center proteins. To more clearly elucidate the possible protecting effect of the phosphorylation on oxidative damage of D1 protein, the degradation of oxidized D1 protein and the production of superoxide anion in the non-phosphorylated and phosphorylated PSII membranes were comparatively detected using the Western blotting and electron spin resonance spin-trapping technique, respectively. Obviously, all of three ROS components, including superoxide anion, hydrogen peroxide and hydroxyl radical are responsible for the degradation of oxidized D1 protein, and the protection of the D1 protein degradation by phosphorylation is accompanied by the inhibition of superoxide anion production. Furthermore, the inhibiting effect of 3-(3,4-dichlorophenyl)-1,1-dimethylurea (DCMU), a competitor to Q(B), on superoxide anion production and its protecting effect on D1 protein degradation are even more obvious than those of phosphorylation. Both DCMU effects are independent of whether PSII membranes are phosphorylated or not, which reasonably implies that the herbicide DCMU and D1 protein phosphorylation probably share the same target site in D1 protein of PSII. So, altogether it can be concluded that the phosphorylation of D1 protein reduces the oxidative damage of D1 protein by decreasing the production of superoxide anion in PSII membranes under high light.
Collapse
Affiliation(s)
- Liangbing Chen
- State Key Lab for Structural Chemistry of Unstable and Stable Species, Beijing National Laboratory for Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China
| | | | | | | | | | | | | |
Collapse
|
34
|
Reactive Oxygen Species, Oxidative Damage, and Antioxidative Defense Mechanism in Plants under Stressful Conditions. ACTA ACUST UNITED AC 2012. [DOI: 10.1155/2012/217037] [Citation(s) in RCA: 2231] [Impact Index Per Article: 185.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Reactive oxygen species (ROS) are produced as a normal product of plant cellular metabolism. Various environmental stresses lead to excessive production of ROS causing progressive oxidative damage and ultimately cell death. Despite their destructive activity, they are well-described second messengers in a variety of cellular processes, including conferment of tolerance to various environmental stresses. Whether ROS would serve as signaling molecules or could cause oxidative damage to the tissues depends on the delicate equilibrium between ROS production, and their scavenging. Efficient scavenging of ROS produced during various environmental stresses requires the action of several nonenzymatic as well as enzymatic antioxidants present in the tissues. In this paper, we describe the generation, sites of production and role of ROS as messenger molecules as well as inducers of oxidative damage. Further, the antioxidative defense mechanisms operating in the cells for scavenging of ROS overproduced under various stressful conditions of the environment have been discussed in detail.
Collapse
|
35
|
DING ZS, ZHOU BY, SUN XF, ZHAO M. High Light Tolerance is Enhanced by Overexpressed PEPC in Rice Under Drought Stress. ACTA ACUST UNITED AC 2012. [DOI: 10.1016/s1875-2780(11)60106-5] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
|
36
|
Molecular mechanisms of production and scavenging of reactive oxygen species by photosystem II. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2011; 1817:218-31. [PMID: 21641332 DOI: 10.1016/j.bbabio.2011.05.017] [Citation(s) in RCA: 177] [Impact Index Per Article: 13.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/14/2011] [Revised: 05/07/2011] [Accepted: 05/18/2011] [Indexed: 01/05/2023]
Abstract
Photosystem II (PSII) is a multisubunit protein complex in cyanobacteria, algae and plants that use light energy for oxidation of water and reduction of plastoquinone. The conversion of excitation energy absorbed by chlorophylls into the energy of separated charges and subsequent water-plastoquinone oxidoreductase activity are inadvertently coupled with the formation of reactive oxygen species (ROS). Singlet oxygen is generated by the excitation energy transfer from triplet chlorophyll formed by the intersystem crossing from singlet chlorophyll and the charge recombination of separated charges in the PSII antenna complex and reaction center of PSII, respectively. Apart to the energy transfer, the electron transport associated with the reduction of plastoquinone and the oxidation of water is linked to the formation of superoxide anion radical, hydrogen peroxide and hydroxyl radical. To protect PSII pigments, proteins and lipids against the oxidative damage, PSII evolved a highly efficient antioxidant defense system comprising either a non-enzymatic (prenyllipids such as carotenoids and prenylquinols) or an enzymatic (superoxide dismutase and catalase) scavengers. It is pointed out here that both the formation and the scavenging of ROS are controlled by the energy level and the redox potential of the excitation energy transfer and the electron transport carries, respectively. The review is focused on the mechanistic aspects of ROS production and scavenging by PSII. This article is part of a Special Issue entitled: Photosystem II.
Collapse
|
37
|
Hu X, Tong Z, Lyon LA. Control of poly(N-isopropylacrylamide) microgel network structure by precipitation polymerization near the lower critical solution temperature. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2011; 27:4142-4148. [PMID: 21401062 PMCID: PMC3068749 DOI: 10.1021/la200114s] [Citation(s) in RCA: 64] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
Poly(N-isopropylacrylamide) (pNIPAm) microgels were synthesized by precipitation polymerization at temperatures ranging from 37 to 45 °C using redox initiator system ammonium persulfate (APS)/N,N,N',N'-tetramethylethylenediamine (TEMED) or photoinitiator 2,2'-azobis(amidinopropane) dihydrochloride (V50). Photon correlation spectroscopy (PCS) and atomic force microscopy (AFM) studies revealed that spherical microgels with narrow size dispersities can be obtained with these methods and that the resultant microgels have volume phase transition behaviors expected from their compositions. Additionally, the low-temperature redox initiator strategy produces microgels devoid of self-cross-linking, thereby permitting the synthesis of completely degradable microgels when using N,N'-(1,2-dihydroxyethylene)bisacrylamide (DHEA) as a cleavable cross-linker. We also demonstrate the potential utility of the approach in bioconjugate syntheses; in this case, avidin immobilization is demonstrated by one-pot copolymerization at low temperature.
Collapse
Affiliation(s)
- Xiaobo Hu
- School of Chemistry & Biochemistry and the Petit Institute for Bioengineering & Bioscience, Georgia Institute of Technology, Atlanta, GA 30332, USA
- Research Institute of Materials Science, South China University of Technology, Guangzhou 510640, P. R. China
| | - Zhen Tong
- Research Institute of Materials Science, South China University of Technology, Guangzhou 510640, P. R. China
| | - L. Andrew Lyon
- School of Chemistry & Biochemistry and the Petit Institute for Bioengineering & Bioscience, Georgia Institute of Technology, Atlanta, GA 30332, USA
| |
Collapse
|
38
|
Nonlinear dielectric spectroscopy as an indirect probe of metabolic activity in thylakoid membrane. BIOSENSORS-BASEL 2011; 1:13-22. [PMID: 25586698 PMCID: PMC4264345 DOI: 10.3390/bios1010013] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/08/2010] [Revised: 12/29/2010] [Accepted: 01/27/2011] [Indexed: 11/16/2022]
Abstract
Nonlinear dielectric spectroscopy (NDS) is a non-invasive probe of cellular metabolic activity with potential application in the development of whole-cell biosensors. However, the mechanism of NDS interaction with metabolic membrane proteins is poorly understood, partly due to the inherent complexity of single cell organisms. Here we use the light-activated electron transport chain of spinach thylakoid membrane as a model system to study how NDS interacts with metabolic activity. We find protein modification, as opposed to membrane pump activity, to be the dominant source of NDS signal change in this system. Potential mechanisms for such protein modifications include reactive oxygen species generation and light-activated phosphorylation.
Collapse
|
39
|
Ivanov BN. Cooperation of photosystem I with the plastoquinone pool in oxygen reduction in higher plant chloroplasts. BIOCHEMISTRY (MOSCOW) 2011; 73:112-8. [DOI: 10.1134/s0006297908010173] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
|
40
|
Mubarakshina MM, Ivanov BN. The production and scavenging of reactive oxygen species in the plastoquinone pool of chloroplast thylakoid membranes. PHYSIOLOGIA PLANTARUM 2010; 140:103-10. [PMID: 20553418 DOI: 10.1111/j.1399-3054.2010.01391.x] [Citation(s) in RCA: 72] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/08/2023]
Abstract
Reactive oxygen species (ROS) resulting from oxygen reduction, superoxide anion radical O2(*-) and hydrogen peroxide H(2)O(2) are very significant in the cell metabolism of aerobic organisms. They can be destructive and lead to apoptosis and they can also serve as signal molecules. In the light, chloroplasts are known to be one of the main sources of ROS in plants. However, the components involved in oxygen reduction and the detailed chemical mechanism are not yet well established. The present review describes the experimental data and theoretical considerations that implicate the plastoquinone pool (PQ-pool) in this process. The evidence indicates that the PQ-pool has a dual role: (1) the reduction of O(2) by plastosemiquinone to superoxide and (2) the reduction of superoxide by plastohydroquinone to hydrogen peroxide. The second role represents not only the scavenging of superoxide, but also the generation of hydrogen peroxide as an important signaling molecule. The regulatory and protective functions of the PQ-pool are discussed in the context of these reactions.
Collapse
Affiliation(s)
- Maria M Mubarakshina
- Institute of Basic Biological Problems, Russian Academy of Sciences, Pushchino, Russia
| | | |
Collapse
|
41
|
Chen S, Yin C, Qiang S, Zhou F, Dai X. Chloroplastic oxidative burst induced by tenuazonic acid, a natural photosynthesis inhibitor, triggers cell necrosis in Eupatorium adenophorum Spreng. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2009; 1797:391-405. [PMID: 20026008 DOI: 10.1016/j.bbabio.2009.12.007] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/12/2009] [Revised: 12/08/2009] [Accepted: 12/14/2009] [Indexed: 01/15/2023]
Abstract
Tenuazonic acid (TeA), a nonhost-specific phytotoxin produced by Alternaria alternata, was determined to be a novel natural photosynthesis inhibitor owning several action sites in chloroplasts. To further elucidate the mode of its action, studies were conducted to assess the production and involvement of reactive oxygen species (ROS) in the toxic activity of TeA. A series of experiments indicated that TeA treatment can induce chloroplast-derived ROS generation including not only (1)O(2) but also superoxide radical, H(2)O(2) and hydroxyl radicals in Eupatorium adenophorum mesophyll cells, resulting from electron leakage and charge recombination in PSII as well as thylakoid overenergization due to inhibition of the PSII electron transport beyond Q(A) and the reduction of end acceptors on the PSI acceptor side and chloroplast ATPase activity. The initial production of TeA-induced ROS was restricted to chloroplasts and accompanied with a certain degree of chloroplast damage. Subsequently, abundant ROS were quickly dispersed throughout whole cell and cellular compartments, causing a series of irreversible cellular harm such as chlorophyll breakdown, lipid peroxidation, plasma membrane rupture, chromatin condensation, DNA cleavage, and organelle disintegration, and finally resulting in rapid cell destruction and leaf necrosis. These results show that TeA causing cell necrosis of host-plants is a result of direct oxidative damage from chloroplast-mediated ROS eruption.
Collapse
Affiliation(s)
- Shiguo Chen
- Weed Research Laboratory, Nanjing Agricultural University, Nanjing 210095, China
| | | | | | | | | |
Collapse
|
42
|
Pospísil P. Production of reactive oxygen species by photosystem II. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2009; 1787:1151-60. [PMID: 19463778 DOI: 10.1016/j.bbabio.2009.05.005] [Citation(s) in RCA: 218] [Impact Index Per Article: 14.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/10/2008] [Revised: 05/05/2009] [Accepted: 05/07/2009] [Indexed: 11/29/2022]
Abstract
Photosysthetic cleavage of water molecules to molecular oxygen is a crucial process for all aerobic life on the Earth. Light-driven oxidation of water occurs in photosystem II (PSII) - a pigment-protein complex embedded in the thylakoid membrane of plants, algae and cyanobacteria. Electron transport across the thylakoid membrane terminated by NADPH and ATP formation is inadvertently coupled with the formation of reactive oxygen species (ROS). Reactive oxygen species are mainly produced by photosystem I; however, under certain circumstances, PSII contributes to the overall formation of ROS in the thylakoid membrane. Under limitation of electron transport reaction between both photosystems, photoreduction of molecular oxygen by the reducing side of PSII generates a superoxide anion radical, its dismutation to hydrogen peroxide and the subsequent formation of a hydroxyl radical terminates the overall process of ROS formation on the PSII electron acceptor side. On the PSII electron donor side, partial or complete inhibition of enzymatic activity of the water-splitting manganese complex is coupled with incomplete oxidation of water to hydrogen peroxide. The review points out the mechanistic aspects in the production of ROS on both the electron acceptor and electron donor side of PSII.
Collapse
Affiliation(s)
- Pavel Pospísil
- Laboratory of Biophysics, Department of Experimental Physics, Faculty of Science, Palacký University, Olomouc, Czech Republic.
| |
Collapse
|
43
|
Pospíšil P, Šnyrychová I, Kruk J, Strzałka K, Nauš J. Evidence that cytochrome b559 is involved in superoxide production in photosystem II: effect of synthetic short-chain plastoquinones in a cytochrome b559 tobacco mutant. Biochem J 2006; 397:321-7. [PMID: 16569212 PMCID: PMC1513276 DOI: 10.1042/bj20060068] [Citation(s) in RCA: 51] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2006] [Revised: 03/24/2006] [Accepted: 03/29/2006] [Indexed: 11/17/2022]
Abstract
Light-induced production of superoxide (O2*-) in spinach PSII (photosystem II) membrane particles was studied using EPR spin-trapping spectroscopy. The presence of exogenous PQs (plastoquinones) with a different side-chain length (PQ-n, n isoprenoid units in the side-chain) enhanced O2*- production in the following order: PQ-1>PQ-2>>PQ-9. In PSII membrane particles isolated from the tobacco cyt (cytochrome) b559 mutant which carries a single-point mutation in the beta-subunit and also has a decreased amount of the alpha-subunit, the effect of PQ-1 was less than in the wild-type. The increase in LP (low-potential) cyt b559 content, induced by the incubation of spinach PSII membrane particles at low pH, resulted in a significant increase in O2*- formation in the presence of PQ-1, whereas it had little effect on O2*- production in the absence of PQ-1. The enhancement of O2*- formation induced by PQ-1 was not abolished by DCMU [3-(3,4-dichlorophenyl)-1,1-dimethylurea]. Under anaerobic conditions, dark oxidation of LP cyt b559 increased, as pH was decreased. The presence of molecular oxygen significantly enhanced dark oxidation of LP cyt b559. Based on these findings it is suggested that short-chain PQs stimulate O2*- production via a mechanism that involves electron transfer from Pheo- (pheophytin) to LP cyt b559 and subsequent auto-oxidation of LP cyt b559.
Collapse
Key Words
- cytochrome b559 (cyt b559)
- electron paramagnetic resonance (epr)
- plastoquinone (pq)
- photosystem ii (psii)
- spin-trapping
- superoxide radical
- chl, chlorophyll
- cyt, cytochrome
- dcmu, 3-(3,4-dichlorophenyl)-1,1-dimethylurea
- desferal, deferoxamine mesylate
- empo, 2-ethoxycarbonyl-2-methyl-3,4-dihydro-2h-pyrrole-1-oxide
- hp, high-potential
- lp, low-potential
- p680, photosystem ii electron donor formed by chl a molecules
- pheo, pheophytin
- pq, plastoquinone
- pq-n, pq with n isoprenoid units in the side-chain
- psii, photosystem ii
- qa, primary quinone electron acceptor in psii
- qb, secondary quinone electron acceptor in psii
Collapse
Affiliation(s)
- Pavel Pospíšil
- *Laboratory of Biophysics, Department of Experimental Physics, Faculty of Science, Palacký University, tř. Svobody 26, 771 46 Olomouc, Czech Republic
| | - Iva Šnyrychová
- *Laboratory of Biophysics, Department of Experimental Physics, Faculty of Science, Palacký University, tř. Svobody 26, 771 46 Olomouc, Czech Republic
| | - Jerzy Kruk
- †Department of Plant Physiology and Biochemistry, Faculty of Biotechnology, Jagiellonian University, ul. Gronostajowa 7, 30-387 Krakow, Poland
| | - Kazimierz Strzałka
- †Department of Plant Physiology and Biochemistry, Faculty of Biotechnology, Jagiellonian University, ul. Gronostajowa 7, 30-387 Krakow, Poland
| | - Jan Nauš
- *Laboratory of Biophysics, Department of Experimental Physics, Faculty of Science, Palacký University, tř. Svobody 26, 771 46 Olomouc, Czech Republic
| |
Collapse
|
44
|
Hoffmann A, Hammes E, Plieth C, Desel C, Sattelmacher B, Hansen UP. Effect of CO2 supply on formation of reactive oxygen species in Arabidopsis thaliana. PROTOPLASMA 2005; 227:3-9. [PMID: 16389488 DOI: 10.1007/s00709-005-0133-3] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/18/2005] [Accepted: 05/31/2005] [Indexed: 05/06/2023]
Abstract
Light-induced generation of reactive oxygen species (ROS) in 2-week-old leaves of Arabidopsis thaliana was studied by means of the ROS-sensitive dyes nitroblue tetrazolium (NBT) and 5-(and-6)-carboxy-2',7'-dichlorodihydrofluorescein diacetate (DCF-DA). Superposition of pictures of chlorophyll fluorescence and DCF fluorescence indicated that the origin of ROS was in the chloroplasts. Experiments were done with zero, 0.1, or 10 mM NaHCO3 in the infiltration medium. Energy quenching in photosystem II was higher under low CO2 concentrations as measured by chlorophyll fluorescence. DCF fluorescence showed that CO2 deficiency led to an increase of ROS generation. In contrast, the photosystem II inhibitor 3-(3,4-dichlorophenyl)-1,1-dimethylurea reduced the light-induced increase of DCF fluorescence. This indicates that ROS production does not primarily result from over-reduction of photosystem II as caused by impeding electron flow in the electron transfer chain. More likely, it is an effect of diverting electron flux normally aimed at carboxylation in the Calvin cycle to other sinks more prone to the generation of toxic radicals. There was no significant effect of salicyl hydroxamate (a blocker of the alternative oxidase), showing that the mitochondrial electron transfer chain seems to play a minor role as already indicated by the superposition of chlorophyll and DCF fluorescence.
Collapse
Affiliation(s)
- A Hoffmann
- Center of Biochemistry and Molecular Biology, Christian-Albrechts-Universität zu Kiel, Kiel, Federal Republic of Germany
| | | | | | | | | | | |
Collapse
|
45
|
Garstka M, Nejman P, Rosiak M. The action of oxygen on chlorophyll fluorescence quenching and absorption spectra in pea thylakoid membranes under the steady-state conditions. JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY. B, BIOLOGY 2004; 77:79-92. [PMID: 15542365 DOI: 10.1016/j.jphotobiol.2004.09.001] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/19/2003] [Revised: 08/21/2004] [Accepted: 08/24/2004] [Indexed: 11/23/2022]
Abstract
The effect of oxygen concentration on both absorption and chlorophyll fluorescence spectra was investigated in isolated pea thylakoids at weak actinic light under the steady-state conditions. Upon the rise of oxygen concentration from anaerobiosis up to 412 microM a gradual absorbance increase around both 437 and 670 nm was observed, suggesting the disaggregation of LHCII and destacking of thylakoids. Simultaneously, an increase in oxygen concentration resulted in a decline in the Chl fluorescence at 680 nm to about 60% of the initial value. The plot of normalized Chl fluorescence quenching, F(-O(2))/F(+O(2)), showed discontinuity above 275 microM O(2), revealing two phases of quenching, at both lower and higher oxygen concentrations. The inhibition of photosystem II by DCMU or atrazine as well as that of cyt b(6)f by myxothiazol attenuated the oxygen-induced quenching events observed above 275 microM O(2), but did not modify the first phase of oxygen action. These data imply that the oxygen mediated Chl fluorescence quenching is partially independent on non-cyclic electron flow. The second phase of oxygen-induced decline in Chl fluorescence is diminished in thylakoids with poisoned PSII and cyt b(6)f activities and treated with rotenone or N-ethylmaleimide to inhibit NAD(P)H-plastoquinone dehydrogenase. The data suggest that under weak light and high oxygen concentration the Chl fluorescence quenching results from interactions between oxygen and PSI, cyt b(6)f and Ndh. On the contrary, inhibition of non-cyclic electron flow by antimycin A or uncoupling of thylakoids by carbonyl cyanide m-chlorophenyl hydrazone did not modify the steady-state oxygen effect on Chl fluorescence quenching. The addition of NADH protected thylakoids against oxygen-induced Chl fluorescence quenching, whereas in the presence of exogenic duroquinone the decrease in Chl fluorescence to one half of the initial level did not result from the oxygen effect, probably due to oxygen action as a weak electron acceptor from PQ pool and an insufficient non-photochemical quencher. The data indicate that mechanism of oxygen-induced Chl fluorescence quenching depends significantly on oxygen concentration and is related to both structural rearrangement of thylakoids and the direct oxygen reduction by photosynthetic complexes.
Collapse
Affiliation(s)
- Maciej Garstka
- Department of Metabolic Regulation, Institute of Biochemistry, Faculty of Biology, Warsaw University, Miecznikowa 1, PL-02-096 Warszawa, Poland.
| | | | | |
Collapse
|
46
|
Semin BK, Seibert M. Iron bound to the high-affinity Mn-binding site of the oxygen-evolving complex shifts the pK of a component controlling electron transport via Y(Z). Biochemistry 2004; 43:6772-82. [PMID: 15157111 DOI: 10.1021/bi036047p] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Flash-probe fluorescence spectroscopy was used to compare the pH dependence of charge recombination between Y(Z)(*) and Q(a)(-) in Mn-depleted, photosystem II membranes [PSII(-Mn)] and in membranes with the high-affinity (HA(Z)) Mn-binding site blocked by iron [PSII(-Mn,+Fe); Semin, B. K., Ghirardi, M. L., and Seibert, M. (2002) Biochemistry 41, 5854-5864]. The apparent half-time for fluorescence decay (t(1/2)) in PSII(-Mn) increased from 9 ms at pH 4.4 to 75 ms at pH 9.0 [with an apparent pK (pK(app)) of 7.1]. The actual fluorescence decay kinetics can be fit to one exponential component at pH <6.0 (t(1/2) = 9.5 ms), but it requires an additional component at pH >6.0 (t(1/2) = 385 ms). Similar measurements with PSII(-Mn,+Fe) membranes show that iron binding has little effect on the maximum and minimum t(1/2) values measured at alkaline and acidic pHs but that it does shift the pK(app) from 7.1 to 6.1 toward the more acidic pK(app) value typical of intact membranes. Light-induced Fe(II) blocking of the PSII(-Mn) membrane is accompanied by a decrease in buffer Fe(II) concentration. This decrease was not the result of Fe(II) binding, but rather of its oxidation at two sites, the HA(Z) site and the low-affinity site. Mössbauer spectroscopy at 80 K on PSII(-Mn,+Fe) samples, prepared under conditions providing the maximal blocking effect but minimizing the amount of nonspecifically bound iron cations, supports this conclusion since this method detected only Fe(III) cations bound to the membranes. Correlation of the kinetics of Fe(II) oxidation with the blocking parameters showed that blocking occurs after four to five Fe(II) cations were oxidized at the HA(Z) site. In summary, the blocking of the HA(Z) Mn-binding site by iron in PSII(-Mn) membranes not only prevents the access of exogenous donors to Y(Z) but also partially restores the properties of the hydrogen bond net found in intact PS(II), which in turn controls the rate of electron transport to Y(Z).
Collapse
Affiliation(s)
- Boris K Semin
- Basic Sciences Center, National Renewable Energy Laboratory, Golden, Colorado 80401, USA
| | | |
Collapse
|
47
|
Pospísil P, Arató A, Krieger-Liszkay A, Rutherford AW. Hydroxyl Radical Generation by Photosystem II. Biochemistry 2004; 43:6783-92. [PMID: 15157112 DOI: 10.1021/bi036219i] [Citation(s) in RCA: 102] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The photogeneration of hydroxyl radicals (OH(*)) in photosystem II (PSII) membranes was studied using EPR spin-trapping spectroscopy. Two kinetically distinguishable phases in the formation of the spin trap-hydroxyl (POBN-OH) adduct EPR signal were observed: the first phase (t(1/2) = 7.5 min) and the second phase (t(1/2) = 30 min). The generation of OH(*) was found to be suppressed in the absence of the Mn-complex, but it was restored after readdition of an artificial electron donor (DPC). Hydroxyl radical generation was also lost in the absence of oxygen, whereas it was stimulated when the oxygen concentration was increased. The production of OH(*) during the first kinetic phase was sensitive to the presence of SOD, whereas catalase and EDTA diminished the production of OH(*) during the second kinetic phase. The POBN-OH adduct EPR signal during the first phase exhibits a similar pH-dependence as the ability to oxidize the non-heme iron, as monitored by the Fe(3+) (g = 8) EPR signal: both EPR signals gradually decreased as the pH value was lowered below pH 6.5 and were absent at pH 5. Sodium formate decreases the production of OH(*) in intact and Mn-deleted PSII membranes. Upon illumination of PSII membranes, both superoxide, as measured by EPR signal from the spin trap-superoxide (EMPO-OOH) adduct, and H(2)O(2), measured colormetrically, were generated. These results indicated that OH(*) is produced on the electron acceptor side of PSII by two different routes, (1) O(2)(*)(-), which is generated by oxygen reduction on the acceptor side of PSII, interacts with a PSII metal center, probably the non-heme iron, to form an iron-peroxide species that is further reduced to OH(*) by an electron from PSII, presumably via Q(A)(-), and (2) O(2)(*)(-) dismutates to form free H(2)O(2) that is then reduced to OH(*) via the Fenton reaction in the presence of metal ions, the most likely being Mn(2+) and Fe(2+) released from photodamaged PSII. The two different routes of OH(*) generation are discussed in the context of photoinhibition.
Collapse
Affiliation(s)
- Pavel Pospísil
- Service Bioénérgetique, Département de Biologie Joliot Curie, CEA Saclay, F-91191 Gif-sur-Yvette, France.
| | | | | | | |
Collapse
|
48
|
Johnson GN. Thiol regulation of the thylakoid electron transport chain--a missing link in the regulation of photosynthesis? Biochemistry 2003; 42:3040-4. [PMID: 12627970 DOI: 10.1021/bi027011k] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Avoidance of over-reduction of the chloroplast ferredoxin pool is of paramount importance for plants in avoiding oxidative stress. The redox state of this pool can be controlled through regulation of the thylakoid electron transport chain. A model is presented for regulation of this chain via a thiol reduction mechanism, possibly involving a thioredoxin. It is shown in isolated thylakoids that electron transport is inhibited by the thiol reducing agent dithiothreitol. The kinetics of this reduction are rapid and readily reversible. The midpoint redox potential is -365 mV at pH 7.7, with a pH dependency of about -90 mV/pH. At physiological pH values, this places the potential of the species titrated between that of ferredoxin and NADPH and thus in the right potential range to be regulating the redox poise of the ferredoxin pool. This is also close to the potential of NADPH-malate dehydrogenase, an enzyme known to be regulated by thioredoxin. Regulation of electron transport by thioredoxin provides a mechanistic link between the regulation of photosynthesis and gene expression by sugars and the redox regulation of gene expression mediated through the plastoquinone pool.
Collapse
Affiliation(s)
- Giles N Johnson
- School of Biological Sciences, University of Manchester, 3.614 Stopford Building, Oxford Road, Manchester, England M13 9PT.
| |
Collapse
|
49
|
Ivanov B, Khorobrykh S. Participation of photosynthetic electron transport in production and scavenging of reactive oxygen species. Antioxid Redox Signal 2003; 5:43-53. [PMID: 12626116 DOI: 10.1089/152308603321223531] [Citation(s) in RCA: 59] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
The photosynthetic electron transport chain (PETC) is the principal place of appearance of reactive oxygen species (ROS) in plants under illumination. The peculiarities of this process in different segments of the PETC are discussed. Oxygen uptake observed under impaired electron donation to photosystem II is attributed mainly to hydroperoxide formation by reaction of oxygen with organic radicals generated after detachment of electrons by P680(+). Oxygen reduction in the plastoquinone pool is suggested to start with the reaction of O(2) with plastosemiquinone, and to be followed by reduction of superoxide to hydrogen peroxide by plastohydroquinone. The distribution of plastoquinone throughout the thylakoid membrane interior provides for the generation of ROS by this route all along the membrane surface. O(2) reduction at the acceptor side of photosystem I remains poorly understood. The regeneration of antioxidants is stated to be a priority task of photosynthetic electron transport in view of the effectiveness of monodehydroascorbate as electron acceptor. We propose that ROS generation in the plastoquinone pool and the possible formation of hydroperoxides in the vicinity of photosystem II are key processes participating in the primary stages of redox signaling.
Collapse
Affiliation(s)
- Boris Ivanov
- Institute of Basic Biological Problems, Russian Academy of Sciences, Pushchino, Moscow region, 142290 Russia.
| | | |
Collapse
|
50
|
Effect of Mn cluster on the formation of Superoxide radicals in photoinhibition of photosystem II. CHINESE SCIENCE BULLETIN-CHINESE 2001. [DOI: 10.1007/bf02901162] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
|