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Buchert F, Bailleul B, Joliot P. Disentangling chloroplast ATP synthase regulation by proton motive force and thiol modulation in Arabidopsis leaves. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2021; 1862:148434. [PMID: 33932368 DOI: 10.1016/j.bbabio.2021.148434] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Received: 12/11/2020] [Revised: 04/06/2021] [Accepted: 04/20/2021] [Indexed: 11/29/2022]
Abstract
The chloroplast ATP synthase (CF1Fo) contains a specific feature to the green lineage: a γ-subunit redox domain that contains a cysteine couple which interacts with the torque-transmitting βDELSEED-loop. This thiol modulation equips CF1Fo with an important environmental fine-tuning mechanism. In vitro, disulfide formation in the γ-redox domain slows down the activity of the CF1Fo at low transmembrane electrochemical proton gradient ( [Formula: see text] ), which agrees with its proposed role as chock based on recently solved structure. The γ-dithiol formation at the onset of light is crucial to maximize photosynthetic efficiency since it lowers the [Formula: see text] activation level for ATP synthesis in vitro. Here, we validate these findings in vivo by utilizing absorption spectroscopy in Arabidopsis thaliana. To do so, we monitored the [Formula: see text] present in darkness and identified its mitochondrial sources. By following the fate and components of light-induced extra [Formula: see text] , we estimated the ATP lifetime that lasted up to tens of minutes after long illuminations. Based on the relationship between [Formula: see text] and CF1Fo activity, we conclude that the dithiol configuration in vivo facilitates photosynthesis by driving the same ATP synthesis rate at a significative lower [Formula: see text] than in the γ-disulfide state. The presented in vivo findings are an additional proof of the importance of CF1Fo thiol modulation, reconciling biochemical in vitro studies and structural insights.
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Affiliation(s)
- Felix Buchert
- Laboratory of Chloroplast Biology and Light-Sensing in Microalgae - UMR7141, IBPC, CNRS-Sorbonne Université, Paris, France; Institute of Plant Biology and Biotechnology, University of Münster, Schlossplatz 8, 48143 Münster, Germany.
| | - Benjamin Bailleul
- Laboratory of Chloroplast Biology and Light-Sensing in Microalgae - UMR7141, IBPC, CNRS-Sorbonne Université, Paris, France
| | - Pierre Joliot
- Laboratory of Chloroplast Biology and Light-Sensing in Microalgae - UMR7141, IBPC, CNRS-Sorbonne Université, Paris, France
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Hisabori T, Sunamura EI, Kim Y, Konno H. The chloroplast ATP synthase features the characteristic redox regulation machinery. Antioxid Redox Signal 2013; 19:1846-54. [PMID: 23145525 PMCID: PMC3837435 DOI: 10.1089/ars.2012.5044] [Citation(s) in RCA: 64] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
SIGNIFICANCE Regulation of the activity of the chloroplast ATP synthase is largely accomplished by the chloroplast thioredoxin system, the main redox regulation system in chloroplasts, which is directly coupled to the photosynthetic reaction. We review the current understanding of the redox regulation system of the chloroplast ATP synthase. RECENT ADVANCES The thioredoxin-targeted portion of the ATP synthase consists of two cysteines located on the central axis subunit γ. The redox state of these two cysteines is under the influence of chloroplast thioredoxin, which directly controls rotation during catalysis by inducing a conformational change in this subunit. The molecular mechanism of redox regulation of the chloroplast ATP synthase has recently been determined. CRITICAL ISSUES Regulation of the activity of the chloroplast ATP synthase is critical in driving efficiency into the ATP synthesis reaction in chloroplasts. FUTURE DIRECTIONS The molecular architecture of the chloroplast ATP synthase, which confers redox regulatory properties requires further investigation, in light of the molecular structure of the enzyme complex as well as the physiological significance of the regulation system.
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Affiliation(s)
- Toru Hisabori
- 1 Chemical Resources Laboratory, Tokyo Institute of Technology , Yokohama, Japan
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Buchert F, Forreiter C. Singlet oxygen inhibits ATPase and proton translocation activity of the thylakoid ATP synthase CF1CFo. FEBS Lett 2010; 584:147-52. [PMID: 19925794 DOI: 10.1016/j.febslet.2009.11.040] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2009] [Revised: 10/30/2009] [Accepted: 11/12/2009] [Indexed: 11/26/2022]
Abstract
Singlet oxygen ((1)O(2)) produced in plants during photosynthesis has a strong damaging effect not only on both photosystems but also on the whole photosynthetic machinery. This is also applicable for the adenosine triphosphate (ATP) synthase. Here we describe the impact of (1)O(2) generated by the photosensitizer Rose Bengal on the ATP hydrolysis and ATP-driven proton translocation activity of CF1CFo. Both activities were reduced dramatically within 1min of exposure. Interestingly, it is shown that oxidized thylakoid ATP synthase is more susceptible to (1)O(2) than CF1CFo in its reduced state, a new insight on the mechanism of (1)O(2) interaction with the gamma subunit.
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Affiliation(s)
- Felix Buchert
- Pflanzenphysiologie, Justus-Liebig Universität, Zeughaus, Giessen, Germany
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4
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Structural and functional analysis of the intrinsic inhibitor subunit epsilon of F1-ATPase from photosynthetic organisms. Biochem J 2009; 425:85-94. [PMID: 19785575 DOI: 10.1042/bj20091247] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
The epsilon subunit, a small subunit located in the F1 domain of ATP synthase and comprising two distinct domains, an N-terminal beta-sandwich structure and a C-terminal alpha-helical region, serves as an intrinsic inhibitor of ATP hydrolysis activity. This inhibitory function is especially important in photosynthetic organisms as the enzyme cannot synthesize ATP in the dark, but may catalyse futile ATP hydrolysis reactions. To understand the structure-function relationship of this subunit in F1 from photosynthetic organisms, we solved the NMR structure of the epsilon subunit of ATP synthase obtained from the thermophilic cyanobacterium Thermosynechococcus elongatus BP-1, and examined the flexibility of the C-terminal domains using molecular dynamics simulations. In addition, we revealed the significance of the C-terminal alpha-helical region of the epsilon subunit in determining the binding affinity to the complex based on the assessment of the inhibition of ATPase activity by the cyanobacterial epsilon subunit and the chimaeric subunits composed of the N-terminal domain from the cyanobacterium and the C-terminal domain from spinach. The differences observed in the structural and biochemical properties of chloroplast and bacterial epsilon subunits explains the distinctive characteristics of the epsilon subunits in the ATPase complex of the photosynthetic organism.
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Datiles MJ, Johnson EA, McCarty RE. Inhibition of the ATPase activity of the catalytic portion of ATP synthases by cationic amphiphiles. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2008; 1777:362-8. [DOI: 10.1016/j.bbabio.2008.01.010] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/26/2007] [Revised: 12/05/2007] [Accepted: 01/22/2008] [Indexed: 10/22/2022]
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6
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Regulatory mechanisms of proton-translocating F(O)F (1)-ATP synthase. Results Probl Cell Differ 2007; 45:279-308. [PMID: 18026702 DOI: 10.1007/400_2007_043] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/04/2022]
Abstract
H(+)-F(O)F(1)-ATP synthase catalyzes synthesis of ATP from ADP and inorganic phosphate using the energy of transmembrane electrochemical potential difference of proton (deltamu(H)(+). The enzyme can also generate this potential difference by working as an ATP-driven proton pump. Several regulatory mechanisms are known to suppress the ATPase activity of F(O)F(1): 1. Non-competitive inhibition by MgADP, a feature shared by F(O)F(1) from bacteria, chloroplasts and mitochondria 2. Inhibition by subunit epsilon in chloroplast and bacterial enzyme 3. Inhibition upon oxidation of two cysteines in subunit gamma in chloroplast F(O)F(1) 4. Inhibition by an additional regulatory protein (IF(1)) in mitochondrial enzyme In this review we summarize the information available on these regulatory mechanisms and discuss possible interplay between them.
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McCallum JR, McCarty RE. Proton flux through the chloroplast ATP synthase is altered by cleavage of its gamma subunit. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2007; 1767:974-9. [PMID: 17559799 DOI: 10.1016/j.bbabio.2007.04.008] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/20/2007] [Revised: 04/02/2007] [Accepted: 04/23/2007] [Indexed: 11/21/2022]
Abstract
Electron transport, the proton gradient and ATP synthesis were determined in thylakoids that had been briefly exposed to a low concentration of trypsin during illumination. This treatment cleaves the gamma subunit of the ATP synthase into two large fragments that remain associated with the enzyme. Higher rates of electron transport are required to generate a given value of the proton gradient in the trypsin-treated membranes than in control membranes, indicating that the treated membranes are proton leaky. Since venturicidin restores electron transport and the proton gradient to control levels, the proton leak is through the ATP synthase. Remarkably, the synthesis of ATP by the trypsin-treated membranes at saturating light intensities is only slightly inhibited even though the proton gradient is significantly lower in the treated thylakoids. ATP synthesis and the proton gradient were determined as a function of light intensity in control and trypsin-treated thylakoids. The trypsin-treated membranes synthesized ATP at lower values of the proton gradient than the control membranes. Cleavage of the gamma subunit abrogates inhibition of the activity of the chloroplast ATP synthase by the epsilon subunit. Our results suggest that overcoming inhibition by the epsilon subunit costs energy.
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Affiliation(s)
- Jeremy R McCallum
- Department of Biology, Johns Hopkins University, Baltimore, Maryland 21218, USA
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Berger G, Girault G, Galmiche JM. Application of HPLC to the Study of the Chloroplast Atpase Mg2+Dependent Mechanism. ACTA ACUST UNITED AC 2006. [DOI: 10.1080/01483919008049589] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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McCarty RE. ATP synthase of chloroplast thylakoid membranes: a more in depth characterization of its ATPase activity. J Bioenerg Biomembr 2006; 37:289-97. [PMID: 16341773 DOI: 10.1007/s10863-005-8640-7] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2005] [Accepted: 08/02/2005] [Indexed: 10/25/2022]
Abstract
In contrast to everted mitochondrial inner membrane vesicles and eubacterial plasma membrane vesicles, the ATPase activity of chloroplast ATP synthase in thylakoid membranes is extremely low. Several treatments of thylakoids that unmask ATPase activity are known. Illumination of thylakoids that contain reduced ATP synthase (reduced thylakoids) promotes the hydrolysis of ATP in the dark. Incubation of thylakoids with trypsin can also elicit higher rates of ATPase activity. In this paper the properties of the ATPase activity of the ATP synthase in thylakoids treated with trypsin are compared with those of the ATPase activity in reduced thylakoids. The trypsin-treated membranes have significant ATPase activity in the presence of Ca2+, whereas the Ca2+-ATPase activity of reduced thylakoids is very low. The Mg2+-ATPase activity of the trypsinized thylakoids was only partially inhibited by the uncouplers, at concentrations that fully inhibit the ATPase activity of reduced membranes. Incubation of reduced thylakoids with ADP in Tris buffer prior to assay abolishes Mg2+-ATPase activity. The Mg2+-ATPase activity of trypsin-treated thylakoids was unaffected by incubation with ADP. Trypsin-treated membranes can make ATP at rates that are 75-80% of those of untreated thylakoids. The Mg2+-ATPase activity of trypsin-treated thylakoids is coupled to inward proton translocation and 10 mM sulfite stimulates both proton uptake and ATP hydrolysis. It is concluded that cleavage of the gamma subunit of the ATP synthase by trypsin prevents inhibition of ATPase activity by the epsilon subunit, but only partially overcomes inhibition by Mg2+ and ADP during assay.
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Affiliation(s)
- Richard E McCarty
- Department of Biology, Johns Hopkins University, Baltimore, Maryland, 21218, USA.
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Hisabori T, Ueoka-Nakanishi H, Konno H, Koyama F. Molecular evolution of the modulator of chloroplast ATP synthase: origin of the conformational change dependent regulation. FEBS Lett 2003; 545:71-5. [PMID: 12788494 DOI: 10.1016/s0014-5793(03)00395-8] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Chloroplast ATP synthase synthesizes ATP by utilizing a proton gradient as an energy supply, which is generated by photosynthetic electron transport. The activity of the chloroplast ATP synthase is regulated in several specific ways to avoid futile hydrolysis of ATP under various physiological conditions. Several regulatory signals such as Delta mu H(+), tight binding of ADP and its release, thiol modulation, and inhibition by the intrinsic inhibitory subunit epsilon are sensed by this complex. In this review, we describe the function of two regulatory subunits, gamma and epsilon, of ATP synthase based on their possible conformational changes and discuss the evolutionary origin of these regulation systems.
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Affiliation(s)
- Toru Hisabori
- Chemical Resources Laboratory, Tokyo Institute of Technology, and ATP System Project, Exploratory Research for Advanced Technology, Japan Science and Technology Corporation, Yokohama, Japan.
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Hisabori T, Konno H, Ichimura H, Strotmann H, Bald D. Molecular devices of chloroplast F(1)-ATP synthase for the regulation. BIOCHIMICA ET BIOPHYSICA ACTA 2002; 1555:140-6. [PMID: 12206906 DOI: 10.1016/s0005-2728(02)00269-4] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
In chloroplasts, synthesis of ATP is energetically coupled with the utilization of a proton gradient formed by photosynthetic electron transport. The involved enzyme, the chloroplast ATP synthase, can potentially hydrolyze ATP when the magnitude of the transmembrane electrochemical potential difference of protons (Delta(micro)H(+)) is small, e.g. at low light intensity or in the dark. To prevent this wasteful consumption of ATP, the activity of chloroplast ATP synthase is regulated as the occasion may demand. As regulation systems Delta(micro)H(+) activation, thiol modulation, tight binding of ADP and the role of the intrinsic inhibitory subunit epsilon is well documented. In this article, we discuss recent progress in understanding of the regulation system of the chloroplast ATP synthase at the molecular level.
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Affiliation(s)
- Toru Hisabori
- Chemical Resources Laboratory, Tokyo Institute of Technology, Yokohama, Kanagawa, Japan.
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He X, Miginiac-Maslow M, Sigalat C, Keryer E, Haraux F. Mechanism of activation of the chloroplast ATP synthase. A kinetic study of the thiol modulation of isolated ATPase and membrane-bound ATP synthase from spinach by Eschericia coli thioredoxin. J Biol Chem 2000; 275:13250-8. [PMID: 10788430 DOI: 10.1074/jbc.275.18.13250] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The mechanism of thiol modulation of the chloroplast ATP synthase by Escherichia coli thioredoxin was investigated in the isolated ATPase subcomplex and in the ATP synthase complex reconstituted in bacteriorhodopsin proteoliposomes. Thiol modulation was resolved kinetically by continuously monitoring ATP hydrolysis by the isolated subcomplex and ATP synthesis by proteoliposomes. The binding rate constant of reduced thioredoxin to the oxidized ATPase subcomplex devoid of its epsilon subunit could be determined. It did not depend on the catalytic turnover. Reciprocically, the catalytic turnover did not seem to depend on thioredoxin binding. Thiol modulation by Trx of the epsilon-bearing ATPase subcomplex was slow and favored the release of epsilon. The rate constant of thioredoxin binding to the membrane-bound ATP synthase increased with the protonmotive force. It was lower in the presence of ADP than in its absence, revealing a specific effect of the ATP synthase turnover on thioredoxin-gamma subunit interaction. These findings, and more especially the comparisons between the isolated ATPase subcomplex and the ATP synthase complex, can be interpreted in the frame of the rotational catalysis hypothesis. Finally, thiol modulation changed the catalytic properties of the ATP synthase, the kinetics of which became non-Michaelian. This questions the common view about the nature of changes induced by ATP synthase thiol modulation.
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Affiliation(s)
- X He
- Section de Bioénergétique, Bâtiment 532, and Protéines Membranaires Transductrices d'Energie, CNRS-URA 2096, CEA Saclay, F91191 Gif-sur-Yvette Cedex, France
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Hisabori T, Motohashi K, Kroth P, Strotmann H, Amano T. The formation or the reduction of a disulfide bridge on the gamma subunit of chloroplast ATP synthase affects the inhibitory effect of the epsilon subunit. J Biol Chem 1998; 273:15901-5. [PMID: 9632635 DOI: 10.1074/jbc.273.26.15901] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
We have studied the change of the catalytic activity of chimeric complexes that were formed by chloroplast coupling factor 1 (CF1) -gamma, alpha and beta subunits of thermophilic bacterial F1 after formation or reduction of the disulfide bridge of different gamma subunits modified by oligonucleotide-directed mutagenesis techniques. For this purpose, three mutant gamma subunits were produced: gamma Delta194-230, here 37 amino acids from Pro-194 to Ile-230 are deleted, gammaC199A, Cys-199 is changed to Ala, and gamma Delta200-204, amino acids from Asp-200 to Lys-204 are deleted. All of the chimeric subunit complexes produced from each of these mutant CF1-gamma subunits and alpha and beta subunits from thermophilic bacterial F1 lost the sensitivity against thiol reagents when compared with the complex containing wild-type CF1-gamma. The pH optimum (pH 8.5-9.0) and the concentration of methanol to stimulate ATPase activities were not affected by these mutations. These indicate that the introduction of the mutations did not change the main features of ATPase activity of the chimeric complex. However, the interaction between gamma subunit and epsilon subunit was strongly influenced by the type of gamma subunit itself. Although the ATPase activity of the chimeric complex that contained gamma Delta200-204 or gammaC199A was inhibited by the addition of recombinant epsilon subunit from CF1 similarly to complexes containing the reduced wild-type gamma subunit, the recombinant epsilon subunit did not inhibit the ATPase of the complex, which contained the oxidized form of gamma subunit. Therefore the affinity of the epsilon subunit to the gamma subunit may be dependent on the state of the gamma subunit or the epsilon subunit may bind to the oxidized form of gamma subunit in a mode that does not inhibit the activity. The ATPase activity of the complex that contains gamma Delta194-230 was not efficiently inhibited by epsilon subunit. These results show that the formation or reduction of the disulfide bond on the gamma subunit may induce a conformational change in the region that directly affects the interaction of this subunit with the adjacent epsilon subunit.
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Affiliation(s)
- T Hisabori
- Research Laboratory of Resources Utilization, Tokyo Institute of Technology, Nagatsuta 4259, Midori-ku, Yokohama 226-8503, Japan.
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A role for the disulfide bond spacer region of theChlamydomonas reinhardtii coupling factor 1 γ-subunit in redox regulation of ATP synthase. J Bioenerg Biomembr 1996. [DOI: 10.1007/bf02150678] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Soteropoulos P, Ong A, McCarty R. Alkylation of cysteine 89 of the gamma subunit of chloroplast coupling factor 1 with N-ethylmaleimide alters nucleotide interactions. J Biol Chem 1994. [DOI: 10.1016/s0021-9258(17)32092-6] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
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Bakels RH, van Walraven HS, Krab K, Scholts MJ, Kraayenhof R. On the activation mechanism of the H(+)-ATP synthase and unusual thermodynamic properties in the alkalophilic cyanobacterium Spirulina platensis. EUROPEAN JOURNAL OF BIOCHEMISTRY 1993; 213:957-64. [PMID: 8504834 DOI: 10.1111/j.1432-1033.1993.tb17840.x] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
The activation requirements and thermodynamic characteristics of ATP synthase from the alkalophilic cyanobacterium Spirulina platensis were studied in coupled membrane vesicles. Activation by methanol increased the Vmax, while the Km for MgATP was unaffected (0.7 mM). We propose that in Sp. platensis, as in chloroplasts, the activating effect of methanol is based on perturbation of the gamma-epsilon subunit interaction. Light-driven ATP synthesis by membrane vesicles of Sp. platensis was stimulated by dithiothreitol. The characteristics of the activation of the ATP synthase by the proton electrochemical potential difference (delta mu H+) were analyzed on the basis of the uncoupled rates of ATP hydrolysis as a function of a previously applied proton gradient. Two values of delta mu H+, at which 50% of the enzyme is active, were found; 13-14 kJ.mol-1 for untreated membrane vesicles, and 4-8 kJ.mol-1 for light-treated and dithiothreitol-treated membrane vesicles. These values are lower than the corresponding values for the oxidized and reduced forms, respectively, of the chloroplast enzyme. Although no bulk proton gradient could be observed, membrane vesicles of Sp. platensis were able to maintain an equilibrium phosphate potential (delta Gp) of 40-43.5 kJ.mol-1, comparable to values found for Synechococcus 6716 and Anabaena 7120 membrane vesicles. Acid/base-transition experiments showed that the thermodynamic threshold, delta mu H+, for ATP synthesis, catalyzed by light-treated and dithiothreitol-treated Spirulina membrane vesicles, was less than 5 kJ.mol-1. The activation characteristics and the low thermodynamic threshold allow ATP synthesis to occur at low delta mu H+ values. The findings are discussed, both with respect to differences and similarities with the enzymes from chloroplasts and other cyanobacteria, and with respect to the alkalophilic properties of Sp. platensis.
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Affiliation(s)
- R H Bakels
- Department of Molecular and Cellular Biology, Vrije Universiteit, Amsterdam, The Netherlands
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Modifications of the gamma subunit of chloroplast coupling factor 1 alter interactions with the inhibitory epsilon subunit. J Biol Chem 1992. [DOI: 10.1016/s0021-9258(19)50025-4] [Citation(s) in RCA: 57] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
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Manipulation of the imbalance for linear electron flow activities between photosystems I and II of photosynthesis by cyclic electron flow cofactors. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 1992. [DOI: 10.1016/0005-2728(92)90187-7] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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