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Degen GE, Jackson PJ, Proctor MS, Zoulias N, Casson SA, Johnson MP. High cyclic electron transfer via the PGR5 pathway in the absence of photosynthetic control. PLANT PHYSIOLOGY 2023; 192:370-386. [PMID: 36774530 PMCID: PMC10152662 DOI: 10.1093/plphys/kiad084] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/25/2022] [Accepted: 01/24/2023] [Indexed: 05/03/2023]
Abstract
The light reactions of photosynthesis couple electron and proton transfers across the thylakoid membrane, generating NADPH, and proton motive force (pmf) that powers the endergonic synthesis of ATP by ATP synthase. ATP and NADPH are required for CO2 fixation into carbohydrates by the Calvin-Benson-Bassham cycle. The dominant ΔpH component of the pmf also plays a photoprotective role in regulating photosystem II light harvesting efficiency through nonphotochemical quenching (NPQ) and photosynthetic control via electron transfer from cytochrome b6f (cytb6f) to photosystem I. ΔpH can be adjusted by increasing the proton influx into the thylakoid lumen via upregulation of cyclic electron transfer (CET) or decreasing proton efflux via downregulation of ATP synthase conductivity (gH+). The interplay and relative contributions of these two elements of ΔpH control to photoprotection are not well understood. Here, we showed that an Arabidopsis (Arabidopsis thaliana) ATP synthase mutant hunger for oxygen in photosynthetic transfer reaction 2 (hope2) with 40% higher proton efflux has supercharged CET. Double crosses of hope2 with the CET-deficient proton gradient regulation 5 and ndh-like photosynthetic complex I lines revealed that PROTON GRADIENT REGULATION 5 (PGR5)-dependent CET is the major pathway contributing to higher proton influx. PGR5-dependent CET allowed hope2 to maintain wild-type levels of ΔpH, CO2 fixation and NPQ, however photosynthetic control remained absent and PSI was prone to photoinhibition. Therefore, high CET in the absence of ATP synthase regulation is insufficient for PSI photoprotection.
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Affiliation(s)
- Gustaf E Degen
- Plants, Photosynthesis and Soil, School of Biosciences, University of Sheffield, Firth Court, Western Bank, Sheffield S10 2TN, UK
| | - Philip J Jackson
- Plants, Photosynthesis and Soil, School of Biosciences, University of Sheffield, Firth Court, Western Bank, Sheffield S10 2TN, UK
- Department of Chemical and Biological Engineering, University of Sheffield, Sheffield S1 4NL, UK
| | - Matthew S Proctor
- Plants, Photosynthesis and Soil, School of Biosciences, University of Sheffield, Firth Court, Western Bank, Sheffield S10 2TN, UK
| | - Nicholas Zoulias
- Plants, Photosynthesis and Soil, School of Biosciences, University of Sheffield, Firth Court, Western Bank, Sheffield S10 2TN, UK
| | - Stuart A Casson
- Plants, Photosynthesis and Soil, School of Biosciences, University of Sheffield, Firth Court, Western Bank, Sheffield S10 2TN, UK
| | - Matthew P Johnson
- Plants, Photosynthesis and Soil, School of Biosciences, University of Sheffield, Firth Court, Western Bank, Sheffield S10 2TN, UK
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2
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Cryo-EM structures of the Synechocystis sp. PCC 6803 cytochrome b6f complex with and without the regulatory PetP subunit. Biochem J 2022; 479:1487-1503. [PMID: 35726684 PMCID: PMC9342900 DOI: 10.1042/bcj20220124] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2022] [Revised: 06/01/2022] [Accepted: 06/21/2022] [Indexed: 11/17/2022]
Abstract
In oxygenic photosynthesis, the cytochrome b6f (cytb6f) complex links the linear electron transfer (LET) reactions occurring at photosystems I and II and generates a transmembrane proton gradient via the Q-cycle. In addition to this central role in LET, cytb6f also participates in a range of processes including cyclic electron transfer (CET), state transitions and photosynthetic control. Many of the regulatory roles of cytb6f are facilitated by auxiliary proteins that differ depending upon the species, yet because of their weak and transient nature the structural details of these interactions remain unknown. An apparent key player in the regulatory balance between LET and CET in cyanobacteria is PetP, a ∼10 kDa protein that is also found in red algae but not in green algae and plants. Here, we used cryogenic electron microscopy to determine the structure of the Synechocystis sp. PCC 6803 cytb6f complex in the presence and absence of PetP. Our structures show that PetP interacts with the cytoplasmic side of cytb6f, displacing the C-terminus of the PetG subunit and shielding the C-terminus of cytochrome b6, which binds the heme cn cofactor that is suggested to mediate CET. The structures also highlight key differences in the mode of plastoquinone binding between cyanobacterial and plant cytb6f complexes, which we suggest may reflect the unique combination of photosynthetic and respiratory electron transfer in cyanobacterial thylakoid membranes. The structure of cytb6f from a model cyanobacterial species amenable to genetic engineering will enhance future site-directed mutagenesis studies of structure-function relationships in this crucial ET complex.
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Kramer M, Rodriguez-Heredia M, Saccon F, Mosebach L, Twachtmann M, Krieger-Liszkay A, Duffy C, Knell RJ, Finazzi G, Hanke GT. Regulation of photosynthetic electron flow on dark to light transition by ferredoxin:NADP(H) oxidoreductase interactions. eLife 2021; 10:56088. [PMID: 33685582 PMCID: PMC7984839 DOI: 10.7554/elife.56088] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2020] [Accepted: 02/25/2021] [Indexed: 01/12/2023] Open
Abstract
During photosynthesis, electron transport is necessary for carbon assimilation and must be regulated to minimize free radical damage. There is a longstanding controversy over the role of a critical enzyme in this process (ferredoxin:NADP(H) oxidoreductase, or FNR), and in particular its location within chloroplasts. Here we use immunogold labelling to prove that FNR previously assigned as soluble is in fact membrane associated. We combined this technique with a genetic approach in the model plant Arabidopsis to show that the distribution of this enzyme between different membrane regions depends on its interaction with specific tether proteins. We further demonstrate a correlation between the interaction of FNR with different proteins and the activity of alternative photosynthetic electron transport pathways. This supports a role for FNR location in regulating photosynthetic electron flow during the transition from dark to light.
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Affiliation(s)
- Manuela Kramer
- School of Biochemistry and Chemistry, Queen Mary University of London, London, United Kingdom.,Department of Plant Physiology, Faculty of Biology and Chemistry, University of Osnabrück, Osnabrück, Germany
| | | | - Francesco Saccon
- School of Biochemistry and Chemistry, Queen Mary University of London, London, United Kingdom
| | - Laura Mosebach
- Institute of Plant Biology and Biotechnology, University of Münster, Münster, Germany
| | - Manuel Twachtmann
- Department of Plant Physiology, Faculty of Biology and Chemistry, University of Osnabrück, Osnabrück, Germany
| | - Anja Krieger-Liszkay
- Institute for Integrative Biology of the Cell (I2BC), CEA, CNRS, Univ Paris-Sud, Université Paris-Saclay, Paris, France
| | - Chris Duffy
- School of Biochemistry and Chemistry, Queen Mary University of London, London, United Kingdom
| | - Robert J Knell
- School of Biochemistry and Chemistry, Queen Mary University of London, London, United Kingdom
| | - Giovanni Finazzi
- Laboratoire de Physiologie Cellulaire et Végétale, UMR 5168, Centre National de la Recherche Scientifique (CNRS), Commissariat a` l'Energie Atomique et aux Energies Alternatives (CEA), Université Grenoble Alpes, Institut National Recherche Agronomique (INRA), Institut de Recherche en Sciences et Technologies pour le Vivant (iRTSV), CEA Grenoble, Grenoble, France
| | - Guy Thomas Hanke
- School of Biochemistry and Chemistry, Queen Mary University of London, London, United Kingdom.,Department of Plant Physiology, Faculty of Biology and Chemistry, University of Osnabrück, Osnabrück, Germany
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4
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Sarewicz M, Pintscher S, Pietras R, Borek A, Bujnowicz Ł, Hanke G, Cramer WA, Finazzi G, Osyczka A. Catalytic Reactions and Energy Conservation in the Cytochrome bc1 and b6f Complexes of Energy-Transducing Membranes. Chem Rev 2021; 121:2020-2108. [PMID: 33464892 PMCID: PMC7908018 DOI: 10.1021/acs.chemrev.0c00712] [Citation(s) in RCA: 61] [Impact Index Per Article: 20.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2020] [Indexed: 12/16/2022]
Abstract
This review focuses on key components of respiratory and photosynthetic energy-transduction systems: the cytochrome bc1 and b6f (Cytbc1/b6f) membranous multisubunit homodimeric complexes. These remarkable molecular machines catalyze electron transfer from membranous quinones to water-soluble electron carriers (such as cytochromes c or plastocyanin), coupling electron flow to proton translocation across the energy-transducing membrane and contributing to the generation of a transmembrane electrochemical potential gradient, which powers cellular metabolism in the majority of living organisms. Cytsbc1/b6f share many similarities but also have significant differences. While decades of research have provided extensive knowledge on these enzymes, several important aspects of their molecular mechanisms remain to be elucidated. We summarize a broad range of structural, mechanistic, and physiological aspects required for function of Cytbc1/b6f, combining textbook fundamentals with new intriguing concepts that have emerged from more recent studies. The discussion covers but is not limited to (i) mechanisms of energy-conserving bifurcation of electron pathway and energy-wasting superoxide generation at the quinol oxidation site, (ii) the mechanism by which semiquinone is stabilized at the quinone reduction site, (iii) interactions with substrates and specific inhibitors, (iv) intermonomer electron transfer and the role of a dimeric complex, and (v) higher levels of organization and regulation that involve Cytsbc1/b6f. In addressing these topics, we point out existing uncertainties and controversies, which, as suggested, will drive further research in this field.
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Affiliation(s)
- Marcin Sarewicz
- Department
of Molecular Biophysics, Faculty of Biochemistry, Biophysics and Biotechnology, Jagiellonian University, 30-387 Kraków, Poland
| | - Sebastian Pintscher
- Department
of Molecular Biophysics, Faculty of Biochemistry, Biophysics and Biotechnology, Jagiellonian University, 30-387 Kraków, Poland
| | - Rafał Pietras
- Department
of Molecular Biophysics, Faculty of Biochemistry, Biophysics and Biotechnology, Jagiellonian University, 30-387 Kraków, Poland
| | - Arkadiusz Borek
- Department
of Molecular Biophysics, Faculty of Biochemistry, Biophysics and Biotechnology, Jagiellonian University, 30-387 Kraków, Poland
| | - Łukasz Bujnowicz
- Department
of Molecular Biophysics, Faculty of Biochemistry, Biophysics and Biotechnology, Jagiellonian University, 30-387 Kraków, Poland
| | - Guy Hanke
- School
of Biological and Chemical Sciences, Queen
Mary University of London, London E1 4NS, U.K.
| | - William A. Cramer
- Department
of Biological Sciences, Purdue University, West Lafayette, Indiana 47907 United States
| | - Giovanni Finazzi
- Laboratoire
de Physiologie Cellulaire et Végétale, Université Grenoble Alpes, Centre National Recherche Scientifique,
Commissariat Energie Atomique et Energies Alternatives, Institut National
Recherche l’agriculture, l’alimentation et l’environnement, 38054 Grenoble Cedex 9, France
| | - Artur Osyczka
- Department
of Molecular Biophysics, Faculty of Biochemistry, Biophysics and Biotechnology, Jagiellonian University, 30-387 Kraków, Poland
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5
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Malone LA, Proctor MS, Hitchcock A, Hunter CN, Johnson MP. Cytochrome b 6f - Orchestrator of photosynthetic electron transfer. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2021; 1862:148380. [PMID: 33460588 DOI: 10.1016/j.bbabio.2021.148380] [Citation(s) in RCA: 51] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Subscribe] [Scholar Register] [Received: 10/08/2020] [Revised: 01/06/2021] [Accepted: 01/09/2021] [Indexed: 11/18/2022]
Abstract
Cytochrome b6f (cytb6f) lies at the heart of the light-dependent reactions of oxygenic photosynthesis, where it serves as a link between photosystem II (PSII) and photosystem I (PSI) through the oxidation and reduction of the electron carriers plastoquinol (PQH2) and plastocyanin (Pc). A mechanism of electron bifurcation, known as the Q-cycle, couples electron transfer to the generation of a transmembrane proton gradient for ATP synthesis. Cytb6f catalyses the rate-limiting step in linear electron transfer (LET), is pivotal for cyclic electron transfer (CET) and plays a key role as a redox-sensing hub involved in the regulation of light-harvesting, electron transfer and photosynthetic gene expression. Together, these characteristics make cytb6f a judicious target for genetic manipulation to enhance photosynthetic yield, a strategy which already shows promise. In this review we will outline the structure and function of cytb6f with a particular focus on new insights provided by the recent high-resolution map of the complex from Spinach.
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Affiliation(s)
- Lorna A Malone
- Department of Molecular Biology and Biotechnology, University of Sheffield, Sheffield S10 2TN, UK
| | - Matthew S Proctor
- Department of Molecular Biology and Biotechnology, University of Sheffield, Sheffield S10 2TN, UK
| | - Andrew Hitchcock
- Department of Molecular Biology and Biotechnology, University of Sheffield, Sheffield S10 2TN, UK
| | - C Neil Hunter
- Department of Molecular Biology and Biotechnology, University of Sheffield, Sheffield S10 2TN, UK
| | - Matthew P Johnson
- Department of Molecular Biology and Biotechnology, University of Sheffield, Sheffield S10 2TN, UK.
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6
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Ferredoxin-mediated reduction of 2-nitrothiophene inhibits photosynthesis: mechanism and herbicidal potential. Biochem J 2020; 477:1149-1158. [PMID: 32150261 DOI: 10.1042/bcj20190830] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2019] [Revised: 02/19/2020] [Accepted: 03/09/2020] [Indexed: 01/13/2023]
Abstract
Searching for compounds that inhibit the growth of photosynthetic organisms highlighted a prominent effect at micromolar concentrations of the nitroheteroaromatic thioether, 2-nitrothiophene, applied in the light. Since similar effects were reminiscent to those obtained also by radicals produced under excessive illumination or by herbicides, and in light of its redox potential, we suspected that 2-nitrothiophene was reduced by ferredoxin, a major reducing compound in the light. In silico examination using docking and tunneling computing algorithms of the putative interaction between 2-nitrothiophene and cyanobacterial ferredoxin has suggested a site of interaction enabling robust electron transfer from the iron-sulfur cluster of ferredoxin to the nitro group of 2-nitrothiophene. ESR and oximetry analyses of cyanobacterial cells (Anabaena PCC7120) treated with 50 μM 2-nitrothiophene under illumination revealed accumulation of oxygen radicals and peroxides. Gas chromatography mass spectrometry analysis of 2-nitrothiophene-treated cells identified cytotoxic nitroso and non-toxic amino derivatives. These products of the degradation pathway of 2-nitrohiophene, which initializes with a single electron transfer that forms a short-live anion radical, are then decomposed to nitrate and thiophene, and may be further reduced to a nitroso hydroxylamine and amino derivatives. This mechanism of toxicity is similar to that of nitroimidazoles (e.g. ornidazole and metronidazole) reduced by ferredoxin in anaerobic bacteria and protozoa, but differs from that of ornidazole in planta.
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7
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Mulo P, Medina M. Interaction and electron transfer between ferredoxin-NADP + oxidoreductase and its partners: structural, functional, and physiological implications. PHOTOSYNTHESIS RESEARCH 2017; 134:265-280. [PMID: 28361449 DOI: 10.1007/s11120-017-0372-0] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/27/2016] [Accepted: 03/20/2017] [Indexed: 05/25/2023]
Abstract
Ferredoxin-NADP+ reductase (FNR) catalyzes the last step of linear electron transfer in photosynthetic light reactions. The FAD cofactor of FNR accepts two electrons from two independent reduced ferredoxin molecules (Fd) in two sequential steps, first producing neutral semiquinone and then the fully anionic reduced, or hydroquinone, form of the enzyme (FNRhq). FNRhq transfers then both electrons in a single hydride transfer step to NADP+. We are presenting the recent progress in studies focusing on Fd:FNR interaction and subsequent electron transfer processes as well as on interaction of FNR with NADP+/H followed by hydride transfer, both from the structural and functional point of views. We also present the current knowledge about the physiological role(s) of various FNR isoforms present in the chloroplasts of higher plants and the functional impact of subchloroplastic location of FNR. Moreover, open questions and current challenges about the structure, function, and physiology of FNR are discussed.
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Affiliation(s)
- Paula Mulo
- Molecular Plant Biology, University of Turku, 20520, Turku, Finland
| | - Milagros Medina
- Department of Biochemistry and Molecular and Cellular Biology, Faculty of Sciences, and Institute of Biocomputation and Physics of Complex Systems (Joint Units: BIFI-IQFR and GBsC-CSIC), University of Zaragoza, 50009, Zaragoza, Spain.
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8
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Guo L, Wang P, Gu Z, Jin X, Yang R. Proteomic analysis of broccoli sprouts by iTRAQ in response to jasmonic acid. JOURNAL OF PLANT PHYSIOLOGY 2017; 218:16-25. [PMID: 28763705 DOI: 10.1016/j.jplph.2017.07.003] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/26/2016] [Revised: 07/05/2017] [Accepted: 07/05/2017] [Indexed: 05/02/2023]
Abstract
Jasmonic acid (JA) is well known as a linolenic acid-derived signal molecule related to the plant response to biotic and abiotic stresses. JA can regulate various plant metabolisms, such as glucosinolate metabolism. In this study, the proteome profiles of broccoli sprouts under JA treatment were analyzed using the iTRAQ-based quantitative proteome approach. A total of 122 differentially expressed proteins participating in a wide range of physiological processes were confidently identified in broccoli sprouts treated with JA. Functional classification analysis showed that photosynthesis and protein synthesis were inhibited by JA treatment, thereby inhibiting sprout growth, while proteins related to carbohydrate catabolism and amino acid metabolism showed an increased expression. Additionally, proteins involved in defense and secondary metabolism were also up-regulated. Proteins related to glucosinolate biosynthesis and degradation were mediated by JA, leading to the accumulation of glucosinolates and sulforaphane. These results indicate that JA stimulated a defense response at the proteome level by redirecting metabolism of growth and physiology in broccoli sprouts.
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Affiliation(s)
- Liping Guo
- College of Food Science and Technology, Nanjing Agricultural University, Nanjing, 210095, People's Republic of China; College of Food Science and Engineering, Qingdao Agricultural University, Qingdao, 266109, People's Republic of China
| | - Pei Wang
- College of Food Science and Technology, Nanjing Agricultural University, Nanjing, 210095, People's Republic of China
| | - Zhenxin Gu
- College of Food Science and Technology, Nanjing Agricultural University, Nanjing, 210095, People's Republic of China
| | - Xiaolin Jin
- College of Food Science and Technology, Nanjing Agricultural University, Nanjing, 210095, People's Republic of China
| | - Runqiang Yang
- College of Food Science and Technology, Nanjing Agricultural University, Nanjing, 210095, People's Republic of China.
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9
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Grzyb J, Gieczewska K, Łabuz J, Sztatelman O. Detailed characterization of Synechocystis PCC 6803 ferredoxin:NADP + oxidoreductase interaction with model membranes. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2017; 1860:281-291. [PMID: 29038021 DOI: 10.1016/j.bbamem.2017.10.012] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 03/10/2017] [Revised: 10/08/2017] [Accepted: 10/10/2017] [Indexed: 11/15/2022]
Abstract
Direct interaction of ferredoxin:NADP+ oxidoreductase (FNR) with thylakoid membranes was postulated as a part of the cyclic electron flow mechanism. In vitro binding of FNR to digalactosyldiacylglycerol and monogalactosyldiacylglycerol membranes was also shown. In this paper we deal with the latter interaction in more detail describing the effect for two FNR forms of Synechocystis PCC 6803. The so-called short FNR (sFNR) is homologous to FNR from higher plant chloroplasts. The long FNR (lFNR) form contains an additional domain, responsible for the interaction with phycobilisomes. We compare the binding of both sFNR and lFNR forms to native and non-native lipids. We also include factors which could modulate this process: pH change, temperature change, presence of ferredoxin, NADP+ and NADPH and heavy metals. For the lFNR, we also include phycobilisomes as a modulating factor. The membrane binding is generally faster at lower pH. The sFNR was binding faster than lFNR. Ferredoxin isoforms with higher midpoint potential, as well as NADPH and NADP+, weakened the binding. Charged lipids and high phosphate promoted the binding. Heavy metal ions decreased the rate of membrane binding only when FNR was preincubated with them before injection beneath the monolayer. FNR binding was limited to surface lipid groups and did not influence hydrophobic chain packing. Taken together, FNR interaction with lipids appears to be non-specific, with an electrostatic component. This suggests that the direct FNR interaction with lipids is most likely not a factor in directing electron transfer, but should be taken into account during in vitro studies.
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Affiliation(s)
- Joanna Grzyb
- Department of Biophysics, Faculty of Biotechnology, University of Wroclaw, F. Joliot Curie 14a, PL-50383 Wroclaw, Poland; Laboratory of Biological Physics, Institute of Physics Polish Academy of Sciences, Aleja Lotników 32/46, PL-02668 Warsaw, Poland.
| | - Katarzyna Gieczewska
- Department of Plant Anatomy and Cytology, Faculty of Biology, University of Warsaw, Miecznikowa 1, PL-02096 Warsaw, Poland; Department of Biophysics, Institute of Physics, Maria Sklodowska-Curie University, M. Sklodowska-Curie sq. 5, PL-20031 Lublin, Poland
| | - Justyna Łabuz
- Laboratory of Photobiology, Malopolska Centre of Biotechnology, Jagiellonian University, Gronostajowa 7A, PL-30387 Krakow, Poland
| | - Olga Sztatelman
- Department of Plant Biochemistry, Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Pawińskiego 5a, PL-02106 Warszawa, Poland
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10
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Goss T, Hanke G. The end of the line: can ferredoxin and ferredoxin NADP(H) oxidoreductase determine the fate of photosynthetic electrons? Curr Protein Pept Sci 2014; 15:385-93. [PMID: 24678667 PMCID: PMC4030315 DOI: 10.2174/1389203715666140327113733] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2013] [Revised: 11/22/2013] [Accepted: 03/16/2014] [Indexed: 12/30/2022]
Abstract
At the end of the linear photosynthetic electron transfer (PET) chain, the small soluble protein ferredoxin (Fd) transfers electrons to Fd:NADP(H) oxidoreductase (FNR), which can then reduce NADP+ to support C assimilation. In addition to this linear electron flow (LEF), Fd is also thought to mediate electron flow back to the membrane complexes by different cyclic electron flow (CEF) pathways: either antimycin A sensitive, NAD(P)H complex dependent, or through FNR located at the cytochrome b6f complex. Both Fd and FNR are present in higher plant genomes as multiple gene copies, and it is now known that specific Fd iso-proteins can promote CEF. In addition, FNR iso-proteins vary in their ability to dynamically interact with thylakoid membrane complexes, and it has been suggested that this may also play a role in CEF. We will highlight work on the different Fd-isoproteins and FNR-membrane association found in the bundle sheath (BSC) and mesophyll (MC) cell chloroplasts of the C4 plant maize. These two cell types perform predominantly CEF and LEF, and the properties and activities of Fd and FNR in the BSC and MC are therefore specialized for CEF and LEF respectively. A diversity of Fd isoproteins and dynamic FNR location has also been recorded in C3 plants, algae and cyanobacteria. This indicates that the principles learned from the extreme electron transport situations in the BSC and MC of maize might be usefully applied to understanding the dynamic transition between these states in other systems.
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Affiliation(s)
| | - Guy Hanke
- Department of Plant Physiology, Faculty of Biology and Chemistry, University of Osnabrück,11 Barbara Strasse, Osnabrueck, DE-49076, Germany.
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11
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Chloroplast-targeted ferredoxin-NADP(+) oxidoreductase (FNR): structure, function and location. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2010; 1807:927-34. [PMID: 20934402 DOI: 10.1016/j.bbabio.2010.10.001] [Citation(s) in RCA: 64] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/16/2010] [Revised: 10/01/2010] [Accepted: 10/02/2010] [Indexed: 11/20/2022]
Abstract
Ferredoxin-NADP(+) oxidoreductase (FNR) is a ubiquitous flavin adenine dinucleotide (FAD)-binding enzyme encoded by a small nuclear gene family in higher plants. The chloroplast targeted FNR isoforms are known to be responsible for the final step of linear electron flow transferring electrons from ferredoxin to NADP(+), while the putative role of FNR in cyclic electron transfer has been under discussion for decades. FNR has been found from three distinct chloroplast compartments (i) at the thylakoid membrane, (ii) in the soluble stroma, and (iii) at chloroplast inner envelope. Recent in vivo studies have indicated that besides the membrane-bound FNR, also the soluble FNR is photosynthetically active. Two chloroplast proteins, Tic62 and TROL, were recently identified and shown to form high molecular weight protein complexes with FNR at the thylakoid membrane, and thus seem to act as the long-sought molecular anchors of FNR to the thylakoid membrane. Tic62-FNR complexes are not directly involved in photosynthetic reactions, but Tic62 protects FNR from inactivation during the dark periods. TROL-FNR complexes, however, have an impact on the photosynthetic performance of the plants. This article is part of a Special Issue entitled: Regulation of Electron Transport in Chloroplasts.
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12
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Abstract
Evidence is given for the existence of an electron transport pathway to oxygen in the thylakoid membranes of chloroplasts (chlororespiration). Plastoquinone is shown to be a redox carrier common to both photosynthetic and chlororespiratory pathways. It is shown that, in dark-adapted chloroplasts, an electrochemical gradient is built up across the thylakoid membrane by transfer of electrons through the chlororespiratory chain as well as by reverse functioning of the chloroplast ATPases. It is proposed that these mechanisms ensure recycling of the ATP and NAD(P)H generated by the glycolytic pathway converting starch into triose phosphates. Chlororespiration is thus an O(2)-uptake process distinct from photorespiration and the Mehler reaction. The evolutionary significance of chlororespiration is discussed.
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Affiliation(s)
- P Bennoun
- Institut de Biologie Physico-Chimique, 13, rue Pierre et Marie Curie, 75005, Paris, France
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13
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Grzyb J, Gagoś M, Gruszecki WI, Bojko M, Strzałka K. Interaction of ferredoxin:NADP+ oxidoreductase with model membranes. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2008; 1778:133-42. [DOI: 10.1016/j.bbamem.2007.09.028] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/28/2007] [Revised: 08/17/2007] [Accepted: 09/17/2007] [Indexed: 10/22/2022]
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14
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Bojko M, Kruk J, Wieckowski S. Plastoquinones are effectively reduced by ferredoxin:NADP+ oxidoreductase in the presence of sodium cholate micelles. Significance for cyclic electron transport and chlororespiration. PHYTOCHEMISTRY 2003; 64:1055-1060. [PMID: 14568071 DOI: 10.1016/s0031-9422(03)00506-5] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
The effect of sodium cholate and other detergents (Triton X-100, sodium dodecyl sulphate, octyl glucoside, myristyltrimethylammonium bromide) on the reduction of plastoquinones (PQ) with a different length of the side-chain by spinach ferredoxin:NADP(+) oxidoreductase (FNR) in the presence of NADPH has been studied. Both NADPH oxidation and oxygen uptake due to plastosemiquinone autoxidation were highly stimulated only in the presence of sodium cholate among the used detergents. Sodium cholate at the concentration of 20 mM was found to be the most effective on both PQ-4 and PQ-9-mediated oxygen uptake. The FNR-dependent reduction of plastoquinones incorporated into sodium cholate micelles was stimulated by spinach ferredoxin but inhibited by Mg(2+) ions. It was concluded that the structure of sodium cholate micelles facilitates contact of plastoquinone molecules with the enzyme and creates favourable conditions for the reaction similar to those found in thylakoid membranes for PQ-9 reduction. The obtained results were discussed in terms of the function of FNR as a ferredoxin:plastoquinone reductase both in cyclic electron transport and chlororespiration.
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Affiliation(s)
- Monika Bojko
- Department of Physiology and Biochemistry of Plants, Faculty of Biotechnology, Jagiellonian University, ul. Gronostajowa 7, 30-387 Kraków, Poland
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Abstract
N-ethylmaleimide (NEM) and N,N'-(1,4-phenylene)dimaleimide (PDM) were discovered to stimulate light-induced oxygen uptake in isolated thylakoids, and PDM provided the same stimulation at one order less concentrations. Oxygen uptake rate increased promptly after NEM or PDM addition to thylakoids. The inhibitors of photosynthetic electron transport as well as catalase decreased this rate close to zero, whereas ascorbate increased it almost three-fold. Dithiothreitol suppressed oxygen uptake stimulated by NEM. NEM stimulated light-induced reduction of cytochrome c, and this stimulation was suppressed by superoxide dismutase. It was concluded that NEM and PDM being reduced can effectively reduce molecules O(2) producing superoxide radicals.
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Affiliation(s)
- Boris Ivanov
- Institute of Basic Biological Problems, Russian Academy of Sciences, Pushchino 142290, Russia.
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17
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Abstract
Chlororespiration has been defined as a respiratory electron transport chain (ETC) in interaction with the photosynthetic ETC in thylakoid membranes of chloroplasts. The existence of chlororespiration has been disputed during the last decade, with the initial evidence mainly obtained with intact algal cells being possibly explained by redox interactions between chloroplasts and mitochondria. The discovery in higher-plant chloroplasts of a plastid-encoded NAD(P)H-dehydrogenase (Ndh) complex, homologous to the bacterial complex I, and of a nuclear-encoded plastid terminal oxidase (PTOX), homologous to the plant mitochondrial alternative oxidase, brought molecular support to the concept of chlororespiration. The functionality of these proteins in non-photochemical reduction and oxidation of plastoquinones (PQs), respectively, has recently been demonstrated. In thylakoids of mature chloroplasts, chlororespiration appears to be a relatively minor pathway compared to linear photosynthetic electron flow from H2O to NADP+. However, chlororespiration might play a role in the regulation of photosynthesis by modulating the activity of cyclic electron flow around photosystem I (PS I). In non-photosynthetic plastids, chlororespiratory electron carriers are more abundant and may play a significant bioenergetic role.
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Affiliation(s)
- Gilles Peltier
- Laboratoire d'Ecophysiologie de la Photosynthèse, Département d'Ecophysiologie Végétale et de Microbiologie, UMR 163 CNRS-CEA, Université Mediterranée, CEA 1000, F-13108 Saint-Paul-lez-Durance, France.
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De Wolf F, Galmiche J, Kraayenhof R, Girault G. Single-turnover flash-induced ATP synthesis in photosystem I-enriched subchloroplast vesicles. FEBS Lett 2001. [DOI: 10.1016/0014-5793(85)80123-x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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19
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Clark R, Hawkesford M, Coughlan S, Bennett J, Hind G. Association of ferredoxin-NADP+
oxidoreductase with the chloroplast cytochrome b-f
complex. FEBS Lett 2001. [DOI: 10.1016/0014-5793(84)81092-3] [Citation(s) in RCA: 83] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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21
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O'Keefe DP. Sites of cytochromeb-563 reduction, and the mode of action of DNP-INT and DBMIB in the chloroplast cytochromeb-563/fcomplex. FEBS Lett 2001. [DOI: 10.1016/0014-5793(83)80786-8] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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22
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de Wolf F, Galmiche J, Kraayenhof R. The antimycin sensitivity of flash-induced ATP synthesis in photosystem I-enriched subchloroplast vesicles. FEBS Lett 2001. [DOI: 10.1016/0014-5793(88)81279-1] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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23
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Krendeleva TE, Kukarskikh GP, Timofeev KN, Ivanov BN, Rubin AB. Ferredoxin-NADP reductase is involved in the ferredoxin-dependent cyclic electron transport in isolated thylakoids. DOKL BIOCHEM BIOPHYS 2001; 379:265-8. [PMID: 11605341 DOI: 10.1023/a:1011650702318] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Affiliation(s)
- T E Krendeleva
- Moscow State University, Vorob'evy gory, Moscow, 119899 Russia
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24
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van Thor JJ, Jeanjean R, Havaux M, Sjollema KA, Joset F, Hellingwerf KJ, Matthijs HC. Salt shock-inducible photosystem I cyclic electron transfer in Synechocystis PCC6803 relies on binding of ferredoxin:NADP(+) reductase to the thylakoid membranes via its CpcD phycobilisome-linker homologous N-terminal domain. BIOCHIMICA ET BIOPHYSICA ACTA 2000; 1457:129-44. [PMID: 10773158 DOI: 10.1016/s0005-2728(00)00072-4] [Citation(s) in RCA: 75] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Relative to ferredoxin:NADP(+) reductase (FNR) from chloroplasts, the comparable enzyme in cyanobacteria contains an additional 9 kDa domain at its amino-terminus. The domain is homologous to the phycocyanin associated linker polypeptide CpcD of the light harvesting phycobilisome antennae. The phenotypic consequences of the genetic removal of this domain from the petH gene, which encodes FNR, have been studied in Synechocystis PCC 6803. The in frame deletion of 75 residues at the amino-terminus, rendered chloroplast length FNR enzyme with normal functionality in linear photosynthetic electron transfer. Salt shock correlated with increased abundance of petH mRNA in the wild-type and mutant alike. The truncation stopped salt stress-inducible increase of Photosystem I-dependent cyclic electron flow. Both photoacoustic determination of the storage of energy from Photosystem I specific far-red light, and the re-reduction kinetics of P700(+), suggest lack of function of the truncated FNR in the plastoquinone-cytochrome b(6)f complex reductase step of the PS I-dependent cyclic electron transfer chain. Independent gold-immunodecoration studies and analysis of FNR distribution through activity staining after native polyacrylamide gelelectrophoresis showed that association of FNR with the thylakoid membranes of Synechocystis PCC 6803 requires the presence of the extended amino-terminal domain of the enzyme. The truncated DeltapetH gene was also transformed into a NAD(P)H dehydrogenase (NDH1) deficient mutant of Synechocystis PCC 6803 (strain M55) (T. Ogawa, Proc. Natl. Acad. Sci. USA 88 (1991) 4275-4279). Phenotypic characterisation of the double mutant supported our conclusion that both the NAD(P)H dehydrogenase complex and FNR contribute independently to the quinone cytochrome b(6)f reductase step in PS I-dependent cyclic electron transfer. The distribution, binding properties and function of FNR in the model cyanobacterium Synechocystis PCC 6803 will be discussed.
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Affiliation(s)
- J J van Thor
- E.C. Slater Institute, University of Amsterdam, Nieuwe Achtergracht 127, 1018 WS, Amsterdam, The Netherlands
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25
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Martínez-Júlvez M, Hurley JK, Tollin G, Gómez-Moreno C, Fillat MF. Overexpression in E. coli of the complete petH gene product from Anabaena: purification and properties of a 49 kDa ferredoxin-NADP+ reductase. BIOCHIMICA ET BIOPHYSICA ACTA 1996; 1297:200-6. [PMID: 8917622 DOI: 10.1016/s0167-4838(96)00024-6] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
The complete petH gene product from Anabaena PCC 7119 has been overexpressed in E. coli and purified in order to determine the influence of the N-terminal extension on the interaction of ferredoxin-NADP+ reductase with its substrates. The intact 49 kDa FNR can be easily purified in a two-step procedure using batch extraction with DEAE-cellulose followed by Cibacron blue-Sepharose chromatography of the proteins unbound to DEAE. Isoelectric focusing of FNR shows several forms, with the major band at pH 6.26. The presence of the N-terminal extension increases the K(m) of FNR for NADPH by 4-fold and by 16.4-fold in the reduction reactions of DCPIP and cytochrome c. However, the K(m) for ferredoxin is 12-fold lower in the reaction catalyzed by the 49 kDa FNR than with the 36 kDa protein. This indicates that the presence of the third domain favours the interaction of FNR with ferredoxin, possibly due to the more positive net charge of the N-terminal extension. Comparable rate constants for both enzymes, were obtained for the photoreduction of NADP+ using photosynthetic membranes and also using rapid kinetic techniques. Slightly different ionic strength dependences of the rate constants were obtained, nevertheless, for both forms of the enzyme. These are a consequence of the structural differences that the proteins show at the N-terminal and of their effect on the interaction with ferredoxin.
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Affiliation(s)
- M Martínez-Júlvez
- Departamento de Bioquímica y Biología Molecular y Celular, Universidad de Zaragoza, Spain
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26
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Bendall DS, Manasse RS. Cyclic photophosphorylation and electron transport. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 1995. [DOI: 10.1016/0005-2728(94)00195-b] [Citation(s) in RCA: 149] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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27
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Kobayashi Y, Heber U. Rates of vectorial proton transport supported by cyclic electron flow during oxygen reduction by illuminated intact chloroplasts. PHOTOSYNTHESIS RESEARCH 1994; 41:419-28. [PMID: 24310156 DOI: 10.1007/bf02183044] [Citation(s) in RCA: 27] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/04/1993] [Accepted: 06/01/1994] [Indexed: 05/09/2023]
Abstract
The light-dependent quenching of 9-aminoacridine fluorescence was used to monitor the state of the transthylakoid proton gradient in illuminated intact chloroplasts in the presence or absence of external electron acceptors. The absence of appreciable light-dependent fluorescence quenching under anaerobic conditions indicated inhibition of coupled electron transport in the absence of external electron acceptors. Oxygen relieved this inhibition. However, when DCMU inhibited excessive reduction of the plastoquinone pool in the absence of oxygen, coupled cyclic electron transport supported the formation of a transthylakoid proton gradient even under anaerobiosis. This proton gradient collapsed in the presence of oxygen. Under aerobic conditions, and when KCN inhibited ribulose bisphosphate carboxylase and ascorbate peroxidase, fluorescence quenching indicated the formation of a transthylakoid proton gradient which was larger with oxygen in the Mehler reaction as electron acceptor than with methylviologen at similar rates of linear electron transport. Apparently, cyclic electron transport occured simultaneously with linear electron transport, when oxygen was available as electron acceptor, but not when methylviologen accepted electrons from Photosystem I. The ratio of cyclic to linear electron transport could be increased by low concentrations of DCMU. This shows that even under aerobic conditions cyclic electron transport is limited in isolated intact chloroplasts by excessive reduction of electron carriers. In fact, P700 in the reaction center of Photosystem I remained reduced in illuminated isolated chloroplasts under conditions which resulted in extensive oxidation of P700 in leaves. This shows that regulation of Photosystem II activity is less effective in isolated chloroplasts than in leaves. Assuming that a Q-cycle supports a H(+)/e ratio of 3 during slow linear electron transport, vectorial proton transport coupled to Photosystem I-dependent cyclic electron flow could be calculated. The highest calculated rate of Photosystem I-dependent proton transport, which was not yet light-saturated, was 330 μmol protons (mg chlorophyll h)(-1) in intact chloroplasts. If H(+)/e is not three but two proton transfer is not 330 but 220 μmol (mg Chl H)(-1). Differences in the regulation of cyclic electron transport in isolated chloroplasts and in leaves are discussed.
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Affiliation(s)
- Y Kobayashi
- Department of Forestry, Faculty of Agriculture, Kyushu University, Hakozaki, 812, Higashi-ku, Fukuoka, Japan
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28
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Manasse RS, Bendall DS. Characteristics of cyclic electron transport in the cyanobacterium Phormidium laminosum. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 1993. [DOI: 10.1016/0005-2728(93)90240-g] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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29
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Cleland RE, Bendall DS. Photosystem I cyclic electron transport: Measurement of ferredoxin-plastoquinone reductase activity. PHOTOSYNTHESIS RESEARCH 1992; 34:409-18. [PMID: 24408836 DOI: 10.1007/bf00029815] [Citation(s) in RCA: 44] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/26/1992] [Accepted: 06/09/1992] [Indexed: 05/08/2023]
Abstract
Absorbance changes of ferredoxin measured at 463 nm in isolated thylakoids were shown to arise from the activity of the enzyme ferredoxin-plastoquinone reductase (FQR) in cyclic electron transport. Under anaerobic conditions in the presence of DCMU and an appropriate concentration of reduced ferredoxin, a light-induced absorbance decrease due to further reduction of Fd was assigned to the oxidation of the other components in the cyclic pathway, primarily plastoquinone. When the light was turned off, Fd was reoxidised and this gave a direct quantitative measurement of the rate of cyclic electron transport due to the activity of FQR. This activity was sensitive to the classical inhibitor of cyclic electron transport, antimycin, and also to J820 and DBMIB. Antimycin had no effect on Fd reduction although this was inhibited by stigmatellin. This provides further evidence that there is a quinone reduction site outside the cytochrome bf complex. The effect of inhibitors of ferredoxin-NADP(+) reductase and experiments involving the modification of ferredoxin suggest that there may be some role for the reductase as a component of FQR. Contrary to expectations, NADPH2 inhibited FQR activity; ATP and ADP had no effect.
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Affiliation(s)
- R E Cleland
- Department of Biochemistry, University of Cambridge, Tennis Court Road, CB2 1QW, Cambridge, UK
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30
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Medina M, Gomez-Moreno C, Tollin G. Effects of chemical modification of Anabaena flavodoxin and ferredoxin-NADP+ reductase on the kinetics of interprotein electron transfer reactions. EUROPEAN JOURNAL OF BIOCHEMISTRY 1992; 210:577-83. [PMID: 1459139 DOI: 10.1111/j.1432-1033.1992.tb17457.x] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
The influence of chemical modification of arginine residues (using phenylglyoxal) in ferredoxin-NADP+ reductase (FNR), and of carboxyl groups (using glycine ethyl ester) in flavodoxin (Fld), on the kinetics of electron transfer between FNR and Fld, and between ferredoxin (Fd) and FNR, was examined using laser flash photolysis methods. All proteins were obtained from the cyanobacterium Anabaena PCC7119. Reduction by laser-generated 5-deazariboflavin semiquinone of the FAD moiety of phenylglyoxal-modified FNR occurred with a second-order rate constant 2.5-fold smaller than that obtained for reduction of native FNR, indicating either a small degree of steric hindrance of the cofactor, or a decrease in its redox potential, upon chemical modification. In contrast, no changes were found in the kinetics of reduction of the FMN cofactor of Fld modified by glycine ethyl ester as compared with the native protein. The observed rate constants for reoxidation of Fdred (reduced Fd) by FNRox (oxidized FNR) were dramatically decreased (approximately 100-fold) when phenylglyoxal-modified FNR was used. In contrast to the reaction involving the native proteins, no ionic strength effects on kobs values were found. These results, and those obtained upon varying the protein concentration, indicate that the rate constant for complex formation and the attractive electrostatic interaction between the two proteins were greatly diminished by chemical modification of arginine residues of FNR. When phenylglyoxal-modified FNRsq (FNR semiquinone) was used to reduce Fldox (oxidized Fld), similar inhibitory effects were observed. In this case, the limiting first-order rate constant for Fldsq (Fld semiquinone) formation via intracomplex electron transfer from FNRsq was approximately 12-fold smaller than that obtained for the native FNR (600 s-1 vs 7000 s-1). Again, ionic strength effects were diminished. The glycine-ethyl-ester-modified Fld yielded a limiting first-order rate constant for intracomplex electron transfer from FNRsq to Fldox which was approximately 7-fold smaller (1000 s-1) than that obtained with native Fld, and ionic strength effects were again diminished. These results indicate that complex formation can still occur between modified FNR and native Fld, and between native FNR and modified Fld, but that the geometry of these complexes is altered so as to decrease the effectiveness of interprotein electron transfer. The results are discussed in terms of the specific structural features of the proteins involved.
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Affiliation(s)
- M Medina
- Departamento de Bioquímica y Biología Molecular y Celular, Facultad de Ciencias, Universidad de Zaragoza, Spain
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31
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Rogers WJ, Hodges M, Decottignies P, Schmitter JM, Gadal P, Jacquot JP. Isolation of a cDNA fragment coding for Chlamydomonas reinhardtii ferredoxin and expression of the recombinant protein in Escherichia coli. FEBS Lett 1992; 310:240-5. [PMID: 1327872 DOI: 10.1016/0014-5793(92)81340-r] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
A cDNA clone coding for mature C. reinhardtii ferredoxin has been isolated from a cDNA library using PCR and two oligonucleotide primers based on the N- and C-termini of the protein's amino acid sequence. The nucleotidic sequence of the PCR fragment (299 bp) agreed well with the amino acid sequence since a single conservative substitution (Thr-7 to Ser) could be deduced. The PCR fragment was inserted into the expression vector pTrc 99A, using the incorporated NcoI and BamHI restriction sites and the construction used to transform E. coli (DH5 alpha F'). After subsequent large scale expression and purification of the recombinant protein, biochemical and biophysical analysis have indicated that the product isolated from E. coli is homologous to native ferredoxin isolated from green algae.
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Affiliation(s)
- W J Rogers
- Laboratoire de Physiologie Végétale Moléculaire, Université de Paris Sud, UA 1128 CNRS, Orsay, France
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Fillat MF, Bakker HA, Weisbeek PJ. Sequence of the ferredoxin-NADP(+)-reductase gene from Anabaena PCC 7119. Nucleic Acids Res 1990; 18:7161. [PMID: 2124680 PMCID: PMC332807 DOI: 10.1093/nar/18.23.7161] [Citation(s) in RCA: 40] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Affiliation(s)
- M F Fillat
- Department of Molecular Cell Biology, State University of Utrecht, The Netherlands
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34
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Aliverti A, Jansen T, Zanetti G, Ronchi S, Herrmann RG, Curti B. Expression in Escherichia coli of ferredoxin:NADP+ reductase from spinach. Bacterial synthesis of the holoflavoprotein and of an active enzyme form lacking the first 28 amino acid residues of the sequence. EUROPEAN JOURNAL OF BIOCHEMISTRY 1990; 191:551-5. [PMID: 2202597 DOI: 10.1111/j.1432-1033.1990.tb19156.x] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
A cDNA clone for the preprotein of spinach ferredoxin:NADP+ reductase has been modified to allow the expression in Escherichia coli of the mature flavoprotein form the lacks the transit peptide. An expression vector, pFNR1, was constructed by subcloning the fragment into the plasmid pDS12/RBSII, SphI. In the crude extracts of transformed cells after induction, two active holoproteins of 35 kDa and 32 kDa, respectively, were found. The 32-kDa protein, purified by immunoaffinity chromatography, was found to lack the first 28 residues of the spinach protein sequence and to have a methionine as the N-terminal residue instead of Val29. A new expression plasmid, pFNR2, was obtained by in vitro mutagenesis of the codon GTG for Val29 to the synonymous GTT; in this case, only the 35-kDa protein was expressed by transformed cells. Both the 35-kDa and 32-kDa enzymes were purified and characterized. All the properties analyzed of the cloned 35-kDa enzyme were very similar to those of the spinach flavoprotein. The 32-kDa form showed the same catalytic efficiency of the spinach enzyme as a diaphorase but its interaction with oxidized ferredoxin was partially impaired.
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Affiliation(s)
- A Aliverti
- Dipartmento di Fisiologia e Biochimica Generali, Università di Milano, Italy
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35
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de Wolf F, Krab K, Visschers R, de Waard J, Kraayenhof R. Studies on well-coupled Photosystem I-enriched subchloroplast vesicles — characteristics and reinterpretation of single-turnover cyclic electron transfer. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 1988. [DOI: 10.1016/0005-2728(88)90026-6] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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36
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Scherer S, Alpes I, Sadowski H, Böger P. Ferredoxin-NADP+ oxidoreductase is the respiratory NADPH dehydrogenase of the cyanobacterium Anabaena variabilis. Arch Biochem Biophys 1988; 267:228-35. [PMID: 2461678 DOI: 10.1016/0003-9861(88)90027-6] [Citation(s) in RCA: 32] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
The NADPH dehydrogenase of the cyanobacterium Anabaena variabilis was solubilized, purified, and characterized. Activity staining after nondenaturing polyacrylamide gel electrophoresis, kinetics, and immunological characterization led to the conclusion that only one thylakoid-associated NADPH dehydrogenase exists in Anabaena, identical with ferredoxin-NADP+ oxidoreductase (FNR). After sodium dodecyl sulfate-polyacrylamide gel electrophoresis an intense band at 34 kDa and a weak band at 52 kDa were found by immunoblotting with an antibody against Anabaena FNR. Using a cell-free preparation competent of oxidative phosphorylation it was demonstrated that FNR operates as a respiratory NADPH dehydrogenase coupled to cyanide-sensitive oxidative ATP formation.
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Affiliation(s)
- S Scherer
- Lehrstuhl für Physiologie und Biochemie der Pflanzen Universität Konstanz, West Germany
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37
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Newman BJ, Gray JC. Characterisation of a full-length cDNA clone for pea ferredoxin-NADP(+) reductase. PLANT MOLECULAR BIOLOGY 1988; 10:511-520. [PMID: 24277623 DOI: 10.1007/bf00033606] [Citation(s) in RCA: 63] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/15/1987] [Accepted: 02/12/1988] [Indexed: 06/02/2023]
Abstract
Ferredoxin-NADP(+) reductase has been purified to homogeneity from pea leaves and has been resolved into two forms by ion exchange chromatography and SDS gel electrophoresis. Antibodies to the proteins have been used to isolate pea leaf cDNA clones from a library in λgt11. A full-length clone of 1 400 bp encodes a polypeptide of 360 amino acid residues, of which 52 residues constitute an N-terminal transit peptide and 308 residues make up the mature protein. Transcription and translation of the cDNA in vitro produces a protein of 40 kDa, which is imported by isolated pea chloroplasts and processed to the mature 34 kDa protein. Southern hybridisation to pea genomic DNA indicates that there are probably two genes in the haploid genome.
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Affiliation(s)
- B J Newman
- Botany School, University of Cambridge, CB2 3EA, Cambridge, UK
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38
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O'Keefe DP. Structure and function of the chloroplast cytochrome bf complex. PHOTOSYNTHESIS RESEARCH 1988; 17:189-216. [PMID: 24429768 DOI: 10.1007/bf00035448] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/01/1987] [Accepted: 02/02/1988] [Indexed: 06/03/2023]
Abstract
The chloroplast cytochrome bf complex is an intrinsic multisubunit protein from the thylakoid membrane consisting of four polypeptides: cytochrome f, a two heme containing cytochrome b 6, the Rieske iron-sulfur protein, and a 17 kD polypeptide of undefined function. The complex functions in electron transfer between PSII and PSI, where most mechanisms suggest that the transfer of a single reducing equivalent from plastoquinol to plastocyanin results in the translocation of two protons across the membrane. Primary sequence analyses, dichroism studies, and functional considerations allow the construction of an approximate structural model of a monomeric complex, although some evidence exists for a dimeric structure. Resolution of the properties of the two cytochrome b 6 hemes has relied upon the availability of purified solubilized complex, while evidence in the thylakoid suggests the difference between the two hemes are not as great in situ. Such variability in the spectroscopic and electrochemical properties of the cytochrome b 6 is a major concern during the experimental use of the purified complex. There is a general consensus that the complex contains a plastoquinol oxidizing (Qz) site, although the evidence for a plastoquinone reduction (Qc) site, called for in most mechanistic hypotheses, is less substantive. Probably the most severe challenge to the so called Q-cycle mechanism comes from experimental observations made with cytochrome b 6 initially reduced, where proposed interpretations more closely resemble a b-cycle than a Q-cycle. Although functional during cyclic electron transfer, the role of the complex and its possible interaction with other proteins, has not been completely resolved.
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Affiliation(s)
- D P O'Keefe
- Central Research and Development Department, E.I. duPont de Nemours and Company, Inc. Experimental Station, Bldg. 402, 19898, Wilmington, DE, USA
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39
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Willey DL, Gray JC. Synthesis and assembly of the cytochrome b-f complex in higher plants. PHOTOSYNTHESIS RESEARCH 1988; 17:125-144. [PMID: 24429665 DOI: 10.1007/bf00047685] [Citation(s) in RCA: 25] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/11/1987] [Accepted: 01/05/1988] [Indexed: 06/03/2023]
Abstract
The cytochrome b-f complex is composed of four polypeptide subunits, three of which, cytochrome f, cytochrome b-563 and subunit IV, are encoded in chloroplast DNA and synthesised within the chloroplast, and the fourth, the Rieske FeS protein, is encoded in nuclear DNA and synthesised in the cytoplasm. The assembly of the cytochrome b-f complex therefore requires the interaction of subunits encoded by different genomes. A key role for the nuclear-encoded Rieske FeS protein in the assembly of the complex is suggested by a study of cytochrome b-f complex mutants. The assembly of individual subunits of the complex may be regulated by the availability of prosthetic groups. The genes for the chloroplast-encoded subunits and cDNA clones for the Rieske FeS protein have been isolated and characterised. Cytochrome f and the Rieske FeS protein are synthesised initially with N-terminal presequences required for their correct assembly within the chloroplast. The deduced amino acid sequences of the four subunits have been used to suggest models for the arrangement of the polypeptides in the thylakoid membrane.
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Affiliation(s)
- D L Willey
- Botany School, University of Cambridge, Downing Street, CB2 3EA, Cambridge, UK
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Chapter 14 Genetics and synthesis of chloroplast membrane proteins. ACTA ACUST UNITED AC 1987. [DOI: 10.1016/s0167-7306(08)60145-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/24/2023]
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Removal of ferredoxin:NADP+ oxidoreductase from thylakoid membranes, rebinding to depleted membranes, and identification of the binding site. J Biol Chem 1986. [DOI: 10.1016/s0021-9258(18)67216-3] [Citation(s) in RCA: 64] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
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Coughlan S, Matthijs HC, Hind G. The ferredoxin-NADP+ oxidoreductase-binding protein is not the 17-kDa component of the cytochrome b/f complex. J Biol Chem 1985. [DOI: 10.1016/s0021-9258(18)95675-9] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
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Kinetics of the flash-induced electrochromic absorbance change in the presence of background illumination. Turnover rate of the electron transport. I. Isolated intact chloroplasts. J Bioenerg Biomembr 1985. [DOI: 10.1007/bf00743108] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Schrautemeier B, Böhme H, Böger P. Reconstitution of a light-dependent nitrogen-fixing and transhydrogenase system with heterocyst thylakoids. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 1985. [DOI: 10.1016/0005-2728(85)90118-5] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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Alpes I, Schrautemeier B, Scherer S, Böger P. Different enzymes involved in NADH- and NADPH-dependent respiration in the cyanobacteriumAnabaena variabilis. FEMS Microbiol Lett 1985. [DOI: 10.1111/j.1574-6968.1985.tb01582.x] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
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Moss DA, Bendall DS. Cyclic electron transport in chloroplasts. The Q-cycle and the site of action of antimycin. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 1984. [DOI: 10.1016/0005-2728(84)90036-7] [Citation(s) in RCA: 110] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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Schrautemeier B, B�hme H, B�ger P. In vitro studies on pathways and regulation of electron transport to nitrogenase with a cell-free extract from heterocysts of Anabaena variabilis. Arch Microbiol 1984. [DOI: 10.1007/bf00425801] [Citation(s) in RCA: 35] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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Studies on well coupled Photosystem I-enriched subchloroplast vesicles. Optimization of ferredoxin-mediated cyclic photophosphorylation and electric potential generation. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 1983. [DOI: 10.1016/0005-2728(83)90037-3] [Citation(s) in RCA: 37] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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Garab G, Farineau J. Is antimycin A a specific inhibitor of the slow rise of the electrochromic absorbance change in intact chloroplasts? Biochem Biophys Res Commun 1983; 111:619-23. [PMID: 6838576 DOI: 10.1016/0006-291x(83)90351-0] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
The inhibitory effect of antimycin A on the slow rise of the flash-induced electrochromic absorbance change was reinvestigated in intact chloroplasts isolated from pea leaves. It is shown that in the absence of nigericin and +K at low repetition rates (less than 0.5 s-1) of the excitation flashes not only the slow (approximately 10 ms) rise but also the initial (much less than 1 ms) rise generated by photosystem 1 is inhibited by antimycin A.
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Carrillo N, Vallejos RH. The light-dependent modulation of photosynthetic electron transport. Trends Biochem Sci 1983. [DOI: 10.1016/0968-0004(83)90389-4] [Citation(s) in RCA: 30] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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