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Vasilieva LG, Kaminskaya OP, Yakovlev AG, Shkuropatov AY, Semenov AY, Nadtochenko VA, Krasnovsky AA, Parson WW, Allakhverdiev SI, Govindjee G. In memory of Vladimir Anatolievich Shuvalov (1943-2022): an outstanding biophysicist. PHOTOSYNTHESIS RESEARCH 2022; 154:207-223. [PMID: 36070062 DOI: 10.1007/s11120-022-00932-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/21/2022] [Accepted: 06/01/2022] [Indexed: 06/15/2023]
Abstract
We present here a tribute to one of the foremost biophysicists of our time, Vladimir Anatolievich Shuvalov, who made important contributions in bioenergetics, especially on the primary steps of conversion of light energy into charge-separated states in both anoxygenic and oxygenic photosynthesis. For this, he and his research team exploited pico- and femtosecond transient absorption spectroscopy, photodichroism & circular dichroism spectroscopy, light-induced FTIR (Fourier-transform infrared) spectroscopy, and hole-burning spectroscopy. We remember him for his outstanding leadership and for being a wonderful mentor to many scientists in this area. Reminiscences by many [Suleyman Allakhverdiev (Russia); Robert Blankenship (USA); Richard Cogdell (UK); Arvi Freiberg (Estonia); Govindjee Govindjee (USA); Alexander Krasnovsky, jr, (Russia); William Parson (USA); Andrei Razjivin (Russia); Jian- Ren Shen (Japan); Sergei Shuvalov (Russia); Lyudmilla Vasilieva (Russia); and Andrei Yakovlev (Russia)] have included not only his wonderful personal character, but his outstanding scientific research.
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Affiliation(s)
- Lyudmila G Vasilieva
- Institute of Basic Biological Problems of the Russian Academy of Sciences, Pushchino Moscow Region, Pushchino, Russian Federation
| | - Olga P Kaminskaya
- Institute of Basic Biological Problems of the Russian Academy of Sciences, Pushchino Moscow Region, Pushchino, Russian Federation
| | - Andrei G Yakovlev
- A.N. Belozersky Institute of Physical-Chemical Biology, Lomonosov Moscow State University, Leninskie Gory, 1, Moscow, 119992, Russian Federation
| | - Anatoliy Ya Shkuropatov
- Institute of Basic Biological Problems of the Russian Academy of Sciences, Pushchino Moscow Region, Pushchino, Russian Federation
| | - Alexey Yu Semenov
- A.N. Belozersky Institute of Physical-Chemical Biology, Lomonosov Moscow State University, Leninskie Gory, 1, Moscow, 119992, Russian Federation
| | - Victor A Nadtochenko
- N.N. Semenov Federal Research Center for Chemical Physics, Russian Academy of Sciences, Kosygina St. 4, Moscow, 117977, Russian Federation
| | - Alexander A Krasnovsky
- Bach Institute of Biochemistry, Federal Research Center of Biotechnology, Russian Academy of Sciences, Moscow, 119071, Russian Federation
| | - William W Parson
- Department of Biochemistry, University of Washington, Seattle, WA, 98195, USA.
| | - Suleyman I Allakhverdiev
- Institute of Basic Biological Problems of the Russian Academy of Sciences, Pushchino Moscow Region, Pushchino, Russian Federation.
- K.A. Timiryazev Institute of Plant Physiology, Russian Academy of Sciences, Moscow, Russian Federation.
| | - Govindjee Govindjee
- Department of Biochemistry, Department of Plant Biology and Center of Biophysics and Quantitative Biology, University of Illinois at Urbana-Champaign, 289 Morrill Hall, 505 South Goodwin Avenue, Urbana, IL, 61801, USA.
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Gorka M, Charles P, Kalendra V, Baldansuren A, Lakshmi KV, Golbeck JH. A dimeric chlorophyll electron acceptor differentiates type I from type II photosynthetic reaction centers. iScience 2021; 24:102719. [PMID: 34278250 PMCID: PMC8267441 DOI: 10.1016/j.isci.2021.102719] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2020] [Revised: 05/17/2021] [Accepted: 06/09/2021] [Indexed: 01/09/2023] Open
Abstract
This research addresses one of the most compelling issues in the field of photosynthesis, namely, the role of the accessory chlorophyll molecules in primary charge separation. Using a combination of empirical and computational methods, we demonstrate that the primary acceptor of photosystem (PS) I is a dimer of accessory and secondary chlorophyll molecules, Chl2A and Chl3A, with an asymmetric electron charge density distribution. The incorporation of highly coupled donors and acceptors in PS I allows for extensive delocalization that prolongs the lifetime of the charge-separated state, providing for high quantum efficiency. The discovery of this motif has widespread implications ranging from the evolution of naturally occurring reaction centers to the development of a new generation of highly efficient artificial photosynthetic systems. Video abstract
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Affiliation(s)
- Michael Gorka
- Department of Biochemistry and Molecular Biology, The Pennsylvania State University, University Park, PA 16802, USA
| | - Philip Charles
- Department of Chemistry and Chemical Biology and The Baruch '60 Center for Biochemical Solar Energy Research, Rensselaer Polytechnic Institute, Troy, NY 12180, USA
| | - Vidmantas Kalendra
- Department of Chemistry and Chemical Biology and The Baruch '60 Center for Biochemical Solar Energy Research, Rensselaer Polytechnic Institute, Troy, NY 12180, USA
| | - Amgalanbaatar Baldansuren
- Department of Chemistry and Chemical Biology and The Baruch '60 Center for Biochemical Solar Energy Research, Rensselaer Polytechnic Institute, Troy, NY 12180, USA
| | - K V Lakshmi
- Department of Chemistry and Chemical Biology and The Baruch '60 Center for Biochemical Solar Energy Research, Rensselaer Polytechnic Institute, Troy, NY 12180, USA
| | - John H Golbeck
- Department of Biochemistry and Molecular Biology, The Pennsylvania State University, University Park, PA 16802, USA.,Department of Chemistry, The Pennsylvania State University, University Park, PA 16802, USA
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Gorka M, Gruszecki E, Charles P, Kalendra V, Lakshmi KV, Golbeck JH. Two-dimensional HYSCORE spectroscopy reveals a histidine imidazole as the axial ligand to Chl 3A in the M688H PsaA genetic variant of Photosystem I. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2021; 1862:148424. [PMID: 33785317 DOI: 10.1016/j.bbabio.2021.148424] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 10/01/2020] [Revised: 02/28/2021] [Accepted: 03/24/2021] [Indexed: 12/17/2022]
Abstract
Recent studies on Photosystem I (PS I) have shown that the six core chlorophyll a molecules are highly coupled, allowing for efficient creation and stabilization of the charge-separated state. One area of particular interest is the identity and function of the primary acceptor, A0, as the factors that influence its ultrafast processes and redox properties are not yet fully elucidated. It was recently shown that A0 exists as a dimer of the closely-spaced Chl2/Chl3 molecules wherein the reduced A0- state has an asymmetric distribution of electron spin density that favors Chl3. Previous experimental work in which this ligand was changed to a hard base (histidine, M688HPsaA) revealed severely impacted electron transfer processes at both the A0 and A1 acceptors; molecular dynamics simulations further suggested two distinct conformations of PS I in which the His residue coordinates and forms a hydrogen bond to the A0 and A1 cofactors, respectively. In this study, we have applied 2D HYSCORE spectroscopy in conjunction with molecular dynamics simulations and density functional theory calculations to the study of the M688HPsaA variant. Analysis of the hyperfine parameters demonstrates that the His imidazole serves as the axial ligand to the central Mg2+ ion in Chl3A in the M688HPsaA variant. Although the change in ligand identity does not alter delocalization of electron density over the Chl2/Chl3 dimer, a small shift in the asymmetry of delocalization, coupled with the electron withdrawing properties of the ligand, most likely accounts for the inhibition of forward electron transfer in the His-ligated conformation.
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Affiliation(s)
- Michael Gorka
- Department of Biochemistry and Molecular Biology, The Pennsylvania State University, State College, PA 16802, USA
| | - Elijah Gruszecki
- Department of Chemistry and Chemical Biology and The Baruch '60 Center for Biochemical Solar Energy Research, Rensselaer Polytechnic Institute, Troy, NY 12180, USA
| | - Philip Charles
- Department of Chemistry and Chemical Biology and The Baruch '60 Center for Biochemical Solar Energy Research, Rensselaer Polytechnic Institute, Troy, NY 12180, USA
| | - Vidmantas Kalendra
- Department of Chemistry and Chemical Biology and The Baruch '60 Center for Biochemical Solar Energy Research, Rensselaer Polytechnic Institute, Troy, NY 12180, USA
| | - K V Lakshmi
- Department of Chemistry and Chemical Biology and The Baruch '60 Center for Biochemical Solar Energy Research, Rensselaer Polytechnic Institute, Troy, NY 12180, USA.
| | - John H Golbeck
- Department of Biochemistry and Molecular Biology, The Pennsylvania State University, State College, PA 16802, USA; Department of Chemistry, The Pennsylvania State University, State College, PA 16802, USA.
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He Z, Ferlez B, Kurashov V, Tank M, Golbeck JH, Bryant DA. Reaction centers of the thermophilic microaerophile, Chloracidobacterium thermophilum (Acidobacteria) I: biochemical and biophysical characterization. PHOTOSYNTHESIS RESEARCH 2019; 142:87-103. [PMID: 31161318 DOI: 10.1007/s11120-019-00650-9] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/17/2019] [Accepted: 05/27/2019] [Indexed: 06/09/2023]
Abstract
Chloracidobacterium thermophilum is a microaerophilic, anoxygenic member of the green chlorophototrophic bacteria. This bacterium is the first characterized oxygen-requiring chlorophototroph with chlorosomes, the FMO protein, and homodimeric type-1 reaction centers (RCs). The RCs of C. thermophilum are also unique because they contain three types of chlorophylls, bacteriochlorophyll aP esterified with phytol, Chl aPD esterified with Δ2,6-phytadienol, and Zn-BChl aP' esterified with phytol, in the approximate molar ratio 32:24:4. The light-induced difference spectrum of these RCs had a bleaching maximum at 839 nm and also revealed an electrochromic bandshift that is probably derived from a BChl a molecule near P840+. The FX [4Fe-4S] cluster had a midpoint potential of ca. - 581 mV, and the spectroscopic properties of the P+ F X - spin-polarized radical pair were very similar to those of reaction centers of heliobacteria and green sulfur bacteria. The data further indicate that electron transfer occurs directly from A0- to FX, as occurs in other homodimeric type-1 RCs. Washing experiments with isolated membranes suggested that the PscB subunit of these reaction centers is more tightly bound than PshB in heliobacteria. Thus, the reaction centers of C. thermophilum have some properties that resemble other homodimeric reaction centers but also have specific properties that are more similar to those of Photosystem I. These differences probably contribute to protection of the electron transfer chain from oxygen, contributing to the oxygen tolerance of this microaerophile.
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Affiliation(s)
- Zhihui He
- Department of Biochemistry and Molecular Biology, The Pennsylvania State University, S-002 Frear Building, University Park, PA, 16802, USA
| | - Bryan Ferlez
- Department of Biochemistry and Molecular Biology, The Pennsylvania State University, S-002 Frear Building, University Park, PA, 16802, USA
- MSU-DOE Plant Research Laboratory, Michigan State University, 612 Wilson Road, East Lansing, MI, 48824, USA
| | - Vasily Kurashov
- Department of Biochemistry and Molecular Biology, The Pennsylvania State University, S-002 Frear Building, University Park, PA, 16802, USA
| | - Marcus Tank
- Department of Biochemistry and Molecular Biology, The Pennsylvania State University, S-002 Frear Building, University Park, PA, 16802, USA
- Department of Biological Sciences, Tokyo Metropolitan University, 1-1 Minami-Osawa, Hachioji, Tokyo, 192-0397, Japan
| | - John H Golbeck
- Department of Biochemistry and Molecular Biology, The Pennsylvania State University, S-002 Frear Building, University Park, PA, 16802, USA
- Department of Chemistry, The Pennsylvania State University, University Park, PA, 16802, USA
| | - Donald A Bryant
- Department of Biochemistry and Molecular Biology, The Pennsylvania State University, S-002 Frear Building, University Park, PA, 16802, USA.
- Department of Chemistry and Biochemistry, Montana State University, Bozeman, MT, 59717, USA.
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Multiple pathways of charge recombination revealed by the temperature dependence of electron transfer kinetics in cyanobacterial photosystem I. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2019; 1860:601-610. [DOI: 10.1016/j.bbabio.2019.06.008] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/07/2019] [Revised: 05/22/2019] [Accepted: 06/15/2019] [Indexed: 11/20/2022]
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Gelzinis A, Augulis R, Butkus V, Robert B, Valkunas L. Two-dimensional spectroscopy for non-specialists. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2019; 1860:271-285. [DOI: 10.1016/j.bbabio.2018.12.006] [Citation(s) in RCA: 31] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/14/2018] [Revised: 11/14/2018] [Accepted: 12/08/2018] [Indexed: 12/20/2022]
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Kurashov V, Gorka M, Milanovsky GE, Johnson TW, Cherepanov DA, Semenov AY, Golbeck JH. Critical evaluation of electron transfer kinetics in P700–FA/FB, P700–FX, and P700–A1 Photosystem I core complexes in liquid and in trehalose glass. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2018; 1859:1288-1301. [DOI: 10.1016/j.bbabio.2018.09.367] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/07/2018] [Revised: 09/15/2018] [Accepted: 09/17/2018] [Indexed: 12/12/2022]
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Molotokaite E, Remelli W, Casazza AP, Zucchelli G, Polli D, Cerullo G, Santabarbara S. Trapping Dynamics in Photosystem I-Light Harvesting Complex I of Higher Plants Is Governed by the Competition Between Excited State Diffusion from Low Energy States and Photochemical Charge Separation. J Phys Chem B 2017; 121:9816-9830. [DOI: 10.1021/acs.jpcb.7b07064] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Egle Molotokaite
- Centro
Studi sulla Biologia Cellulare e Molecolare delle Piante, CNR, Via Celoria 26, 20133 Milan, Italy
| | - William Remelli
- Centro
Studi sulla Biologia Cellulare e Molecolare delle Piante, CNR, Via Celoria 26, 20133 Milan, Italy
| | - Anna Paola Casazza
- Istituto
di Biologia e Biotecnologia Agraria, Consiglio Nazionale delle Ricerche, Via Bassini 15a, 20133 Milano, Italy
| | - Giuseppe Zucchelli
- Centro
Studi sulla Biologia Cellulare e Molecolare delle Piante, CNR, Via Celoria 26, 20133 Milan, Italy
| | - Dario Polli
- Istituto di Fotonica e Nanotecnologie del CNR, Dipartimento di Fisica, Politecnico di Milano, P.zza Leonardo
da Vinci 32, 20133 Milano, Italy
- Center
for Nano Science and Technology at Polimi, Istituto Italiano di Tecnologia, Via Giovanni Pascoli, 70/3, 20133 Milano, Italy
| | - Giulio Cerullo
- Istituto di Fotonica e Nanotecnologie del CNR, Dipartimento di Fisica, Politecnico di Milano, P.zza Leonardo
da Vinci 32, 20133 Milano, Italy
| | - Stefano Santabarbara
- Centro
Studi sulla Biologia Cellulare e Molecolare delle Piante, CNR, Via Celoria 26, 20133 Milan, Italy
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Shuvalov VA. My journey in photosynthesis research. PHOTOSYNTHESIS RESEARCH 2015; 125:5-8. [PMID: 25645566 DOI: 10.1007/s11120-015-0077-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/24/2014] [Accepted: 01/05/2015] [Indexed: 06/04/2023]
Abstract
At the invitation of Suleyman I. Allakhverdiev, I provide here a brief autobiography for this special issue that recognizes my service and research for the larger international community of photosynthesis research.
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Affiliation(s)
- Vladimir A Shuvalov
- Institute of Basic Biological Problems, RAS, 142290, Pushchino, Moscow Region, Russia,
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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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Forman A, Davis MS, Fujita I, Hanson LK, Smith KM, Fajer J. Mechanisms of Energy Transduction in Plant Photosynthesis: ESR, ENDOR and MOs of the Primary Acceptors. Isr J Chem 2013. [DOI: 10.1002/ijch.198100049] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Ke B. The Reaction-Center Complex of Photosystem II: Early Electron-Transfer Components and Reactions. Isr J Chem 2013. [DOI: 10.1002/ijch.198100052] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Chauvet A, Dashdorj N, Golbeck JH, Johnson TW, Savikhin S. Spectral resolution of the primary electron acceptor A0 in Photosystem I. J Phys Chem B 2012; 116:3380-6. [PMID: 22332796 DOI: 10.1021/jp211246a] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The reduced state of the primary electron acceptor of Photosystem I, A(0), was resolved spectroscopically in its lowest energy Q(y) region for the first time without the addition of chemical reducing agents and without extensive data manipulation. To carry this out, we used the menB mutant of Synechocystis sp. PCC 6803 in which phylloquinone is replaced by plastoquinone-9 in the A(1) sites of Photosystem I. The presence of plastoquinone-9 slows electron transfer from A(0) to A(1), leading to a long-lived A(0)(-) state. This allows its spectral signature to be readily detected in a time-resolved optical pump-probe experiment. The maximum bleaching (A(0)(-) - A(0)) was found to occur at 684 nm with a corresponding extinction coefficient of 43 mM(-1) cm(-1). The data show evidence for an electrochromic shift of an accessory chlorophyll pigment, suggesting that the latter Q(y) absorption band is centered around 682 nm.
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Affiliation(s)
- Adrien Chauvet
- Department of Physics, Purdue University, 525 Northwestern Ave, West Lafayette, Indiana 47907, USA
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Holzwarth AR, Schatz G, Brock H, Bittersmann E. Energy transfer and charge separation kinetics in photosystem I: Part 1: Picosecond transient absorption and fluorescence study of cyanobacterial photosystem I particles. Biophys J 2010; 64:1813-26. [PMID: 19431900 DOI: 10.1016/s0006-3495(93)81552-2] [Citation(s) in RCA: 104] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The energy transfer and charge separation kinetics of a photosystem I (PS I) core particle of an antenna size of 100 chlorophyll/P700 has been studied by combined fluorescence and transient absorption kinetics with picosecond resolution. This is the first combined picosecond study of transient absorption and fluorescence carried out on a PS I particle and the results are consistent with each other. The data were analyzed by both global lifetime and global target analysis procedures. In fluorescence major lifetime components were found to be 12 and 36 ps. The shorter-lived one shows a negative amplitude at long wavelengths and is attributed to an energy transfer process between pigments in the main antenna Chl pool and a small long-wavelength Chl pool emitting around 720 nm whereas the longer-lived component is assigned to the overall charge separation lifetime. The lifetimes resolved in transient absorption are 7-8 ps, 33 ps, and [unk]1 ns. The shortest-lived one is assigned to energy transfer between the same pigment pools as observed also in fluorescence kinetics, the middle component of 33 ps to the overall charge separation, and the long-lived component to the lifetime of the oxidized primary donor P700(+). The transient absorption data indicate an even faster, but kinetically unresolved energy transfer component in the main Chl pool with a lifetime <3 ps. Several kinetic models were tested on both the fluorescence and the picosecond absorption data by global target analysis procedures. A model where the long-wave pigments are spatially and kinetically connected with the reaction center P700 is favored over a model where P700 is connected more closely with the main Chl pool. Our data show that the charge separation kinetics in these PS I particles is essentially trap limited. The relevance of our data with respect to other time-resolved studies on PS I core particles is discussed, in particular with respect to the nature and function of the long-wave pigments. From the transient absorption data we do not see any evidence for the occurrence of a reduced Chl primary electron acceptor, but we also can not exclude that possibility, provided that reoxidation of that acceptor should occur within a time <40 ps.
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Affiliation(s)
- A R Holzwarth
- Max-Planck-Institut für Strahlenchemie, D-4330 Mülheim an der Ruhr, Germany
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Abstract
Picosecond time-resolved fluorescence measurements have been taken on a detergent-free P700-enriched complex at room temperature isolated from the blue-green alga Phormidium luridum with a chlorophyll a to reaction center ratio of 100. Emission at greater than 665 nm is characterized by two exponential-decay components. A fast component, which dominates the initial decay with an average lifetime of 16 ps and 87% amplitude, is attributed to excitations in the core antenna chlorophyll-proteins, which are rapidly trapped by the primary electron donor, P700. A second component, with an average lifetime of 106 ps and 13% amplitude, is attributed to the peripheral antenna proteins. For 532-nm, 30-ps pulse excitation the results are virtually independent of fluence in the range of 2 x 10(12) to 4 x 10(16) photons/cm(2) and the oxidation state of P700. Addition of sodium dodecyl sulfate to 0.1% causes the second component's lifetime to increase by an average of a factor of 2.5. Only minor changes are observed in the first component's lifetime and the relative amplitudes of the two components. Two fractions isolated from the detergent-treated samples have also been examined. Our results indicate that excitation energy transfer within photosystem I is very efficient and that the excitation kinetics of the antennae may be limited by the trapping rate of P700 or strongly affected by the heterogeneity of the antennae.
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Pashchenko VZ, Rubin LB. Second All-Union School on Applications of Lasers in Biology, Tbilisi, November 24–29, 1980 (Pulsed fluorometry of primary photosynthesis processes in higher plants). ACTA ACUST UNITED AC 2007. [DOI: 10.1070/qe1981v011n12abeh008651] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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Santabarbara S, Heathcote P, Evans MCW. Modelling of the electron transfer reactions in Photosystem I by electron tunnelling theory: The phylloquinones bound to the PsaA and the PsaB reaction centre subunits of PS I are almost isoenergetic to the iron–sulfur cluster FX. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2005; 1708:283-310. [PMID: 15975545 DOI: 10.1016/j.bbabio.2005.05.001] [Citation(s) in RCA: 69] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/27/2004] [Revised: 04/12/2005] [Accepted: 05/03/2005] [Indexed: 10/25/2022]
Abstract
Photosystem I is a large macromolecular complex located in the thylakoid membranes of chloroplasts and in cyanobacteria that catalyses the light driven reduction of ferredoxin and oxidation of plastocyanin. Due to the very negative redox potential of the primary electron transfer cofactors accepting electrons, direct estimation by redox titration of the energetics of the system is hampered. However, the rates of electron transfer reactions are related to the thermodynamic properties of the system. Hence, several spectroscopic and biochemical techniques have been employed, in combination with the classical Marcus theory for electron transfer tunnelling, in order to access these parameters. Nevertheless, the values which have been presented are very variable. In particular, for the case of the tightly bound phylloquinone molecule A(1), the values of the redox potentials reported in the literature vary over a range of about 350 mV. Previous models of Photosystem I have assumed a unidirectional electron transfer model. In the present study, experimental evidence obtained by means of time resolved absorption, photovoltage, and electron paramagnetic resonance measurements are reviewed and analysed in terms of a bi-directional kinetic model for electron transfer reactions. This model takes into consideration the thermodynamic equilibrium between the iron-sulfur centre F(X) and the phylloquinone bound to either the PsaA (A(1A)) or the PsaB (A(1B)) subunit of the reaction centre and the equilibrium between the iron-sulfur centres F(A) and F(B). The experimentally determined decay lifetimes in the range of sub-picosecond to the microsecond time domains can be satisfactorily simulated, taking into consideration the edge-to-edge distances between redox cofactors and driving forces reported in the literature. The only exception to this general behaviour is the case of phylloquinone (A(1)) reoxidation. In order to describe the reported rates of the biphasic decay, of about 20 and 200 ns, associated with this electron transfer step, the redox potentials of the quinones are estimated to be almost isoenergetic with that of the iron sulfur centre F(X). A driving force in the range of 5 to 15 meV is estimated for these reactions, being slightly exergonic in the case of the A(1B) quinone and slightly endergonic, in the case of the A(1A) quinone. The simulation presented in this analysis not only describes the kinetic data obtained for the wild type samples at room temperature and is consistent with estimates of activation energy by the analysis of temperature dependence, but can also explain the effect of the mutations around the PsaB quinone binding pocket. A model of the overall energetics of the system is derived, which suggests that the only substantially irreversible electron transfer reactions are the reoxidation of A(0) on both electron transfer branches and the reduction of F(A) by F(X).
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Affiliation(s)
- Stefano Santabarbara
- School of Biological Sciences, Queen Mary, University of London, Mile End Road, London E1 4NS, UK.
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Hauska G. Transmembrane charge separation within the large subunit of photosystem I-reaction centers from chloroplasts. FEBS Lett 2001. [DOI: 10.1016/0014-5793(80)80259-6] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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21
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22
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Maeda H, Watanabe T, Kobayashi S, Hiyama T. Normal-phase HPLC quantitation of chlorophyll a' and phylloquinone in Photosystem I particles. PHOTOSYNTHESIS RESEARCH 1993; 35:179-184. [PMID: 24318684 DOI: 10.1007/bf00014748] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/30/1992] [Accepted: 09/09/1992] [Indexed: 06/02/2023]
Abstract
Fractionated Photosystem (PS) I particles consisting of six, five or two core proteins were analyzed by HPLC for chlorophyll (Chl) a' and phylloquinone (PhQ). Each particle had a Chl a/P700 molar ratio of 50-55 and contained ca. 2 molecules of Chl a' per P700. Deliberate control of eluent composition led to isolated elution of PhQ and β-carotene in the normal-phase chromatogram. Based on these a simple HPLC procedure has been established to determine the PhQ/P700 molar ratio, which was ca. 2 for the larger two PS I particles and ca. 1 for the smallest particle, in line with previous reports.
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Affiliation(s)
- H Maeda
- Institute of Industrial Science, University of Tokyo, Roppongi, Minato-ku, 106, Tokyo, Japan
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24
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Holzwarth AR. Applications of ultrafast laser spectroscopy for the study of biological systems. Q Rev Biophys 1989; 22:239-326. [PMID: 2695961 DOI: 10.1017/s0033583500002985] [Citation(s) in RCA: 65] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
The discovery of mode-locked laser operation now nearly two decades ago has started a development which enables researchers to probe the dynamics of ultrafast physical and chemical processes at the molecular level on shorter and shorter time scales. Naturally the first applications were in the fields of photophysics and photochemistry where it was then possible for the first time to probe electronic and vibrational relaxation processes on a sub-nanosecond timescale. The development went from lasers producing pulses of many picoseconds to the shortest pulses which are at present just a few femtoseconds long. Soon after their discovery ultrashort pulses were applied also to biological systems which has revealed a wealth of information contributing to our understanding of a broadrange of biological processes on the molecular level.It is the aim of this review to discuss the recent advances and point out some future trends in the study of ultrafast processes in biological systems using laser techniques. The emphasis will be mainly on new results obtained during the last 5 or 6 years. The term ultrafast means that I shall restrict myself to sub-nanosecond processes with a few exceptions.
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Affiliation(s)
- A R Holzwarth
- Max-Planck-Institut für Strahlenchemie, Mülheim/Ruhr, FRG
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25
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Spectral Hole-Burning in Crystalline and Amorphous Organic Solids. Optical Relaxation Processes at Low Temperature. RELAXATION PROCESSES IN MOLECULAR EXCITED STATES 1989. [DOI: 10.1007/978-94-009-0863-5_4] [Citation(s) in RCA: 31] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
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26
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Mathis P, Ikegami I, Setif P. Nanosecond flash studies of the absorption spectrum of the Photosystem I primary acceptor Ao. PHOTOSYNTHESIS RESEARCH 1988; 16:203-210. [PMID: 24429527 DOI: 10.1007/bf00028839] [Citation(s) in RCA: 30] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/06/1987] [Accepted: 12/08/1987] [Indexed: 06/03/2023]
Abstract
Photosystem I particles devoid of the secondary electron acceptor A1 were studied by nanosecond flash absorption. The primary radical pair (P-700(+), A0 (-)) decays with a half-time of 35 ns. The difference spectrum was measured (400-870 nm). After subtraction of the P-700(+)/P-700 difference spectrum, the A0 (-)/A0 was obtained. It includes bleachings centered at 690 and 430 nm, and broad positive bands in the near infra-red and the blue-green. This spectrum is consistent with A0 being chlorophyll a absorbing at 690 nm.
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Affiliation(s)
- P Mathis
- Service de Biophysquie, Département de Biologie, CEN Saclay, 91191, Gif-sur-Yvette Cedex, France
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27
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Gillie J, Fearey B, Hayes J, Small G, Golbeck J. Persistent hole burning of the primary donor state of photosystem i: strong linear electron-phonon coupling. Chem Phys Lett 1987. [DOI: 10.1016/0009-2614(87)87144-0] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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29
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Golbeck JH. Structure, function and organization of the Photosystem I reaction center complex. BIOCHIMICA ET BIOPHYSICA ACTA 1987; 895:167-204. [PMID: 3333014 DOI: 10.1016/s0304-4173(87)80002-2] [Citation(s) in RCA: 177] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Affiliation(s)
- J H Golbeck
- Department of Chemistry, Portland State University, OR 97207
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30
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Picosecond absorbance changes upon selective excitation of the primary electron donor P-700 in Photosystem I. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 1986. [DOI: 10.1016/0005-2728(86)90187-8] [Citation(s) in RCA: 99] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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31
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Picosecond absorbance difference spectroscopy on the primary reactions and the antenna-excited states in Photosystem I particles. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 1986. [DOI: 10.1016/0005-2728(86)90186-6] [Citation(s) in RCA: 104] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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32
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Amesz J, Duysens LN. Electron donors and acceptors in photosynthetic reaction centers. PHOTOSYNTHESIS RESEARCH 1986; 10:337-346. [PMID: 24435381 DOI: 10.1007/bf00118299] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
A review is given of primary and associated electron transport reactions in various division of photosynthetic bacteria and in the two photosystems of plant photosynthesis. Two types of electron acceptor chains are distinguished: type 'Q', found in purple bacteria, Chloroflexus and system II of oxygenic photosynthesis and type 'F', found in green sulfur bacteria, Heliobacterium and photosystem I. Secondary donor reactions are discussed in relation to plant photosystem II.
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Affiliation(s)
- J Amesz
- Department of Biophysics, Huygens Laboratory of the State University, P.O. Box 9504, 2300 RA, Leiden, The Netherlands
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33
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Rutherford AW, Heathcote P. Primary photochemistry in photosystem-I. PHOTOSYNTHESIS RESEARCH 1985; 6:295-316. [PMID: 24442951 DOI: 10.1007/bf00054105] [Citation(s) in RCA: 81] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/13/1984] [Accepted: 01/31/1985] [Indexed: 06/03/2023]
Abstract
In this review, the main research developments that have led to the current simplified picture of photosystem I are presented. This is followed by a discussion of some conflicting reports and unresolved questions in the literature. The following points are made: (1) the evidence is contradictory on whether P700, the primary donor, is a monomer or dimer of chlorophyll although at this time the balacnce of the evidence points towards a monomeric structure for P700 when in the triplet state; (2) there is little evidence that the iron sulfur centers FA and FB act in series as tertiary acceptors and it is as likely that they act in parallel under physiological conditions; (3) a role for FX, probably another iron sulfur centrer, as an obligatory electron carrier in forward electron transfer has not been proven. Some evidence indicates that its reduction could represent a pathway different to that involving FA and FB; (4) the decay of the acceptor 'A2 (-)' as defined by optical spectroscopy corresponds with 700(+) % MathType!MTEF!2!1!+-% feaafeart1ev1aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn% hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr% 4rNCHbGeaGqiVu0Je9sqqrpepC0xbbL8F4rqqrFfpeea0xe9Lq-Jc9% vqaqpepm0xbba9pwe9Q8fs0-yqaqpepae9pg0FirpepeKkFr0xfr-x% fr-xb9adbaqaaeGaciGaaiaabeqaamaabaabaaGcbaGaamOramaaBa% aaleaadaqdaaqaaiaadIfaaaaabeaaaaa!37D1!\[F_{\overline X } \] recombination under some circumstances but under other conditions it probably corresponds with P700(+) A1 (-) recombination; (5) P700(+) A1 (-) recombination as originally observed by optical spectroscopy is probably due to the decay of the P700 triplet state; (6) the acceptor A1 (-) as defined by EPR may be a special semiquinone molecule; (7) A0 is probably a chlorophyll a molecule which acts as the primary acceptor. Recombination of P700(+) A0 (-) gives rise to the P700 triplet state.A working model for electron transfer in photosystem I is presented, its general features are discussed and comparisons with other photosystems are made.
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Affiliation(s)
- A W Rutherford
- Service de Biophysique, Department de Biologie, CEN Saclay, BP2, 91190, Gif sur Yvette, France
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Domain sizes in chloroplasts and chlorophyll-protein complexes probed by fluorescence yield quenching induced by singlet-triplet exciton annihilation. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 1985. [DOI: 10.1016/0005-2728(85)90028-3] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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35
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Il'ina MD, Krasauskas VV, Rotomskis RJ, Borisov AY. Difference picosecond spectroscopy of pigment-protein complexes of photosystem I from higher plants. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 1984. [DOI: 10.1016/0005-2728(84)90048-3] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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Abstract
Photosynthesis is the conversion of the quantum energy of light into the chemical energy of complex organic molecules and organized cellular structures in plants and in some bacteria. The processes of photosynthesis span the time domain of subpicoseconds to the millennia of slow-growing trees, its study brings together such diverse disciplines as photophysics, biochemistry, botany and ecology. In the last few decades tremendous progress has been made in understanding the multivarious chemical reactions that ultimately lead to the fixation of carbon dioxide into organic substance, yet the basic mechanism underlying the conversion of photon energy into chemical energy still remains very much an enigma. These so-called primary reactions which transduce the excitation energy of excited chlorophyll pigments into the potential energy of stabilized, separated charges on electron donor and electron acceptor molecules have been studied with a variety of physical techniques, among which fast optical spectroscopy and electron paramagnetic resonance (EPR) are prominent. This review will highlight one intriguing aspect of EPR, namely that of electron spin polarization (ESP).† It will be shown that ESP of photosynthetic primary reactants offers a unique tool to gain insight in the electrostatic and magnetic interactions that make photosynthesis work. Moreover, it will become apparent that ESP in photosynthesis has several unique traits not (yet) found in ESP of photochemical reactionsin vitro. As such, it may serve as a paradigma of ESP phenomena and will present an absorbing spectacle also for EPR spectroscopists outside photosynthesis.
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38
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Manikowski H, McIntosh AR, Bolton JR. A study of chemically induced dynamic electron polarization (CIDEP) in Photosystem I of whole algal cells at ambient temperatures. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 1984. [DOI: 10.1016/0005-2728(84)90158-0] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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Ikegami I, Ke B. A 160-kilodalton Photosystem-I reaction-center complex. Low-temperature absorption and EPR spectroscopy of the early electron acceptors. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 1984. [DOI: 10.1016/0005-2728(84)90142-7] [Citation(s) in RCA: 34] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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Abstract
A theory of the excitation kinetics in the bacteria photosynthetic unit with regard to its globular structure is presented. It assumes that the excitation transfer between globulae is carried out by means of the mechanism of incoherent excitons, at the same time considering the finite time of the excitation fixation in the reaction center. A method of local perturbations is used with a view to finding a solution to the given problem. The expressions obtained for the fluorescence decay time and its quantum yield are discussed in connection with the multiple experiments considering the cubic as well as the hexagonal probable structure of the photosynthetic unit. The analysis given shows that the period of the excitation transfer between globulae equals 10 to 100 psec and the number of the globulae is less than 35. These conclusions fall in with the initial assumption of the energy transfer between globulae by incoherent excitons. Without considering the globularity, the consistency of the theory with experimental data becomes difficult.
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41
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Kamogawa K, Morris JM, Takagi Y, Nakashima N, Yoshihara K, Ikegami I. PICOSECOND FLUORESCENCE STUDIES OF P700-ENRICHED PARTICLES OF SPINACH CHLOROPLASTS. Photochem Photobiol 1983. [DOI: 10.1111/j.1751-1097.1983.tb04460.x] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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Gast P, Swarthoff T, Ebskamp F, Hoff A. Evidence for a new early acceptor in Photosystem I of plants. An ESR investigation of reaction center triplet yield and of the reduced intermediary acceptors. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 1983. [DOI: 10.1016/0005-2728(83)90170-6] [Citation(s) in RCA: 69] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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Crowder MS, Bearden A. Primary photochemistry of Photosystem I in chloroplasts. Dynamics of reversible charge separation in open reaction centers at 25 K. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 1983. [DOI: 10.1016/0005-2728(83)90153-6] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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Thurnauer M, Rutherford A, Norris J. The effect of ambient redox potential on the transient electron spin echo signals observed in chloroplasts and photosynthetic algae. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 1982. [DOI: 10.1016/0005-2728(82)90046-9] [Citation(s) in RCA: 37] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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45
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Petke JD, Maggiora GM, Shipman LL, Christoffersen RE. STEREOELECTRONIC PROPERTIES OF PHOTOSYNTHETIC AND RELATED SYSTEMS. XI. AB INITIO QUANTUM MECHANICAL CHARACTERIZATION OF THE ELECTRONIC STRUCTURE AND SPECTRA OF THE CHLOROPHYLLIDE a AND PHEOPHORBIDE a ANION RADICALS. Photochem Photobiol 1982. [DOI: 10.1111/j.1751-1097.1982.tb04391.x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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46
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Primary processes in Photosystem I. Identification and decay kinetics of the P-700 triplet state. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 1982. [DOI: 10.1016/0005-2728(82)90174-8] [Citation(s) in RCA: 25] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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47
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The yield of chlorophyll a fluorescence as a means to test the various deexcitation mechanisms in the antenna system of green plants. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 1982. [DOI: 10.1016/0005-2728(82)90273-0] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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48
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Junge W. Chapter 24 Electrogenic Reactions and Proton Pumping in Green Plant Photosynthesis. CURRENT TOPICS IN MEMBRANES AND TRANSPORT 1982. [DOI: 10.1016/s0070-2161(08)60714-5] [Citation(s) in RCA: 38] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
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49
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Flash-induced absorption changes in Photosystem I, Radical pair or triplet state formation? BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 1981. [DOI: 10.1016/0005-2728(81)90235-8] [Citation(s) in RCA: 64] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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Abstract
When light impinges on photosynthetic material – a plant leaf, an alga or a photosynthetic bacterium – it is absorbed by an array of lightcollecting pigments. Through resonant energy transfer the absorbed quantum of light is transported to a trap, the reaction centre. Within such a trap, a specialized (bacterio)chlorophyll complex is able to eject from its excited state an electron. This electron is ‘captured’ by an adjacent acceptor, which in turn donates the electron to a second acceptor, and so on. Thus, light energy is converted into chemical energy which is ultimately used in the metabolic processes of the cell.
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