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Sugiura M, Kimura M, Shimamoto N, Takegawa Y, Nakamura M, Koyama K, Sellés J, Boussac A, Rutherford AW. Tuning of the Chl D1 and Chl D2 properties in photosystem II by site-directed mutagenesis of neighbouring amino acids. BIOCHIMICA ET BIOPHYSICA ACTA. BIOENERGETICS 2024; 1865:149013. [PMID: 37717932 DOI: 10.1016/j.bbabio.2023.149013] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/11/2023] [Revised: 09/01/2023] [Accepted: 09/11/2023] [Indexed: 09/19/2023]
Abstract
Photosystem II is the water/plastoquinone photo-oxidoreductase of photosynthesis. The photochemistry and catalysis occur in a quasi-symmetrical heterodimer, D1D2, that evolved from a homodimeric ancestor. Here, we studied site-directed mutants in PSII from the thermophilic cyanobacterium Thermosynechoccocus elongatus, focusing on the primary electron donor chlorophyll a in D1, ChlD1, and on its symmetrical counterpart in D2, ChlD2, which does not play a direct photochemical role. The main conserved amino acid specific to ChlD1 is D1/T179, which H-bonds the water ligand to its Mg2+, while its counterpart near ChlD2 is the non-H-bonding D2/I178. The symmetrical-swapped mutants, D1/T179I and D2/I178T, and a second ChlD2 mutant, D2/I178H, were studied. The D1 mutations affected the 686 nm absorption attributed to ChlD1, while the D2 mutations affected a 663 nm feature, tentatively attributed to ChlD2. The mutations had little effect on enzyme activity and forward electron transfer, reflecting the robustness of the overall enzyme function. In contrast, the mutations significantly affected photodamage and protective mechanisms, reflecting the importance of redox tuning in these processes. In D1/T179I, the radical pair recombination triplet on ChlD1 was shared onto a pheophytin, presumably PheD1 and the detection of 3PheD1 supports the proposed mechanism for the anomalously short lifetime of 3ChlD1; e.g. electron transfer quenching by QA- of 3PheD1 after triplet transfer from 3ChlD1. In D2/I178T, a charge separation could occur between ChlD2 and PheD2, a reaction that is thought to occur in ancestral precursors of PSII. These mutants help understand the evolution of asymmetry in PSII.
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Affiliation(s)
- Miwa Sugiura
- Proteo-Science Research Center, Department of Chemistry, Graduate School of Science and Technology, Ehime University, Bunkyo-cho, Matsuyama, Ehime 790-8577, Japan.
| | - Masaya Kimura
- Proteo-Science Research Center, Department of Chemistry, Graduate School of Science and Technology, Ehime University, Bunkyo-cho, Matsuyama, Ehime 790-8577, Japan
| | - Naohiro Shimamoto
- Proteo-Science Research Center, Department of Chemistry, Graduate School of Science and Technology, Ehime University, Bunkyo-cho, Matsuyama, Ehime 790-8577, Japan
| | - Yuki Takegawa
- Proteo-Science Research Center, Department of Chemistry, Graduate School of Science and Technology, Ehime University, Bunkyo-cho, Matsuyama, Ehime 790-8577, Japan
| | - Makoto Nakamura
- Proteo-Science Research Center, Department of Chemistry, Graduate School of Science and Technology, Ehime University, Bunkyo-cho, Matsuyama, Ehime 790-8577, Japan
| | - Kazumi Koyama
- Proteo-Science Research Center, Department of Chemistry, Graduate School of Science and Technology, Ehime University, Bunkyo-cho, Matsuyama, Ehime 790-8577, Japan
| | - Julien Sellés
- Institut de Biologie Physico-Chimique, UMR CNRS 7141 and Sorbonne Université, 13 rue Pierre et Marie Curie, 75005 Paris, France
| | - Alain Boussac
- Institut de Biologie Intégrative de la Cellule, UMR9198, CEA Saclay, 91191 Gif-Sur-Yvette, France.
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Pavlou A, Mokvist F, Styring S, Mamedov F. Far-red photosynthesis: Two charge separation pathways exist in plant Photosystem II reaction center. BIOCHIMICA ET BIOPHYSICA ACTA. BIOENERGETICS 2023; 1864:148994. [PMID: 37355002 DOI: 10.1016/j.bbabio.2023.148994] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/13/2023] [Revised: 06/09/2023] [Accepted: 06/15/2023] [Indexed: 06/26/2023]
Abstract
An alternative charge separation pathway in Photosystem II under the far-red light was proposed by us on the basis of electron transfer properties at 295 K and 5 K. Here we extend these studies to the temperature range of 77-295 K with help of electron paramagnetic resonance spectroscopy. Induction of the S2 state multiline signal, oxidation of Cytochrome b559 and ChlorophyllZ was studied in Photosystem II membrane preparations from spinach after application of a laser flashes in visible (532 nm) or far-red (730-750 nm) spectral regions. Temperature dependence of the S2 state signal induction after single flash at 730-750 nm (Tinhibition ~ 240 K) was found to be different than that at 532 nm (Tinhibition ~ 157 K). No contaminant oxidation of the secondary electron donors cytochrome b559 or chlorophyllZ was observed. Photoaccumulation experiments with extensive flashing at 77 K showed similar results, with no or very little induction of the secondary electron donors. Thus, the partition ratio defined as (yield of YZ/CaMn4O5-cluster oxidation):(yield of Cytb559/ChlZ/CarD2 oxidation) was found to be 0.4 at under visible light and 1.7 at under far-red light at 77 K. Our data indicate that different products of charge separation after far-red light exists in the wide temperature range which further support the model of the different primary photochemistry in Photosystem II with localization of hole on the ChlD1 molecule.
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Affiliation(s)
- Andrea Pavlou
- Molecular Biomimetics, Department of Chemistry-Ångström, Uppsala University, P.O. Box 523, 751 20 Uppsala, Sweden
| | - Fredrik Mokvist
- Molecular Biomimetics, Department of Chemistry-Ångström, Uppsala University, P.O. Box 523, 751 20 Uppsala, Sweden
| | - Stenbjörn Styring
- Molecular Biomimetics, Department of Chemistry-Ångström, Uppsala University, P.O. Box 523, 751 20 Uppsala, Sweden
| | - Fikret Mamedov
- Molecular Biomimetics, Department of Chemistry-Ångström, Uppsala University, P.O. Box 523, 751 20 Uppsala, Sweden.
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3
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Llansola-Portoles MJ, Pascal AA, Robert B. Resonance Raman: A powerful tool to interrogate carotenoids in biological matrices. Methods Enzymol 2022; 674:113-135. [DOI: 10.1016/bs.mie.2022.03.068] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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El-Agamey A, Melø TB, El-Hagrasy MA, Partali V, Fukuzumi S. Carotenoid radical ions: A laser flash photolysis study. JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY. B, BIOLOGY 2020; 212:112023. [PMID: 32980657 DOI: 10.1016/j.jphotobiol.2020.112023] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/06/2020] [Revised: 09/02/2020] [Accepted: 09/04/2020] [Indexed: 10/23/2022]
Abstract
Laser excitation of a single precursor, namely 2-hydroxy-4'-(2-hydroxyethoxy)-2-methylpropiophenone (HHEMP), has been used for generating the radical cations and radical anions of various carotenoids in methanol. In the presence of oxygen, laser excitation of HHEMP undergoes an efficient α-cleavage reaction (Norrish type I) to form acyl radicals, which react with O2, in a nearly diffusion-controlled reaction, to form their corresponding strong oxidizing acylperoxyl radicals (RO2•) (E = ~1.1 V (v SHE)), which are capable of oxidizing almost all carotenoids. Under argon-saturated conditions and in the presence of strong base (0.01 M NaOH or tetrabutylammonium hydroxide (TBAOH)), the initially formed 2-hydroxy-2-propyl radical (ACH•), generated after LFP of HHEMP, is deprotonated to form the strong reducing acetone ketyl radical (AC•-) (E {acetone/ AC•-} = -2.1 V (v SHE)), which is capable of reducing all carbonyl-containing carotenoids. To validate this new proposed approach, retinal and β-apo-8'-carotenal (APO), with known spectroscopic data, were investigated in methanol, acetonitrile and tetrahydrofuran (THF). In addition, the radical ions of newly investigated carotenoids, namely 4-oxo-β-apo-15'-carotenoic acid (4-oxo-15'), crocetindial, 4-oxo-β-apo-10'-carotenoic acid ethyl ester (4-oxo-10') and 4-oxo-β-apo-8'-carotenoic acid ethyl ester (4-oxo-8') have been reported. Moreover, the scope of this approach has been extended to investigate the radical ions of chlorophyll b.
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Affiliation(s)
- Ali El-Agamey
- Department of Physics, Norwegian University of Science and Technology (NTNU), N-7491 Trondheim, Norway; Chemistry Department, Faculty of Science, Damietta University, New Damietta, Damietta, Egypt; Department of Chemistry, Faculty of Science, King Faisal University, Al-Ahsa, Saudi Arabia.
| | - Thor B Melø
- Department of Physics, Norwegian University of Science and Technology (NTNU), N-7491 Trondheim, Norway
| | - Maha A El-Hagrasy
- Chemistry Department, Faculty of Science, Damietta University, New Damietta, Damietta, Egypt
| | - Vassilia Partali
- Department of Chemistry, Norwegian University of Science and Technology (NTNU), N-7491 Trondheim, Norway
| | - Shunichi Fukuzumi
- Department of Chemistry and Nano Science, Ewha Womans University, Seoul 120-750, Republic of Korea; Faculty of Science and Technology, Meijo University, ALCA and SENTAN, Japan Science and Technology Agency (JST), Nagoya, Aichi 468-8502, Japan
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Khorobrykh A. Hydrogen Peroxide and Superoxide Anion Radical Photoproduction in PSII Preparations at Various Modifications of the Water-Oxidizing Complex. PLANTS 2019; 8:plants8090329. [PMID: 31491946 PMCID: PMC6784185 DOI: 10.3390/plants8090329] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/30/2019] [Revised: 08/25/2019] [Accepted: 08/29/2019] [Indexed: 11/24/2022]
Abstract
The photoproduction of superoxide anion radical (O2−•) and hydrogen peroxide (H2O2) in photosystem II (PSII) preparations depending on the damage to the water-oxidizing complex (WOC) was investigated. The light-induced formation of O2−• and H2O2 in the PSII preparations rose with the increased destruction of the WOC. The photoproduction of superoxide both in the PSII preparations holding intact WOC and the samples with damage to the WOC was approximately two times higher than H2O2. The rise of O2−• and H2O2 photoproduction in the PSII preparations in the course of the disassembly of the WOC correlated with the increase in the fraction of the low-potential (LP) Cyt b559. The restoration of electron flow in the Mn-depleted PSII preparations by exogenous electron donors (diphenylcarbazide, Mn2+) suppressed the light-induced formation of O2−• and H2O2. The decrease of O2−• and H2O2 photoproduction upon the restoration of electron transport in the Mn-depleted PSII preparations could be due to the re-conversion of the LP Cyt b559 into higher potential forms. It is supposed that the conversion of the high potential Cyt b559 into its LP form upon damage to the WOC leads to the increase of photoproduction of O2−• and H2O2 in PSII.
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Affiliation(s)
- Andrey Khorobrykh
- Institute of Basic Biological Problems, FRC PSCBR RAS, Pushchino 142290, Moscow Region, Russia.
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Cardona T, Sánchez‐Baracaldo P, Rutherford AW, Larkum AW. Early Archean origin of Photosystem II. GEOBIOLOGY 2019; 17:127-150. [PMID: 30411862 PMCID: PMC6492235 DOI: 10.1111/gbi.12322] [Citation(s) in RCA: 59] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/13/2018] [Revised: 10/03/2018] [Accepted: 10/11/2018] [Indexed: 05/09/2023]
Abstract
Photosystem II is a photochemical reaction center that catalyzes the light-driven oxidation of water to molecular oxygen. Water oxidation is the distinctive photochemical reaction that permitted the evolution of oxygenic photosynthesis and the eventual rise of eukaryotes. At what point during the history of life an ancestral photosystem evolved the capacity to oxidize water still remains unknown. Here, we study the evolution of the core reaction center proteins of Photosystem II using sequence and structural comparisons in combination with Bayesian relaxed molecular clocks. Our results indicate that a homodimeric photosystem with sufficient oxidizing power to split water had already appeared in the early Archean about a billion years before the most recent common ancestor of all described Cyanobacteria capable of oxygenic photosynthesis, and well before the diversification of some of the known groups of anoxygenic photosynthetic bacteria. Based on a structural and functional rationale, we hypothesize that this early Archean photosystem was capable of water oxidation to oxygen and had already evolved protection mechanisms against the formation of reactive oxygen species. This would place primordial forms of oxygenic photosynthesis at a very early stage in the evolutionary history of life.
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Affiliation(s)
- Tanai Cardona
- Department of Life SciencesImperial College LondonLondonUK
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7
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Takegawa Y, Nakamura M, Nakamura S, Noguchi T, Sellés J, Rutherford AW, Boussac A, Sugiura M. New insights on Chl D1 function in Photosystem II from site-directed mutants of D1/T179 in Thermosynechococcus elongatus. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2019; 1860:297-309. [PMID: 30703365 DOI: 10.1016/j.bbabio.2019.01.008] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/03/2018] [Revised: 12/17/2018] [Accepted: 01/26/2019] [Indexed: 01/16/2023]
Abstract
The monomeric chlorophyll, ChlD1, which is located between the PD1PD2 chlorophyll pair and the pheophytin, PheoD1, is the longest wavelength chlorophyll in the heart of Photosystem II and is thought to be the primary electron donor. Its central Mg2+ is liganded to a water molecule that is H-bonded to D1/T179. Here, two site-directed mutants, D1/T179H and D1/T179V, were made in the thermophilic cyanobacterium, Thermosynechococcus elongatus, and characterized by a range of biophysical techniques. The Mn4CaO5 cluster in the water-splitting site is fully active in both mutants. Changes in thermoluminescence indicate that i) radiative recombination occurs via the repopulation of *ChlD1 itself; ii) non-radiative charge recombination reactions appeared to be faster in the T179H-PSII; and iii) the properties of PD1PD2 were unaffected by this mutation, and consequently iv) the immediate precursor state of the radiative excited state is the ChlD1+PheoD1- radical pair. Chlorophyll bleaching due to high intensity illumination correlated with the amount of 1O2 generated. Comparison of the bleaching spectra with the electrochromic shifts attributed to ChlD1 upon QA- formation, indicates that in the T179H-PSII and in the WT*3-PSII, the ChlD1 itself is the chlorophyll that is first damaged by 1O2, whereas in the T179V-PSII a more red chlorophyll is damaged, the identity of which is discussed. Thus, ChlD1 appears to be one of the primary damage site in recombination-mediated photoinhibition. Finally, changes in the absorption of ChlD1 very likely contribute to the well-known electrochromic shifts observed at ~430 nm during the S-state cycle.
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Affiliation(s)
- Yuki Takegawa
- Graduate School of Science and Technology, Ehime University, Bunkyo-cho, Matsuyama, Ehime 790-8577, Japan
| | - Makoto Nakamura
- Graduate School of Science and Technology, Ehime University, Bunkyo-cho, Matsuyama, Ehime 790-8577, Japan
| | - Shin Nakamura
- Division of Material Science, Graduate School of Science, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, 464-8602, Japan
| | - Takumi Noguchi
- Division of Material Science, Graduate School of Science, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, 464-8602, Japan
| | - Julien Sellés
- Institut de Biologie Physico-Chimique, UMR CNRS 7141 and Sorbonne Université, 13 rue Pierre et Marie Curie, 75005 Paris, France
| | | | - Alain Boussac
- I(2)BC, UMR CNRS 9198, CEA Saclay, 91191 Gif-sur-Yvette, France.
| | - Miwa Sugiura
- Graduate School of Science and Technology, Ehime University, Bunkyo-cho, Matsuyama, Ehime 790-8577, Japan; Proteo-Science Research Center, Ehime University, Bunkyo-cho, Matsuyama, Ehime 790-8577, Japan.
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Nürnberg DJ, Morton J, Santabarbara S, Telfer A, Joliot P, Antonaru LA, Ruban AV, Cardona T, Krausz E, Boussac A, Fantuzzi A, Rutherford AW. Photochemistry beyond the red limit in chlorophyll f-containing photosystems. Science 2018; 360:1210-1213. [PMID: 29903971 DOI: 10.1126/science.aar8313] [Citation(s) in RCA: 137] [Impact Index Per Article: 22.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2017] [Accepted: 04/18/2018] [Indexed: 11/02/2022]
Abstract
Photosystems I and II convert solar energy into the chemical energy that powers life. Chlorophyll a photochemistry, using red light (680 to 700 nm), is near universal and is considered to define the energy "red limit" of oxygenic photosynthesis. We present biophysical studies on the photosystems from a cyanobacterium grown in far-red light (750 nm). The few long-wavelength chlorophylls present are well resolved from each other and from the majority pigment, chlorophyll a. Charge separation in photosystem I and II uses chlorophyll f at 745 nm and chlorophyll f (or d) at 727 nm, respectively. Each photosystem has a few even longer-wavelength chlorophylls f that collect light and pass excitation energy uphill to the photochemically active pigments. These photosystems function beyond the red limit using far-red pigments in only a few key positions.
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Affiliation(s)
| | | | - Stefano Santabarbara
- Istituto di Biofisica, Consiglio Nazionale delle Ricerche, via Celoria 26, 20133 Milano, Italy
| | - Alison Telfer
- Department of Life Sciences, Imperial College, London SW7 2AZ, UK
| | - Pierre Joliot
- Institut de Biologie Physico-Chimique, Unité Mixte de Recherche 7141 Centre National de la Recherche Scientifique-Université Pierre et Marie Curie, 13 Rue Pierre et Marie Curie, 75005 Paris, France
| | - Laura A Antonaru
- Department of Life Sciences, Imperial College, London SW7 2AZ, UK
| | - Alexander V Ruban
- School of Biological and Chemical Sciences, Queen Mary University of London, London E1 4NS, UK
| | - Tanai Cardona
- Department of Life Sciences, Imperial College, London SW7 2AZ, UK
| | - Elmars Krausz
- Istituto di Biofisica, Consiglio Nazionale delle Ricerche, via Celoria 26, 20133 Milano, Italy
| | - Alain Boussac
- Institut de Biologie Intégrative de la Cellule, UMR 9198, Bât 532, CEA Saclay, 91191 Gif-sur-Yvette, France
| | - Andrea Fantuzzi
- Department of Life Sciences, Imperial College, London SW7 2AZ, UK.
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Kaminskaya OP, Shuvalov VA. Analysis of the transformation effect in cytochrome b559 of photosystem II in terms of the model of the heme-quinone redox interaction. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2018; 1859:1161-1172. [PMID: 32314739 DOI: 10.1016/j.bbabio.2018.07.010] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/12/2018] [Revised: 07/12/2018] [Accepted: 07/24/2018] [Indexed: 10/28/2022]
Abstract
Transformation of three-component redox pattern of cytochrome (Cyt) b559 in PS II membrane fragments upon various treatments is manifested in decrease of the relative content (R) of the high potential (HP) redox form of Cyt b559 and concomitant increase in the fractions of the two lower potential forms. Redox titration of Cyt b559 in different types of PS II membrane preparations was performed and revealed that (1) alteration of redox titration curve of Cyt b559 upon treatment of a sample is not specific to the type of treatment; (2) each value of RHP defines the individual shape of the redox titration curve; (3) population of Cyt b559 may exist in several stable forms with multicomponent redox pattern: three types of three-component redox pattern and one type of two-component redox pattern as well as in the form with a single Em; (4) transformation of Cyt b559 proceeds as successive conversion between the stable forms with multicomponent redox pattern; (5) upon harsh treatments, Cyt b559 abruptly converts into the state with a single Em which value is intermediate between the Em values of the two lower potential forms. Analysis of the data using the model of Cyt b559-quinone redox interaction revealed that diminution of RHP in a range from 80 to 10% reflects a shift in redox equilibrium between the heme group of Cyt b559 and the interacting quinone, due to a gradual decrease of 90 mV in Em of the heme group at the virtually unchanged Em of the quinone component.
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Affiliation(s)
- Olga P Kaminskaya
- Institute of Basic Biological Problems, Russian Academy of Sciences, Pushchino, Moscow Region 142290, Russia.
| | - Vladimir A Shuvalov
- Institute of Basic Biological Problems, Russian Academy of Sciences, Pushchino, Moscow Region 142290, Russia
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10
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Ahmadova N, Mamedov F. Formation of tyrosine radicals in photosystem II under far-red illumination. PHOTOSYNTHESIS RESEARCH 2018; 136:93-106. [PMID: 28924898 PMCID: PMC5851703 DOI: 10.1007/s11120-017-0442-3] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/08/2017] [Accepted: 09/05/2017] [Indexed: 05/27/2023]
Abstract
Photosystem II (PS II) contains two redox-active tyrosine residues on the donor side at symmetrical positions to the primary donor, P680. TyrZ, part of the water-oxidizing complex, is a preferential fast electron donor while TyrD is a slow auxiliary donor to P680+. We used PS II membranes from spinach which were depleted of the water oxidation complex (Mn-depleted PS II) to study electron donation from both tyrosines by time-resolved EPR spectroscopy under visible and far-red continuous light and laser flash illumination. Our results show that under both illumination regimes, oxidation of TyrD occurs via equilibrium with TyrZ• at pH 4.7 and 6.3. At pH 8.5 direct TyrD oxidation by P680+ occurs in the majority of the PS II centers. Under continuous far-red light illumination these reactions were less effective but still possible. Different photochemical steps were considered to explain the far-red light-induced electron donation from tyrosines and localization of the primary electron hole (P680+) on the ChlD1 in Mn-depleted PS II after the far-red light-induced charge separation at room temperature is suggested.
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Affiliation(s)
- Nigar Ahmadova
- Molecular Biomimetics, Department of Chemistry - Ångström Laboratory, Uppsala University, Box 523, 751 20, Uppsala, Sweden
| | - Fikret Mamedov
- Molecular Biomimetics, Department of Chemistry - Ångström Laboratory, Uppsala University, Box 523, 751 20, Uppsala, Sweden.
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Narzi D, Coccia E, Manzoli M, Guidoni L. Impact of molecular flexibility on the site energy shift of chlorophylls in Photosystem II. Biophys Chem 2017; 229:93-98. [DOI: 10.1016/j.bpc.2017.06.013] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2017] [Revised: 06/26/2017] [Accepted: 06/26/2017] [Indexed: 01/31/2023]
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12
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Yanykin DV, Khorobrykh AA, Terentyev VV, Klimov VV. Two pathways of photoproduction of organic hydroperoxides on the donor side of photosystem 2 in subchloroplast membrane fragments. PHOTOSYNTHESIS RESEARCH 2017; 133:129-138. [PMID: 28349346 DOI: 10.1007/s11120-017-0373-z] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/17/2016] [Accepted: 03/20/2017] [Indexed: 06/06/2023]
Abstract
Earlier the catalase-insensitive formation of organic hydroperoxides (via the interaction of organic radicals produced due to redox activity of P680+· (or TyrZ·) with molecular oxygen) has been found in Mn-depleted PS2 preparations (apo-WOC-PS2) by Khorobrykh et al. (Biochemistry 50:10658-10665, 2011). The present work describes a second pathway of the photoproduction of organic peroxides on the donor side of PS2. It was shown that illumination of CaCl2-treated PS2 membranes (deprived of the PS2 extrinsic proteins without removal of the Mn-containing water-oxidizing complex) (CaCl2-PS2) led to the photoproduction of highly lipophilic organic hydroperoxides (LP-OOH) (in amount corresponding to 1.5 LP-OOH per one reaction center of PS2) which significantly increased upon the addition of exogenous electron acceptor potassium ferricyanide (to 4.2 LP-OOH per one reaction center). Addition of catalase (200 U/ml) before illumination inhibited ferricyanide-induced photoproduction of hydroperoxides while no effect was obtained by adding catalase after illumination or by adding inactivated catalase before illumination. The hydroperoxide photoproduction was inhibited by the addition of exogenous electron donor for PS2, diphenylcarbazide or diuron (inhibitor of the electron transfer in PS2). The addition of exogenous hydrogen peroxide to the CaCl2-PS2 led to the production of highly lipophilic organic hydroperoxides in the dark (3.2 LP-OOH per one reaction center). We suggest that the photoproduction of highly lipophilic organic hydroperoxides in CaCl2-PS2 preparations occurs via redox activity of H2O2 produced on the donor side of PS2.
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Affiliation(s)
- D V Yanykin
- Institute of Basic Biological Problems, Russian Academy of Sciences, Pushchino, Moscow Region, Russia, 142290.
| | - A A Khorobrykh
- Institute of Basic Biological Problems, Russian Academy of Sciences, Pushchino, Moscow Region, Russia, 142290
| | - V V Terentyev
- Institute of Basic Biological Problems, Russian Academy of Sciences, Pushchino, Moscow Region, Russia, 142290
| | - V V Klimov
- Institute of Basic Biological Problems, Russian Academy of Sciences, Pushchino, Moscow Region, Russia, 142290
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Jia Y, Shi Y, Wang P, Zhang JP. Triplet excitation dynamics of β -carotene studied in three solvents by ns flash photolysis spectroscopy. CHINESE CHEM LETT 2017. [DOI: 10.1016/j.cclet.2016.05.032] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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14
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Stamatakis K, Papageorgiou GC. Effects of exogenous β-carotene, a chemical scavenger of singlet oxygen, on the millisecond rise of chlorophyll a fluorescence of cyanobacterium Synechococcus sp. PCC 7942. PHOTOSYNTHESIS RESEARCH 2016; 130:317-324. [PMID: 27034066 DOI: 10.1007/s11120-016-0255-9] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/03/2016] [Accepted: 03/23/2016] [Indexed: 06/05/2023]
Abstract
Singlet-excited oxygen (1O 2* ) has been recognized as the most destructive member of the reactive oxygen species (ROS) which are formed during oxygenic photosynthesis by plants, algae, and cyanobacteria. ROS and 1O 2* are known to damage protein and phospholipid structures and to impair photosynthetic electron transport and de novo protein synthesis. Partial protection is afforded to photosynthetic organism by the β-carotene (β-Car) molecules which accompany chlorophyll (Chl) a in the pigment-protein complexes of Photosystem II (PS II). In this paper, we studied the effects of exogenously added β-Car on the initial kinetic rise of Chl a fluorescence (10-1000 μs, the OJ segment) from the unicellular cyanobacterium Synechococcus sp. PCC7942. We show that the added β-Car enhances Chl a fluorescence when it is excited at an intensity of 3000 μmol photons m-2 s-1 but not when excited at 1000 μmol photons m-2 s-1. Since β-Car is an efficient scavenger of 1O 2* , as well as a quencher of 3Chl a * (precursor of 1O 2* ), both of which are more abundant at higher excitations, we assume that the higher Chl a fluorescence in its presence signifies a protective effect against photo-oxidative damages of Chl proteins. The protective effect of added β-Car is not observed in O2-depleted cell suspensions. Lastly, in contrast to β-Car, a water-insoluble molecule, a water-soluble scavenger of 1O 2* , histidine, provides no protection to Chl proteins during the same time period (10-1000 μs).
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Affiliation(s)
- Kostas Stamatakis
- Institute of Biosciences and Applications, National Center of Scientific Research "Demokritos", 15310, Athens, Greece
| | - George C Papageorgiou
- Institute of Biosciences and Applications, National Center of Scientific Research "Demokritos", 15310, Athens, Greece.
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15
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Khorobrykh AA, Klimov VV. Involvement of molecular oxygen in the donor-side photoinhibition of Mn-depleted photosystem II membranes. PHOTOSYNTHESIS RESEARCH 2015; 126:417-425. [PMID: 25862644 DOI: 10.1007/s11120-015-0135-8] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/29/2014] [Accepted: 03/26/2015] [Indexed: 06/04/2023]
Abstract
It has been shown by Khorobrykh et al. (Biochemistry (Moscow) 67:683-688, 2002); Yanykin et al. (Biochim Biophys Acta 1797:516-523, 2010); Khorobrykh et al. (Biochemistry 50:10658-10665, 2011) that Mn-depleted photosystem II (PSII) membrane fragments are characterized by an enhanced oxygen photoconsumption on the donor side of PSII which is accompanied with hydroperoxide formation and it was suggested that the events are related to the oxidative photoinhibition of PSII. Experimental confirmation of this suggestion is presented in this work. The degree of photoinhibition was determined by the loss of the capability of exogenous electron donors (Mn(2+) or sodium ascorbate) to the reactivation of electron transport [measured by the light-induced changes of chlorophyll fluorescence yield (∆F)] in Mn-depleted PSII membranes. The transition from anaerobic conditions to aerobic ones significantly activated photoinhibition of Mn-depleted PSII membranes both in the absence and in the presence of exogenous electron acceptor, ferricyanide. The photoinhibition of Mn-depleted PSII membranes was suppressed upon the addition of exogenous electron donors (Mn(2+), diphenylcarbazide, and ferrocyanide). The addition of superoxide dismutase did not affect the photoinhibition of Mn-depleted PSII membranes. It is concluded that the interaction of molecular oxygen (rather than superoxide anion radical formed on the acceptor side of PSII) with the oxidized components of the donor side of PSII reflects the involvement of O2 in the donor-side photoinhibition of Mn-depleted PSII membranes.
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Affiliation(s)
- A A Khorobrykh
- Institute of Basic Biological Problems, Russian Academy of Sciences, Pushchino, Moscow Region, 142290, Russia.
| | - V V Klimov
- Institute of Basic Biological Problems, Russian Academy of Sciences, Pushchino, Moscow Region, 142290, Russia
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16
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Kaminskaya OP, Shuvalov VA. Towards an understanding of redox heterogeneity of the photosystem II cytochrome b559 in the native membrane. EUROPEAN BIOPHYSICS JOURNAL: EBJ 2015; 45:129-38. [DOI: 10.1007/s00249-015-1082-1] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/17/2015] [Revised: 09/07/2015] [Accepted: 09/16/2015] [Indexed: 11/29/2022]
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17
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Li L, Hu F, Chang YQ, Zhou Y, Wang P, Zhang JP. Triplet excitation dynamics of two keto-carotenoids in n-hexane and in methanol as studied by ns flash photolysis spectroscopy. Chem Phys Lett 2015. [DOI: 10.1016/j.cplett.2015.05.022] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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18
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Laisk A, Eichelmann H, Oja V. Oxidation of plastohydroquinone by photosystem II and by dioxygen in leaves. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2015; 1847:565-75. [PMID: 25800682 DOI: 10.1016/j.bbabio.2015.03.003] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 11/17/2014] [Revised: 02/16/2015] [Accepted: 03/15/2015] [Indexed: 10/23/2022]
Abstract
In sunflower leaves linear electron flow LEF=4O2 evolution rate was measured at 20 ppm O2 in N2. PSII charge separation rate CSRII=aII∙PAD∙(Fm-F)/Fm, where aII is excitation partitioning to PSII, PAD is photon absorption density, Fm and F are maximum and actual fluorescence yields. Under 630 nm LED+720 nm far-red light (FRL), LEF was equal to CSRII with aII=0.51 to 0.58. After FRL was turned off, plastoquinol (PQH2) accumulated, but LEF decreased more than accountable by F increase, indicating PQH2-oxidizing cyclic electron flow in PSII (CEFII). CEFII was faster under conditions requiring more ATP, consistent with CEFII being coupled with proton translocation. We propose that PQH2 bound to the QC site is oxidized, one e- moving to P680+, the other e- to Cyt b559. From Cyt b559 the e- reduces QB- at the QB site, forming PQH2. About 10-15% electrons may cycle, causing misses in the period-4 flash O2 evolution and lower quantum yield of photosynthesis under stress. We also measured concentration dependence of PQH2 oxidation by dioxygen, as indicated by post-illumination decrease of Chl fluorescence yield. After light was turned off, F rapidly decreased from Fm to 0.2 Fv, but further decrease to F0 was slow and O2 concentration dependent. The rate constant of PQH2 oxidation, determined from this slow phase, was 0.054 s(-1) at 270 μM (21%) O2, decreasing with Km(O2) of 60 μM (4.6%) O2. This eliminates the interference of O2 in the measurements of CEFII.
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Affiliation(s)
- Agu Laisk
- Tartu Ülikooli Tehnoloogia Instituut, Nooruse tn. 1, Tartu 50411, Estonia.
| | - Hillar Eichelmann
- Tartu Ülikooli Tehnoloogia Instituut, Nooruse tn. 1, Tartu 50411, Estonia
| | - Vello Oja
- Tartu Ülikooli Tehnoloogia Instituut, Nooruse tn. 1, Tartu 50411, Estonia
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Caffarri S, Tibiletti T, Jennings RC, Santabarbara S. A comparison between plant photosystem I and photosystem II architecture and functioning. Curr Protein Pept Sci 2015; 15:296-331. [PMID: 24678674 PMCID: PMC4030627 DOI: 10.2174/1389203715666140327102218] [Citation(s) in RCA: 131] [Impact Index Per Article: 14.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2013] [Revised: 11/22/2013] [Accepted: 03/16/2014] [Indexed: 01/31/2023]
Abstract
Oxygenic photosynthesis is indispensable both for the development and maintenance of life on earth by converting
light energy into chemical energy and by producing molecular oxygen and consuming carbon dioxide. This latter
process has been responsible for reducing the CO2 from its very high levels in the primitive atmosphere to the present low
levels and thus reducing global temperatures to levels conducive to the development of life. Photosystem I and photosystem
II are the two multi-protein complexes that contain the pigments necessary to harvest photons and use light energy to
catalyse the primary photosynthetic endergonic reactions producing high energy compounds. Both photosystems are
highly organised membrane supercomplexes composed of a core complex, containing the reaction centre where electron
transport is initiated, and of a peripheral antenna system, which is important for light harvesting and photosynthetic activity
regulation. If on the one hand both the chemical reactions catalysed by the two photosystems and their detailed structure
are different, on the other hand they share many similarities. In this review we discuss and compare various aspects of
the organisation, functioning and regulation of plant photosystems by comparing them for similarities and differences as
obtained by structural, biochemical and spectroscopic investigations.
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Affiliation(s)
| | | | | | - Stefano Santabarbara
- Laboratoire de Génétique et de Biophysique des Plantes (LGBP), Aix-Marseille Université, Faculté des Sciences de Luminy, 163 Avenue de Luminy, 13009, Marseille, France.
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20
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Mokvist F, Sjöholm J, Mamedov F, Styring S. The Photochemistry in Photosystem II at 5 K Is Different in Visible and Far-Red Light. Biochemistry 2014; 53:4228-38. [DOI: 10.1021/bi5006392] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Fredrik Mokvist
- Molecular Biomimetics, Department
of Chemistry-Ångström, Uppsala University, Ångström Laboratory, P.O. Box 523, S-751 20 Uppsala, Sweden
| | - Johannes Sjöholm
- Molecular Biomimetics, Department
of Chemistry-Ångström, Uppsala University, Ångström Laboratory, P.O. Box 523, S-751 20 Uppsala, Sweden
| | - Fikret Mamedov
- Molecular Biomimetics, Department
of Chemistry-Ångström, Uppsala University, Ångström Laboratory, P.O. Box 523, S-751 20 Uppsala, Sweden
| | - Stenbjörn Styring
- Molecular Biomimetics, Department
of Chemistry-Ångström, Uppsala University, Ångström Laboratory, P.O. Box 523, S-751 20 Uppsala, Sweden
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21
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Yanykin DV, Khorobrykh AA, Zastrizhnaya OM, Klimov VV. Interaction of molecular oxygen with the donor side of photosystem II after destruction of the water-oxidizing complex. BIOCHEMISTRY (MOSCOW) 2014; 79:205-12. [PMID: 24821446 DOI: 10.1134/s0006297914030055] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Photosystem II (PSII) is a pigment-protein complex of thylakoid membrane of higher plants, algae, and cyanobacteria where light energy is used for oxidation of water and reduction of plastoquinone. Light-dependent reactions (generation of excited states of pigments, electron transfer, water oxidation) taking place in PSII can lead to the formation of reactive oxygen species. In this review attention is focused on the problem of interaction of molecular oxygen with the donor site of PSII, where after the removal of manganese from the water-oxidizing complex illumination induces formation of long-lived states (P680(+•) and TyrZ(•)) capable of oxidizing surrounding organic molecules to form radicals.
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Affiliation(s)
- D V Yanykin
- Institute of Basic Biological Problems, Russian Academy of Sciences, Pushchino, Moscow Region, 142290, Russia.
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22
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Shinopoulos KE, Yu J, Nixon PJ, Brudvig GW. Using site-directed mutagenesis to probe the role of the D2 carotenoid in the secondary electron-transfer pathway of photosystem II. PHOTOSYNTHESIS RESEARCH 2014; 120:141-52. [PMID: 23334888 PMCID: PMC3961632 DOI: 10.1007/s11120-013-9793-6] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/18/2012] [Accepted: 01/02/2013] [Indexed: 05/07/2023]
Abstract
Secondary electron transfer in photosystem II (PSII), which occurs when water oxidation is inhibited, involves redox-active carotenoids (Car), as well as chlorophylls (Chl), and cytochrome b 559 (Cyt b 559), and is believed to play a role in photoprotection. CarD2 may be the initial point of secondary electron transfer because it is the closest cofactor to both P680, the initial oxidant, and to Cyt b 559, the terminal secondary electron donor within PSII. In order to characterize the role of CarD2 and to determine the effects of perturbing CarD2 on both the electron-transfer events and on the identity of the redox-active cofactors, it is necessary to vary the properties of CarD2 selectively without affecting the ten other Car per PSII. To this end, site-directed mutations around the binding pocket of CarD2 (D2-G47W, D2-G47F, and D2-T50F) have been generated in Synechocystis sp. PCC 6803. Characterization by near-IR and EPR spectroscopy provides the first experimental evidence that CarD2 is one of the redox-active carotenoids in PSII. There is a specific perturbation of the Car(∙+) near-IR spectrum in all three mutated PSII samples, allowing the assignment of the spectral signature of Car D2 (∙+) ; Car D2 (∙+) exhibits a near-IR peak at 980 nm and is the predominant secondary donor oxidized in a charge separation at low temperature in ferricyanide-treated wild-type PSII. The yield of secondary donor radicals is substantially decreased in PSII complexes isolated from each mutant. In addition, the kinetics of radical formation are altered in the mutated PSII samples. These results are consistent with oxidation of CarD2 being the initial step in secondary electron transfer. Furthermore, normal light levels during mutant cell growth perturb the shape of the Chl(∙+) near-IR absorption peak and generate a dark-stable radical observable in the EPR spectra, indicating a higher susceptibility to photodamage further linking the secondary electron-transfer pathway to photoprotection.
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Affiliation(s)
| | - Jianfeng Yu
- Division of Molecular Biosciences, Sir Ernst Chain Building – Wolfson Laboratories, Imperial College London, S. Kensington campus, London, SW7 2AY UK
| | - Peter J. Nixon
- Division of Molecular Biosciences, Sir Ernst Chain Building – Wolfson Laboratories, Imperial College London, S. Kensington campus, London, SW7 2AY UK
| | - Gary W. Brudvig
- Department of Chemistry, Yale University, New Haven, CT 06520-8107 USA
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23
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Pospíšil P. The Role of Metals in Production and Scavenging of Reactive Oxygen Species in Photosystem II. ACTA ACUST UNITED AC 2014; 55:1224-32. [DOI: 10.1093/pcp/pcu053] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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24
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Yanykin DV, Khorobrykh AA, Khorobrykh SA, Pshybytko NL, Klimov VV. Flash-induced consumption of molecular oxygen on the donor side of photosystem II in Mn-depleted subchloroplast membrane fragments: specific effects of manganese and calcium ions. PHOTOSYNTHESIS RESEARCH 2013; 117:367-374. [PMID: 23756831 DOI: 10.1007/s11120-013-9868-4] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/04/2013] [Accepted: 05/30/2013] [Indexed: 06/02/2023]
Abstract
It has been shown that removal of manganese from the water-oxidizing complex (WOC) of photosystem II (PSII) leads to flash-induced oxygen consumption (FIOC) which is activated by low concentration of Mn(2+) (Yanykin et al., Biochim Biophys Acta 1797:516-523, 2010). In the present work, we examined the effect of transition and non-transition divalent metal ions on FIOC in Mn-depleted PSII (apo-WOC-PSII) preparations. It was shown that only Mn(2+) ions are able to activate FIOC while other transition metal ions (Fe(2+), V(2+) and Cr(2+)) capable of electron donation to the apo-WOC-PSII suppressed the photoconsumption of O2. Co(2+) ions with a high redox potential (E (0) for Co(2+)/Co(3+) is 1.8 V) showed no effect. Non-transition metal ions Ca(2+) by Mg(2+) did not stimulate FIOC. However, Ca(2+) (in contrast to Mg(2+)) showed an additional activation effect in the presence of exogenic Mn(2+). The Ca(2+) effect depended on the concentration of both Mn(2+) and Ca(2+). The Ca effect was only observed when: (1) the activation of FIOC induced by Mn(2+) did not reach its maximum, (2) the concentration of Ca(2+) did not exceed 40 μM; at higher concentrations Ca(2+) inhibited the Mn(2+)-activated O2 photoconsumption. Replacement of Ca(2+) by Mg(2+) led to a suppression of Mn(2+)-activated O2 photoconsumption; while, addition of Ca(2+) resulted in elimination of the Mg(2+) inhibitory effect and activation of FIOC. Thus, only Mn(2+) and Ca(2+) (which are constituents of the WOC) have specific effects of activation of FIOC in apo-WOC-PSII preparations. Possible reactions involving Mn(2+) and Ca(2+) which could lead to the activation of FIOC in the apo-WOC-PSII are discussed.
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Affiliation(s)
- D V Yanykin
- Institute of Basic Biological Problems, Russian Academy of Sciences, Pushchino, Moscow Region, 142290, Russia
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25
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Pagliano C, Saracco G, Barber J. Structural, functional and auxiliary proteins of photosystem II. PHOTOSYNTHESIS RESEARCH 2013; 116:167-88. [PMID: 23417641 DOI: 10.1007/s11120-013-9803-8] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/22/2012] [Accepted: 02/07/2013] [Indexed: 05/06/2023]
Abstract
Photosystem II (PSII) is the water-splitting enzyme complex of photosynthesis and consists of a large number of protein subunits. Most of these proteins have been structurally and functionally characterized, although there are differences between PSII of plants, algae and cyanobacteria. Here we catalogue all known PSII proteins giving a brief description, where possible of their genetic origin, physical properties, structural relationships and functions. We have also included details of auxiliary proteins known at present to be involved in the in vivo assembly, maintenance and turnover of PSII and which transiently bind to the reaction centre core complex. Finally, we briefly give details of the proteins which form the outer light-harvesting systems of PSII in different types of organisms.
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Affiliation(s)
- Cristina Pagliano
- Applied Science and Technology Department-BioSolar Lab, Politecnico di Torino, Viale T. Michel 5, 15121, Torino, Alessandria, Italy,
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26
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Kaminskaya OP, Shuvalov VA. Biphasic reduction of cytochrome b559 by plastoquinol in photosystem II membrane fragments: evidence for two types of cytochrome b559/plastoquinone redox equilibria. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2013; 1827:471-83. [PMID: 23357332 DOI: 10.1016/j.bbabio.2013.01.007] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/19/2012] [Revised: 01/14/2013] [Accepted: 01/16/2013] [Indexed: 10/27/2022]
Abstract
In photosystem II membrane fragments with oxidized cytochrome (Cyt) b559 reduction of Cyt b559 by plastoquinol formed in the membrane pool under illumination and by exogenous decylplastoquinol added in the dark was studied. Reduction of oxidized Cyt b559 by plastoquinols proceeds biphasically comprising a fast component with a rate constant higher than (10s)(-1), named phase I, followed by a slower dark reaction with a rate constant of (2.7min)(-1) at pH6.5, termed phase II. The extents of both components of Cyt b559 reduction increased with increasing concentrations of the quinols, with that, maximally a half of oxidized Cyt b559 can be photoreduced or chemically reduced in phase I at pH6.5. The photosystem II herbicide dinoseb but not 3-(3,4-dichlorophenyl)-1,1-dimethylurea (DCMU) competed with the quinol reductant in phase I. The results reveal that the two components of the Cyt b559 redox reaction reflect two redox equilibria attaining in different time domains. One-electron redox equilibrium between oxidized Cyt b559 and the photosystem II-bound plastoquinol is established in phase I of Cyt b559 reduction. Phase II is attributed to equilibration of Cyt b559 redox forms with the quinone pool. The quinone site involved in phase I of Cyt b559 reduction is considered to be the site regulating the redox potential of Cyt b559 which can accommodate quinone, semiquinone and quinol forms. The properties of this site designated here as QD clearly suggest that it is distinct from the site QC found in the photosystem II crystal structure.
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Affiliation(s)
- Olga P Kaminskaya
- Institute of Basic Biological Problems, Russian Academy of Sciences, Pushchino, Moscow Region 142290, Russia.
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27
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Pillai S, Ravensbergen J, Antoniuk-Pablant A, Sherman BD, van Grondelle R, Frese RN, Moore TA, Gust D, Moore AL, Kennis JTM. Carotenoids as electron or excited-state energy donors in artificial photosynthesis: an ultrafast investigation of a carotenoporphyrin and a carotenofullerene dyad. Phys Chem Chem Phys 2013; 15:4775-84. [DOI: 10.1039/c3cp50364j] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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28
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Feyziyev Y, Deák Z, Styring S, Bernát G. Electron transfer from Cyt b(559) and tyrosine-D to the S2 and S3 states of the water oxidizing complex in photosystem II at cryogenic temperatures. J Bioenerg Biomembr 2012; 45:111-20. [PMID: 23104119 DOI: 10.1007/s10863-012-9482-8] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2012] [Accepted: 08/06/2012] [Indexed: 11/30/2022]
Abstract
The Mn(4)CaO(5) cluster of photosystem II (PSII) catalyzes the oxidation of water to molecular oxygen through the light-driven redox S-cycle. The water oxidizing complex (WOC) forms a triad with Tyrosine(Z) and P(680), which mediates electrons from water towards the acceptor side of PSII. Under certain conditions two other redox-active components, Tyrosine(D) (Y(D)) and Cytochrome b(559) (Cyt b(559)) can also interact with the S-states. In the present work we investigate the electron transfer from Cyt b(559) and Y(D) to the S(2) and S(3) states at 195 K. First, Y(D)(•) and Cyt b(559) were chemically reduced. The S(2) and S(3) states were then achieved by application of one or two laser flashes, respectively, on samples stabilized in the S(1) state. EPR signals of the WOC (the S(2)-state multiline signal, ML-S(2)), Y(D)(•) and oxidized Cyt b(559) were simultaneously detected during a prolonged dark incubation at 195 K. During 163 days of incubation a large fraction of the S(2) population decayed to S(1) in the S(2) samples by following a single exponential decay. Differently, S(3) samples showed an initial increase in the ML-S(2) intensity (due to S(3) to S(2) conversion) and a subsequent slow decay due to S(2) to S(1) conversion. In both cases, only a minor oxidation of Y(D) was observed. In contrast, the signal intensity of the oxidized Cyt b(559) showed a two-fold increase in both the S(2) and S(3) samples. The electron donation from Cyt b(559) was much more efficient to the S(2) state than to the S(3) state.
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Affiliation(s)
- Yashar Feyziyev
- Institute of Botany, 40 Patamdar Shosse, AZ-1073 Baku, Azerbaijan
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29
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Khorobrykh SA, Khorobrykh AA, Yanykin DV, Ivanov BN, Klimov VV, Mano J. Photoproduction of Catalase-Insensitive Peroxides on the Donor Side of Manganese-Depleted Photosystem II: Evidence with a Specific Fluorescent Probe. Biochemistry 2011; 50:10658-65. [DOI: 10.1021/bi200945v] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Affiliation(s)
- Sergey A. Khorobrykh
- Institute
of Basic Biological Problems, Russian Academy of Sciences, Pushchino, Moscow Region 142290, Russia
- Science Research Center, Yamaguchi University, Yoshida 1677-1, Yamaguchi 753-8515, Japan
| | - Andrei A. Khorobrykh
- Institute
of Basic Biological Problems, Russian Academy of Sciences, Pushchino, Moscow Region 142290, Russia
| | - Denis V. Yanykin
- Institute
of Basic Biological Problems, Russian Academy of Sciences, Pushchino, Moscow Region 142290, Russia
| | - Boris N. Ivanov
- Institute
of Basic Biological Problems, Russian Academy of Sciences, Pushchino, Moscow Region 142290, Russia
| | - Vyacheslav V. Klimov
- Institute
of Basic Biological Problems, Russian Academy of Sciences, Pushchino, Moscow Region 142290, Russia
| | - Jun’ichi Mano
- Science Research Center, Yamaguchi University, Yoshida 1677-1, Yamaguchi 753-8515, Japan
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30
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Shinopoulos KE, Brudvig GW. Cytochrome b₅₅₉ and cyclic electron transfer within photosystem II. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2011; 1817:66-75. [PMID: 21864501 DOI: 10.1016/j.bbabio.2011.08.002] [Citation(s) in RCA: 86] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/25/2011] [Revised: 08/06/2011] [Accepted: 08/08/2011] [Indexed: 11/18/2022]
Abstract
Cytochrome b₅₅₉ (Cyt b₅₅₉), β-carotene (Car), and chlorophyll (Chl) cofactors participate in the secondary electron-transfer pathways in photosystem II (PSII), which are believed to protect PSII from photodamage under conditions in which the primary electron-donation pathway leading to water oxidation is inhibited. Among these cofactors, Cyt b₅₅₉ is preferentially photooxidized under conditions in which the primary electron-donation pathway is blocked. When Cyt b₅₅₉ is preoxidized, the photooxidation of several of the 11 Car and 35 Chl molecules present per PSII is observed. In this review, the discovery of the secondary electron donors, their structures and electron-transfer properties, and progress in the characterization of the secondary electron-transfer pathways are discussed. This article is part of a Special Issue entitled: Photosystem II.
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31
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Cardona T, Sedoud A, Cox N, Rutherford AW. Charge separation in photosystem II: a comparative and evolutionary overview. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2011; 1817:26-43. [PMID: 21835158 DOI: 10.1016/j.bbabio.2011.07.012] [Citation(s) in RCA: 243] [Impact Index Per Article: 18.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/29/2011] [Revised: 07/22/2011] [Accepted: 07/23/2011] [Indexed: 10/17/2022]
Abstract
Our current understanding of the PSII reaction centre owes a great deal to comparisons to the simpler and better understood, purple bacterial reaction centre. Here we provide an overview of the similarities with a focus on charge separation and the electron acceptors. We go on to discuss some of the main differences between the two kinds of reaction centres that have been highlighted by the improving knowledge of PSII. We attempt to relate these differences to functional requirements of water splitting. Some are directly associated with that function, e.g. high oxidation potentials, while others are associated with regulation and protection against photodamage. The protective and regulatory functions are associated with the harsh chemistry performed during its normal function but also with requirements of the enzyme while it is undergoing assembly and repair. Key aspects of PSII reaction centre evolution are also addressed. This article is part of a Special Issue entitled: Photosystem II.
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Affiliation(s)
- Tanai Cardona
- Institut de Biologie et Technologies de Saclay, URA 2096 CNRS, CEA Saclay, 91191 Gif-sur-Yvette, France
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Keough JM, Jenson DL, Zuniga AN, Barry BA. Proton coupled electron transfer and redox-active tyrosine Z in the photosynthetic oxygen-evolving complex. J Am Chem Soc 2011; 133:11084-7. [PMID: 21714528 PMCID: PMC3246746 DOI: 10.1021/ja2041139] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Proton coupled electron transfer (PCET) reactions play an essential role in many enzymatic processes. In PCET, redox-active tyrosines may be involved as intermediates when the oxidized phenolic side chain deprotonates. Photosystem II (PSII) is an excellent framework for studying PCET reactions, because it contains two redox-active tyrosines, YD and YZ, with different roles in catalysis. One of the redox-active tyrosines, YZ, is essential for oxygen evolution and is rapidly reduced by the manganese-catalytic site. In this report, we investigate the mechanism of YZ PCET in oxygen-evolving PSII. To isolate YZ(•) reactions, but retain the manganese-calcium cluster, low temperatures were used to block the oxidation of the metal cluster, high microwave powers were used to saturate the YD(•) EPR signal, and YZ(•) decay kinetics were measured with EPR spectroscopy. Analysis of the pH and solvent isotope dependence was performed. The rate of YZ(•) decay exhibited a significant solvent isotope effect, and the rate of recombination and the solvent isotope effect were pH independent from pH 5.0 to 7.5. These results are consistent with a rate-limiting, coupled proton electron transfer (CPET) reaction and are contrasted to results obtained for YD(•) decay kinetics at low pH. This effect may be mediated by an extensive hydrogen-bond network around YZ. These experiments imply that PCET reactions distinguish the two PSII redox-active tyrosines.
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Affiliation(s)
- James M. Keough
- School of Chemistry and Biochemistry and the Petit Institute for Bioengineering and Bioscience, Georgia Institute of Technology, Atlanta, Georgia 30332
| | - David L. Jenson
- School of Chemistry and Biochemistry and the Petit Institute for Bioengineering and Bioscience, Georgia Institute of Technology, Atlanta, Georgia 30332
| | - Ashley N. Zuniga
- School of Chemistry and Biochemistry and the Petit Institute for Bioengineering and Bioscience, Georgia Institute of Technology, Atlanta, Georgia 30332
| | - Bridgette A. Barry
- School of Chemistry and Biochemistry and the Petit Institute for Bioengineering and Bioscience, Georgia Institute of Technology, Atlanta, Georgia 30332
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Enzymatic function of cytochrome b559 in photosystem II. JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY B-BIOLOGY 2011; 104:341-7. [DOI: 10.1016/j.jphotobiol.2011.02.013] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/30/2010] [Revised: 02/10/2011] [Accepted: 02/11/2011] [Indexed: 11/22/2022]
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Sedoud A, Cox N, Sugiura M, Lubitz W, Boussac A, Rutherford AW. Semiquinone–Iron Complex of Photosystem II: EPR Signals Assigned to the Low-Field Edge of the Ground State Doublet of QA•–Fe2+ and QB•–Fe2+. Biochemistry 2011; 50:6012-21. [DOI: 10.1021/bi200313p] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Arezki Sedoud
- iBiTec-S, CNRS URA 2096, CEA Saclay, 91191 Gif-sur-Yvette, France
| | - Nicholas Cox
- MPI für Bioanorganische Chemie, Stiftstrasse 34-36, D-45470 Mülheim an der Ruhr, Germany
| | - Miwa Sugiura
- Cell-Free Science and Technology Research Center, Ehime University, Bunkyo-cho, Matsuyama, Ehime 790-8577, Japan
| | - Wolfgang Lubitz
- MPI für Bioanorganische Chemie, Stiftstrasse 34-36, D-45470 Mülheim an der Ruhr, Germany
| | - Alain Boussac
- iBiTec-S, CNRS URA 2096, CEA Saclay, 91191 Gif-sur-Yvette, France
| | - A. William Rutherford
- iBiTec-S, CNRS URA 2096, CEA Saclay, 91191 Gif-sur-Yvette, France
- Molecular Biosciences, Imperial College, London SW4 2AZ, U.K
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Chen G, Allahverdiyeva Y, Aro EM, Styring S, Mamedov F. Electron paramagnetic resonance study of the electron transfer reactions in photosystem II membrane preparations from Arabidopsis thaliana. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2011; 1807:205-15. [DOI: 10.1016/j.bbabio.2010.10.010] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/01/2010] [Revised: 10/06/2010] [Accepted: 10/08/2010] [Indexed: 10/18/2022]
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Abstract
Carotenoids are one of the most widespread groups of pigments in nature and more than 600 of these have been identified. Beside provitamin A activity, carotenoids are important as antioxidants and protective agents against various diseases. They are isoprenoids with a long polyene chain containing 3 to 15 conjugated double bonds, which determines their absorption spectrum. Cyclization at one or both ends occurs in hydrocarbon carotene, while xanthophylls are formed by the introduction of oxygen. In addition, modifications involving chain elongation, isomerization, or degradation are also found. The composition of carotenoids in food may vary depending upon production practices, post-harvest handling, processing, and storage. In higher plants they are synthesized in the plastid. Both mevalonate dependent and independent pathway for the formation of isopentenyl diphosphate are known. Isopentenyl diphosphate undergoes a series of addition and condensation reactions to form phytoene, which gets converted to lycopene. Cyclization of lycopene either leads to the formation of β-carotene and its derivative xanthophylls, β-cryptoxanthin, zeaxanthin, antheraxanthin, and violaxanthin or α-carotene and lutein. Even though most of the carotenoid biosynthetic genes have been cloned and identified, some aspects of carotenoid formation and manipulation in higher plants especially remain poorly understood. In order to enhance the carotenoid content of crop plants to a level that will be required for the prevention of diseases, there is a need for research in both the basic and the applied aspects.
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Affiliation(s)
- K K Namitha
- Human Resource Development, Central Food Technological Research Institute (CSIR), Mysore, India
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Havelius KGV, Su JH, Han G, Mamedov F, Ho FM, Styring S. The formation of the split EPR signal from the S(3) state of Photosystem II does not involve primary charge separation. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2010; 1807:11-21. [PMID: 20863810 DOI: 10.1016/j.bbabio.2010.09.006] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/27/2010] [Revised: 09/14/2010] [Accepted: 09/15/2010] [Indexed: 11/16/2022]
Abstract
Metalloradical EPR signals have been found in intact Photosystem II at cryogenic temperatures. They reflect the light-driven formation of the tyrosine Z radical (Y(Z)) in magnetic interaction with the CaMn(4) cluster in a particular S state. These so-called split EPR signals, induced at cryogenic temperatures, provide means to study the otherwise transient Y(Z) and to probe the S states with EPR spectroscopy. In the S(0) and S(1) states, the respective split signals are induced by illumination of the sample in the visible light range only. In the S(3) state the split EPR signal is induced irrespective of illumination wavelength within the entire 415-900nm range (visible and near-IR region) [Su, J. H., Havelius, K. G. V., Ho, F. M., Han, G., Mamedov, F., and Styring, S. (2007) Biochemistry 46, 10703-10712]. An important question is whether a single mechanism can explain the induction of the Split S(3) signal across the entire wavelength range or whether wavelength-dependent mechanisms are required. In this paper we confirm that the Y(Z) radical formation in the S(1) state, reflected in the Split S(1) signal, is driven by P680-centered charge separation. The situation in the S(3) state is different. In Photosystem II centers with pre-reduced quinone A (Q(A)), where the P680-centered charge separation is blocked, the Split S(3) EPR signal could still be induced in the majority of the Photosystem II centers using both visible and NIR (830nm) light. This shows that P680-centered charge separation is not involved. The amount of oxidized electron donors and reduced electron acceptors (Q(A)(-)) was well correlated after visible light illumination at cryogenic temperatures in the S(1) state. This was not the case in the S(3) state, where the Split S(3) EPR signal was formed in the majority of the centers in a pathway other than P680-centered charge separation. Instead, we propose that one mechanism exists over the entire wavelength interval to drive the formation of the Split S(3) signal. The origin for this, probably involving excitation of one of the Mn ions in the CaMn(4) cluster in Photosystem II, is discussed.
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Affiliation(s)
- Kajsa G V Havelius
- Molecular Biomimetrics, Department of Photochemistry and Molecular Sciences, Uppsala University, The Angström Laboratory, Uppsala, Sweden
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Sugiura M, Harada S, Manabe T, Hayashi H, Kashino Y, Boussac A. Psb30 contributes to structurally stabilise the Photosystem II complex in the thermophilic cyanobacterium Thermosynechococcus elongatus. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2010; 1797:1546-54. [DOI: 10.1016/j.bbabio.2010.03.020] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/17/2010] [Revised: 03/23/2010] [Accepted: 03/24/2010] [Indexed: 11/16/2022]
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Sinha RK, Tiwari A, Pospíšil P. Water-splitting manganese complex controls light-induced redox changes of cytochrome b 559 in Photosystem II. J Bioenerg Biomembr 2010; 42:337-44. [DOI: 10.1007/s10863-010-9299-2] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2010] [Accepted: 04/13/2010] [Indexed: 11/28/2022]
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40
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Yanykin DV, Khorobrykh AA, Khorobrykh SA, Klimov VV. Photoconsumption of molecular oxygen on both donor and acceptor sides of photosystem II in Mn-depleted subchloroplast membrane fragments. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2010; 1797:516-23. [DOI: 10.1016/j.bbabio.2010.01.014] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/12/2009] [Revised: 01/03/2010] [Accepted: 01/15/2010] [Indexed: 10/19/2022]
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42
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Low-temperature electron transfer suggests two types of QA in intact photosystem II. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2010; 1797:339-46. [DOI: 10.1016/j.bbabio.2009.12.001] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/05/2009] [Revised: 12/01/2009] [Accepted: 12/03/2009] [Indexed: 11/23/2022]
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43
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D1 protein variants in Photosystem II from Thermosynechococcus elongatus studied by low temperature optical spectroscopy. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2010; 1797:11-9. [DOI: 10.1016/j.bbabio.2009.07.007] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/03/2009] [Revised: 07/17/2009] [Accepted: 07/20/2009] [Indexed: 11/24/2022]
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44
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Cox N, Jin L, Jaszewski A, Smith PJ, Krausz E, Rutherford AW, Pace R. The semiquinone-iron complex of photosystem II: structural insights from ESR and theoretical simulation; evidence that the native ligand to the non-heme iron is carbonate. Biophys J 2009; 97:2024-33. [PMID: 19804734 DOI: 10.1016/j.bpj.2009.06.033] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2009] [Revised: 06/23/2009] [Accepted: 06/24/2009] [Indexed: 11/16/2022] Open
Abstract
The semiquinone-iron complex of photosystem II was studied using electron spin resonance (ESR) spectroscopy and density functional theory calculations. Two forms of the signal were investigated: 1), the native g approximately 1.9 form; and 2), the g approximately 1.84 form, which is well known in purple bacterial reaction centers and occurs in photosystem II when treated with formate. The g approximately 1.9 form shows low- and high-field edges at g approximately 3.5 and g < 0.8, respectively, and resembles the g approximately 1.84 form in terms of shape and width. Both types of ESR signal were simulated using the theoretical approach used previously for the BRC complex, a spin Hamiltonian formalism in which the semiquinone radical magnetically interacts (J approximately 1 cm(-1)) with the nearby high-spin Fe(2+). The two forms of ESR signal differ mainly by an axis rotation of the exchange coupling tensor (J) relative to the zero-field tensor (D) and a small increase in the zero-field parameter D ( approximately 6 cm(-1)). Density functional theory calculations were conducted on model semiquinone-iron systems to identify the physical nature of these changes. The replacement of formate (or glutamate in the bacterial reaction centers) by bicarbonate did not result in changes in the coupling environment. However, when carbonate (CO(3)(2-)) was used instead of bicarbonate, the exchange and zero-field tensors did show changes that matched those obtained from the spectral simulations. This indicates that 1), the doubly charged carbonate ion is responsible for the g approximately 1.9 form of the semiquinone-iron signal; and 2), carbonate, rather than bicarbonate, is the ligand to the iron.
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Affiliation(s)
- Nicholas Cox
- Research School of Chemistry, Australian National University, Canberra, Australia.
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45
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Koyama Y, Miki T, Wang XF, Nagae H. Dye-sensitized solar cells based on the principles and materials of photosynthesis: mechanisms of suppression and enhancement of photocurrent and conversion efficiency. Int J Mol Sci 2009; 10:4575-4622. [PMID: 20087456 PMCID: PMC2808002 DOI: 10.3390/ijms10114575] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2009] [Revised: 09/08/2009] [Accepted: 10/23/2009] [Indexed: 11/20/2022] Open
Abstract
Attempts have been made to develop dye-sensitized solar cells based on the principles and materials of photosynthesis: We first tested photosynthetic pigments, carotenoids (Cars), chlorophylls (Chls) and their derivatives, to find sensitizers showing reasonable performance (photocurrent and conversion efficiency). We then tried to introduce the principles of photosynthesis, including electron transfer and energy transfer from Car to Phe a. Also, we tried co-sensitization using the pheophorbide (Phe) a and Chl c2 pair which further enhanced the performance of the component sensitizers as follows: Jsc = 9.0 + 13.8 → 14.0 mA cm−2 and η = 3.4 + 4.6 → 5.4%.
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Affiliation(s)
- Yasushi Koyama
- Faculty of Science and Technology, Kwansei Gakuin University, Sanda, Hyogo 669-1337, Japan
- Author to whom correspondence should be addressed; E-Mail:
; Tel.: +81-79-565-8408; Fax: +81-79-565-8408, +81-79-565-9077
| | - Takeshi Miki
- Faculty of Science and Technology, Kwansei Gakuin University, Sanda, Hyogo 669-1337, Japan
| | - Xiao-Feng Wang
- Faculty of Science and Technology, Kwansei Gakuin University, Sanda, Hyogo 669-1337, Japan
- Graduate School of Engineering, Gifu University, Yanagido, Gifu 501-1193, Japan
| | - Hiroyoshi Nagae
- Kobe City University of Foreign Studies, Gakuen Higashimachi, Nishi-ku, Kobe 651-2187, Japan
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46
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Gao Y, Shinopoulos KE, Tracewell CA, Focsan AL, Brudvig GW, Kispert LD. Formation of carotenoid neutral radicals in photosystem II. J Phys Chem B 2009; 113:9901-8. [PMID: 19552399 DOI: 10.1021/jp8075832] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Abstract
beta-Carotene radicals produced in the hexagonal pores of the molecular sieve Cu(II)-MCM-41 were studied by ENDOR and visible/near-IR spectroscopies. ENDOR studies showed that neutral radicals of beta-carotene were produced in humid air under ambient fluorescent light. The maximum absorption wavelengths of the neutral radicals were measured and were additionally predicted by using time-dependent density functional theory (TD-DFT) calculations. An absorption peak at 750 nm, assigned to the neutral radical with a proton loss from the 4(4') position of the beta-carotene radical cation in Cu(II)-MCM-41, was also observed in photosystem II (PS II) samples using near-IR spectroscopy after illumination at 20 K. This peak was previously unassigned in PS II samples. The intensity of the absorption peak at 750 nm relative to the absorption of chlorophyll radical cations and beta-carotene radical cations increased with increasing pH of the PS II sample, providing further evidence that the absorption peak is due to the deprotonation of the beta-carotene radical cation. Based on a consideration of possible proton acceptors that are adjacent to beta-carotene molecules in photosystem II, as modeled in the X-ray crystal structure of Guskov et al. Nat. Struct. Mol. Biol. 2009, 16, 334-342, an electron-transfer pathway from a beta-carotene molecule with an adjacent proton acceptor to P680*+ is proposed.
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Affiliation(s)
- Yunlong Gao
- Department of Chemistry, Yale University, P.O. Box 208107, New Haven, Connecticut 06520-8107, USA
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47
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Sjöholm J, Havelius KGV, Mamedov F, Styring S. The S0 State of the Water Oxidizing Complex in Photosystem II: pH Dependence of the EPR Split Signal Induction and Mechanistic Implications. Biochemistry 2009; 48:9393-404. [DOI: 10.1021/bi901177w] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Johannes Sjöholm
- Molecular Biomimetics, Department of Photochemistry and Molecular Science, Uppsala University, Ångström Laboratory, P.O. Box 523, S-751 20 Uppsala, Sweden
| | - Kajsa G. V. Havelius
- Molecular Biomimetics, Department of Photochemistry and Molecular Science, Uppsala University, Ångström Laboratory, P.O. Box 523, S-751 20 Uppsala, Sweden
| | - Fikret Mamedov
- Molecular Biomimetics, Department of Photochemistry and Molecular Science, Uppsala University, Ångström Laboratory, P.O. Box 523, S-751 20 Uppsala, Sweden
| | - Stenbjörn Styring
- Molecular Biomimetics, Department of Photochemistry and Molecular Science, Uppsala University, Ångström Laboratory, P.O. Box 523, S-751 20 Uppsala, Sweden
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48
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Superoxide oxidase and reductase activity of cytochrome b559 in photosystem II. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2009; 1787:985-94. [DOI: 10.1016/j.bbabio.2009.03.017] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/16/2008] [Revised: 03/19/2009] [Accepted: 03/26/2009] [Indexed: 11/21/2022]
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49
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Cox N, Ho FM, Pewnim N, Steffen R, Smith PJ, Havelius KG, Hughes JL, Debono L, Styring S, Krausz E, Pace RJ. The S1 split signal of photosystem II; a tyrosine–manganese coupled interaction. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2009; 1787:882-9. [DOI: 10.1016/j.bbabio.2009.03.023] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/10/2008] [Revised: 03/26/2009] [Accepted: 03/30/2009] [Indexed: 10/20/2022]
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Pospísil P. Production of reactive oxygen species by photosystem II. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2009; 1787:1151-60. [PMID: 19463778 DOI: 10.1016/j.bbabio.2009.05.005] [Citation(s) in RCA: 213] [Impact Index Per Article: 14.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/10/2008] [Revised: 05/05/2009] [Accepted: 05/07/2009] [Indexed: 11/29/2022]
Abstract
Photosysthetic cleavage of water molecules to molecular oxygen is a crucial process for all aerobic life on the Earth. Light-driven oxidation of water occurs in photosystem II (PSII) - a pigment-protein complex embedded in the thylakoid membrane of plants, algae and cyanobacteria. Electron transport across the thylakoid membrane terminated by NADPH and ATP formation is inadvertently coupled with the formation of reactive oxygen species (ROS). Reactive oxygen species are mainly produced by photosystem I; however, under certain circumstances, PSII contributes to the overall formation of ROS in the thylakoid membrane. Under limitation of electron transport reaction between both photosystems, photoreduction of molecular oxygen by the reducing side of PSII generates a superoxide anion radical, its dismutation to hydrogen peroxide and the subsequent formation of a hydroxyl radical terminates the overall process of ROS formation on the PSII electron acceptor side. On the PSII electron donor side, partial or complete inhibition of enzymatic activity of the water-splitting manganese complex is coupled with incomplete oxidation of water to hydrogen peroxide. The review points out the mechanistic aspects in the production of ROS on both the electron acceptor and electron donor side of PSII.
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Affiliation(s)
- Pavel Pospísil
- Laboratory of Biophysics, Department of Experimental Physics, Faculty of Science, Palacký University, Olomouc, Czech Republic.
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