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Cherepanov DA, Kurashov V, Gostev FE, Shelaev IV, Zabelin AA, Shen G, Mamedov MD, Aybush A, Shkuropatov AY, Nadtochenko VA, Bryant DA, Golbeck JH, Semenov AY. Femtosecond optical studies of the primary charge separation reactions in far-red photosystem II from Synechococcus sp. PCC 7335. BIOCHIMICA ET BIOPHYSICA ACTA. BIOENERGETICS 2024; 1865:149044. [PMID: 38588942 DOI: 10.1016/j.bbabio.2024.149044] [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: 09/22/2023] [Revised: 01/26/2024] [Accepted: 04/02/2024] [Indexed: 04/10/2024]
Abstract
Primary processes of light energy conversion by Photosystem II (PSII) were studied using femtosecond broadband pump-probe absorption difference spectroscopy. Transient absorption changes of core complexes isolated from the cyanobacterium Synechococcus sp. PCC 7335 grown under far-red light (FRL-PSII) were compared with the canonical Chl a containing spinach PSII core complexes upon excitation into the red edge of the Qy band. Absorption changes of FRL-PSII were monitored at 278 K in the 400-800 nm spectral range on a timescale of 0.1-500 ps upon selective excitation at 740 nm of four chlorophyll (Chl) f molecules in the light harvesting antenna, or of one Chl d molecule at the ChlD1 position in the reaction center (RC) upon pumping at 710 nm. Numerical analysis of absorption changes and assessment of the energy levels of the presumed ion-radical states made it possible to identify PD1+ChlD1- as the predominant primary charge-separated radical pair, the formation of which upon selective excitation of Chl d has an apparent time of ∼1.6 ps. Electron transfer to the secondary acceptor pheophytin PheoD1 has an apparent time of ∼7 ps with a variety of excitation wavelengths. The energy redistribution between Chl a and Chl f in the antenna occurs within 1 ps, whereas the energy migration from Chl f to the RC occurs mostly with lifetimes of 60 and 400 ps. Potentiometric analysis suggests that in canonical PSII, PD1+ChlD1- can be partially formed from the excited (PD1ChlD1)* state.
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Affiliation(s)
- Dmitry A Cherepanov
- N.N. Semenov Federal Research Center for Chemical Physics, Russian Academy of Sciences, Kosygina st., 4, 119991 Moscow, Russia; A.N. Belozersky Institute of Physical-Chemical Biology, Lomonosov Moscow State University, Leninskiye Gory, 1, building 40, 119992 Moscow, Russia.
| | - Vasily Kurashov
- Department of Biochemistry and Molecular Biology, The Pennsylvania State University, University Park, 16802, USA
| | - Fedor E Gostev
- N.N. Semenov Federal Research Center for Chemical Physics, Russian Academy of Sciences, Kosygina st., 4, 119991 Moscow, Russia
| | - Ivan V Shelaev
- N.N. Semenov Federal Research Center for Chemical Physics, Russian Academy of Sciences, Kosygina st., 4, 119991 Moscow, Russia
| | - Alexey A Zabelin
- Institute of Basic Biological Problems of the Russian Academy of Sciences, Federal Research Center "Pushchino Scientific Center for Biological Research of the Russian Academy of Sciences", 142290 Pushchino, Moscow Region, Russia
| | - Gaozhong Shen
- Department of Biochemistry and Molecular Biology, The Pennsylvania State University, University Park, 16802, USA
| | - Mahir D Mamedov
- A.N. Belozersky Institute of Physical-Chemical Biology, Lomonosov Moscow State University, Leninskiye Gory, 1, building 40, 119992 Moscow, Russia
| | - Arseny Aybush
- N.N. Semenov Federal Research Center for Chemical Physics, Russian Academy of Sciences, Kosygina st., 4, 119991 Moscow, Russia
| | - Anatoly Ya Shkuropatov
- Institute of Basic Biological Problems of the Russian Academy of Sciences, Federal Research Center "Pushchino Scientific Center for Biological Research of the Russian Academy of Sciences", 142290 Pushchino, Moscow Region, Russia
| | - Victor A Nadtochenko
- N.N. Semenov Federal Research Center for Chemical Physics, Russian Academy of Sciences, Kosygina st., 4, 119991 Moscow, Russia; Chemistry Department, Lomonosov Moscow State University, Leninskiye Gory, 1, 119991 Moscow, Russia
| | - Donald A Bryant
- Department of Biochemistry and Molecular Biology, The Pennsylvania State University, University Park, 16802, USA
| | - John H Golbeck
- Department of Biochemistry and Molecular Biology, The Pennsylvania State University, University Park, 16802, USA; Department of Chemistry, The Pennsylvania State University, University Park, 16802, USA
| | - Alexey Yu Semenov
- N.N. Semenov Federal Research Center for Chemical Physics, Russian Academy of Sciences, Kosygina st., 4, 119991 Moscow, Russia; A.N. Belozersky Institute of Physical-Chemical Biology, Lomonosov Moscow State University, Leninskiye Gory, 1, building 40, 119992 Moscow, Russia.
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Jha A, Zhang PP, Tiwari V, Chen L, Thorwart M, Miller RJD, Duan HG. Unraveling quantum coherences mediating primary charge transfer processes in photosystem II reaction center. SCIENCE ADVANCES 2024; 10:eadk1312. [PMID: 38446882 PMCID: PMC10917350 DOI: 10.1126/sciadv.adk1312] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/03/2023] [Accepted: 01/31/2024] [Indexed: 03/08/2024]
Abstract
Photosystem II (PSII) reaction center (RC) is a unique complex that is capable of efficiently separating electronic charges across the membrane. The primary energy- and charge-transfer (CT) processes occur on comparable ultrafast timescales, which makes it extremely challenging to understand the fundamental mechanism responsible for the near-unity quantum efficiency of the transfer. Here, we elucidate the role of quantum coherences in the ultrafast energy and CT in the PSII RC by performing two-dimensional (2D) electronic spectroscopy at the cryogenic temperature of 20 kelvin, which captures the distinct underlying quantum coherences. Specifically, we uncover the electronic and vibrational coherences along with their lifetimes during the primary ultrafast processes of energy and CT. We construct an excitonic model that provides evidence for coherent energy and CT at low temperature in the 2D electronic spectra. The principles could provide valuable guidelines for creating artificial photosystems with exploitation of system-bath coupling and control of coherences to optimize the photon conversion efficiency to specific functions.
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Affiliation(s)
- Ajay Jha
- Department of Physics, School of Physical Science and Technology, Ningbo University, Ningbo, 315211, P.R. China
- Max Planck Institute for the Structure and Dynamics of Matter, Luruper Chaussee 149, 22761, Hamburg, Germany
- Rosalind Franklin Institute, Harwell, Oxfordshire OX11 0QX, UK
- Department of Pharmacology, University of Oxford, Oxford OX1 3QT, UK
| | - Pan-Pan Zhang
- Department of Physics, School of Physical Science and Technology, Ningbo University, Ningbo, 315211, P.R. China
| | - Vandana Tiwari
- Max Planck Institute for the Structure and Dynamics of Matter, Luruper Chaussee 149, 22761, Hamburg, Germany
- Department of Chemistry, University of Hamburg, Martin-Luther-King Platz 6, 20146 Hamburg, Germany
| | - Lipeng Chen
- Zhejiang Laboratory, Hangzhou 311100, P.R. China
| | - Michael Thorwart
- I. Institut für Theoretische Physik, Universität Hamburg, Notkestr. 9, 22607 Hamburg, Germany
- The Hamburg Center for Ultrafast Imaging, Luruper Chaussee 149, 22761 Hamburg, Germany
| | - R. J. Dwayne Miller
- The Departments of Chemistry and Physics, University of Toronto, 80 St. George Street, Toronto, ON M5S 3H6, Canada
| | - Hong-Guang Duan
- Department of Physics, School of Physical Science and Technology, Ningbo University, Ningbo, 315211, P.R. China
- Max Planck Institute for the Structure and Dynamics of Matter, Luruper Chaussee 149, 22761, Hamburg, Germany
- I. Institut für Theoretische Physik, Universität Hamburg, Notkestr. 9, 22607 Hamburg, Germany
- The Hamburg Center for Ultrafast Imaging, Luruper Chaussee 149, 22761 Hamburg, Germany
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3
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Agostini A, Shen G, Bryant DA, Golbeck JH, van der Est A, Carbonera D. Optically detected magnetic resonance and mutational analysis reveal significant differences in the photochemistry and structure of chlorophyll f synthase and photosystem II. BIOCHIMICA ET BIOPHYSICA ACTA. BIOENERGETICS 2023; 1864:149002. [PMID: 37562512 DOI: 10.1016/j.bbabio.2023.149002] [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: 05/29/2023] [Revised: 07/24/2023] [Accepted: 07/31/2023] [Indexed: 08/12/2023]
Abstract
In cyanobacteria that undergo far red light photoacclimation (FaRLiP), chlorophyll (Chl) f is produced by the ChlF synthase enzyme, probably by photo-oxidation of Chl a. The enzyme forms homodimeric complexes and the primary amino acid sequence of ChlF shows a high degree of homology with the D1 subunit of photosystem II (PSII). However, few details of the photochemistry of ChlF are known. The results of a mutational analysis and optically detected magnetic resonance (ODMR) data from ChlF are presented. Both sets of data show that there are significant differences in the photochemistry of ChlF and PSII. Mutation of residues that would disrupt the donor side primary electron transfer pathway in PSII do not inhibit the production of Chl f, while alteration of the putative ChlZ, P680 and QA binding sites rendered ChlF non-functional. Together with previously published transient EPR and flash photolysis data, the ODMR data show that in untreated ChlF samples, the triplet state of P680 formed by intersystem crossing is the primary species generated by light excitation. This is in contrast to PSII, in which 3P680 is only formed by charge recombination when the quinone acceptors are removed or chemically reduced. The triplet states of a carotenoid (3Car) and a small amount of 3Chl f are also observed by ODMR. The polarization pattern of 3Car is consistent with its formation by triplet energy transfer from ChlZ if the carotenoid molecule is rotated by 15° about its long axis compared to the orientation in PSII. It is proposed that the singlet oxygen formed by the interaction between molecular oxygen and 3P680 might be involved in the oxidation of Chl a to Chl f.
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Affiliation(s)
- Alessandro Agostini
- Department of Chemical Sciences, University of Padova, Via Marzolo, 1, 35131, Padova, Italy; Biology Centre, Czech Academy of Sciences, Institute of Plant Molecular Biology, Branišovská 31, 370 05 Ceske Budejovice, Czech Republic
| | - Gaozhong Shen
- Department of Biochemistry and Molecular Biology, The Pennsylvania State University, University Park, 16802, USA
| | - Donald A Bryant
- Department of Biochemistry and Molecular Biology, The Pennsylvania State University, University Park, 16802, USA
| | - John H Golbeck
- Department of Biochemistry and Molecular Biology, The Pennsylvania State University, University Park, 16802, USA; Department of Chemistry, The Pennsylvania State University, University Park, 16802, USA
| | - Art van der Est
- Department of Chemistry, Brock University, 1812 Sir Isaac Brock, Way, St. Catharines, ON L2S 3A1, Canada.
| | - Donatella Carbonera
- Department of Chemical Sciences, University of Padova, Via Marzolo, 1, 35131, Padova, Italy.
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Nguyen HH, Song Y, Maret EL, Silori Y, Willow R, Yocum CF, Ogilvie JP. Charge separation in the photosystem II reaction center resolved by multispectral two-dimensional electronic spectroscopy. SCIENCE ADVANCES 2023; 9:eade7190. [PMID: 37134172 PMCID: PMC10156117 DOI: 10.1126/sciadv.ade7190] [Citation(s) in RCA: 12] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/05/2023]
Abstract
The photosystem II reaction center (PSII RC) performs the primary energy conversion steps of oxygenic photosynthesis. While the PSII RC has been studied extensively, the similar time scales of energy transfer and charge separation and the severely overlapping pigment transitions in the Qy region have led to multiple models of its charge separation mechanism and excitonic structure. Here, we combine two-dimensional electronic spectroscopy (2DES) with a continuum probe and two-dimensional electronic vibrational spectroscopy (2DEV) to study the cyt b559-D1D2 PSII RC at 77 K. This multispectral combination correlates the overlapping Qy excitons with distinct anion and pigment-specific Qx and mid-infrared transitions to resolve the charge separation mechanism and excitonic structure. Through extensive simultaneous analysis of the multispectral 2D data, we find that charge separation proceeds on multiple time scales from a delocalized excited state via a single pathway in which PheoD1 is the primary electron acceptor, while ChlD1 and PD1 act in concert as the primary electron donor.
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Affiliation(s)
- Hoang H Nguyen
- Department of Physics and Biophysics, University of Michigan, 450 Church St., Ann Arbor, MI 48109, USA
| | - Yin Song
- Department of Physics and Biophysics, University of Michigan, 450 Church St., Ann Arbor, MI 48109, USA
- School of Optics and Photonics, Beijing Institute of Technology, 5 Zhongguancun South Street, Haidian District, Beijing, 100081, China
| | - Elizabeth L Maret
- Department of Physics and Biophysics, University of Michigan, 450 Church St., Ann Arbor, MI 48109, USA
| | - Yogita Silori
- Department of Physics and Biophysics, University of Michigan, 450 Church St., Ann Arbor, MI 48109, USA
| | - Rhiannon Willow
- Department of Physics and Biophysics, University of Michigan, 450 Church St., Ann Arbor, MI 48109, USA
| | - Charles F Yocum
- Department of Molecular, Cellular and Developmental Biology and Department of Chemistry, University of Michigan, 450 Church St, Ann Arbor, MI 48109, USA
| | - Jennifer P Ogilvie
- Department of Physics and Biophysics, University of Michigan, 450 Church St., Ann Arbor, MI 48109, USA
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5
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Çakıroğlu B, Jabiyeva N, Holzinger M. Photosystem II as a chemiluminescence-induced photosensitizer for photoelectrochemical biofuel cell-type biosensing system. Biosens Bioelectron 2023; 226:115133. [PMID: 36773487 DOI: 10.1016/j.bios.2023.115133] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2022] [Revised: 01/31/2023] [Accepted: 02/06/2023] [Indexed: 02/11/2023]
Abstract
Herein, photosystem II (PSII), extracted from spinach, is used for the first time as an efficient and green sensitizer for a photobioanode in a photoelectrochemical glucose biofuel cell (PBFC) setup. The concept is based on the formation of hemin-catalyzed luminol chemiluminescence (CL) after the enzymatic oxidation of glucose and the simultaneous production of hydrogen peroxide by glucose oxidase. The photosynthetic enzyme PSII, combined with an osmium polymer serving as mediator and photosensitizer, is immobilized and wired on microporous carbonaceous material (MC) for the chemiluminescence-induced oxidation of water to O2 at the photobioanode (GCE|MC|Os polymer|PSII). Also, bilirubin oxidase immobilized on multiwalled carbon nanotubes (MWCNTs) coated electrode (GCE|MWCNT|BOx) serves as a biocathode. The photoelectrochemical biofuel cell (PBFC) is applied to a biosensor model system to validate the appropriateness of such a bioanode operating in a self-powered mode. Os redox polymer attached to MCs provides abundant PSII immobilization and a reliable electron transfer pathway. The well-matching energy levels of photosensitive entities reduce recombination phenomena while MC enhances the charge collection. Substantial photocatalytic water oxidation was observed under CL due to the well-matched CL emission and PSII absorption. The electrode is rationally designed to gain the maximum luminol CL power for the photobioanode. The open circuit potential of PBFC linearly increased with the CL power intensity and, in turn, glucose concentrations in the range of 0-6 mmol L-1. The PBFC yielded an OCP of 0.531 V in 30 mmolL-1 glucose. The study may open a new horizon to the green and pioneering PEC biosensing realm.
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Affiliation(s)
- Bekir Çakıroğlu
- Université Grenoble Alpes, DCM UMR 5250, F-38000, Grenoble, France; Sakarya University, Biomedical, Magnetic and Semiconductor Materials Research Center (BIMAS-RC), 54187, Sakarya, Turkey.
| | - Naiba Jabiyeva
- Université Grenoble Alpes, DCM UMR 5250, F-38000, Grenoble, France; Sakarya University, Science & Arts Faculty, Department of Chemistry, 54187, Sakarya, Turkey
| | - Michael Holzinger
- Université Grenoble Alpes, DCM UMR 5250, F-38000, Grenoble, France; CNRS, DCM UMR 5250, F-38000, Grenoble, France.
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6
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Niklas J, Agostini A, Carbonera D, Di Valentin M, Lubitz W. Primary donor triplet states of Photosystem I and II studied by Q-band pulse ENDOR spectroscopy. PHOTOSYNTHESIS RESEARCH 2022; 152:213-234. [PMID: 35290567 PMCID: PMC9424170 DOI: 10.1007/s11120-022-00905-y] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/01/2021] [Accepted: 02/14/2022] [Indexed: 05/05/2023]
Abstract
The photoexcited triplet state of the "primary donors" in the two photosystems of oxygenic photosynthesis has been investigated by means of electron-nuclear double resonance (ENDOR) at Q-band (34 GHz). The data obtained represent the first set of 1H hyperfine coupling tensors of the 3P700 triplet state in PSI and expand the existing data set for 3P680. We achieved an extensive assignment of the observed electron-nuclear hyperfine coupling constants (hfcs) corresponding to the methine α-protons and the methyl group β-protons of the chlorophyll (Chl) macrocycle. The data clearly confirm that in both photosystems the primary donor triplet is located on one specific monomeric Chl at cryogenic temperature. In comparison to previous transient ENDOR and pulse ENDOR experiments at standard X-band (9-10 GHz), the pulse Q-band ENDOR spectra demonstrate both improved signal-to-noise ratio and increased resolution. The observed ENDOR spectra for 3P700 and 3P680 differ in terms of the intensity loss of lines from specific methyl group protons, which is explained by hindered methyl group rotation produced by binding site effects. Contact analysis of the methyl groups in the PSI crystal structure in combination with the ENDOR analysis of 3P700 suggests that the triplet is located on the Chl a' (PA) in PSI. The results also provide additional evidence for the localization of 3P680 on the accessory ChlD1 in PSII.
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Affiliation(s)
- Jens Niklas
- Max Planck Institute for Chemical Energy Conversion, Stiftstrasse 34-36, 45470, Mülheim an der Ruhr, Germany.
- Chemical Sciences and Engineering Division, Argonne National Laboratory, 9700 S. Cass Ave., Lemont, IL, 60439, USA.
| | - Alessandro Agostini
- Department of Chemical Sciences, University of Padova, via Marzolo 1, 35131, Padova, Italy
- Biology Centre, Institute of Plant Molecular Biology, Czech Academy of Sciences, Branišovská 31, 370 05, Ceske Budejovice, Czech Republic
| | - Donatella Carbonera
- Department of Chemical Sciences, University of Padova, via Marzolo 1, 35131, Padova, Italy
| | - Marilena Di Valentin
- Department of Chemical Sciences, University of Padova, via Marzolo 1, 35131, Padova, Italy.
| | - Wolfgang Lubitz
- Max Planck Institute for Chemical Energy Conversion, Stiftstrasse 34-36, 45470, Mülheim an der Ruhr, Germany.
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Baituti B, Odisitse S. A Computational Study of the S 2 State in the Oxygen-Evolving Complex of Photosystem II by Electron Paramagnetic Resonance Spectroscopy. Molecules 2021; 26:2699. [PMID: 34064533 PMCID: PMC8125536 DOI: 10.3390/molecules26092699] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2021] [Revised: 04/22/2021] [Accepted: 04/24/2021] [Indexed: 11/16/2022] Open
Abstract
The S2 state produces two basic electron paramagnetic resonance signal types due to the manganese cluster in oxygen-evolving complex, which are influenced by the solvents, and cryoprotectant added to the photosystem II samples. It is presumed that a single manganese center oxidation occurs on S1 → S2 state transition. The S2 state has readily visible multiline and g4.1 electron paramagnetic resonance signals and hence it has been the most studied of all the Kok cycle intermediates due to the ease of experimental preparation and stability. The S2 state was studied using electron paramagnetic resonance spectroscopy at X-band frequencies. The aim of this study was to determine the spin states of the g4.1 signal. The multiline signal was observed to arise from a ground state spin ½ centre while the g4.1 signal generated at ≈140 K NIR illumination was proposed to arise from a spin 52 center with rhombic distortion. The 'ground' state g4.1 signal was generated solely or by conversion from the multiline. The data analysis methods used involved numerical simulations of the experimental spectra on relevant models of the oxygen-evolving complex cluster. A strong focus in this paper was on the 'ground' state g4.1 signal, whether it is a rhombic 52 spin state signal or an axial 32 spin state signal. The data supported an X-band CW-EPR-generated g4.1 signal as originating from a near rhombic spin 5/2 of the S2 state of the PSII manganese cluster.
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Affiliation(s)
- Bernard Baituti
- Department of Chemical and Forensic Science, Faculty of Science, Botswana International University of Science and Technology, Private Bag 16, Palapye, Botswana;
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Ostroumov EE, Götze JP, Reus M, Lambrev PH, Holzwarth AR. Characterization of fluorescent chlorophyll charge-transfer states as intermediates in the excited state quenching of light-harvesting complex II. PHOTOSYNTHESIS RESEARCH 2020; 144:171-193. [PMID: 32307623 DOI: 10.1007/s11120-020-00745-8] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/02/2020] [Accepted: 03/31/2020] [Indexed: 05/20/2023]
Abstract
Light-harvesting complex II (LHCII) is the major antenna complex in higher plants and green algae. It has been suggested that a major part of the excited state energy dissipation in the so-called "non-photochemical quenching" (NPQ) is located in this antenna complex. We have performed an ultrafast kinetics study of the low-energy fluorescent states related to quenching in LHCII in both aggregated and the crystalline form. In both sample types the chlorophyll (Chl) excited states of LHCII are strongly quenched in a similar fashion. Quenching is accompanied by the appearance of new far-red (FR) fluorescence bands from energetically low-lying Chl excited states. The kinetics of quenching, its temperature dependence down to 4 K, and the properties of the FR-emitting states are very similar both in LHCII aggregates and in the crystal. No such FR-emitting states are found in unquenched trimeric LHCII. We conclude that these states represent weakly emitting Chl-Chl charge-transfer (CT) states, whose formation is part of the quenching process. Quantum chemical calculations of the lowest energy exciton and CT states, explicitly including the coupling to the specific protein environment, provide detailed insight into the chemical nature of the CT states and the mechanism of CT quenching. The experimental data combined with the results of the calculations strongly suggest that the quenching mechanism consists of a sequence of two proton-coupled electron transfer steps involving the three quenching center Chls 610/611/612. The FR-emitting CT states are reaction intermediates in this sequence. The polarity-controlled internal reprotonation of the E175/K179 aa pair is suggested as the switch controlling quenching. A unified model is proposed that is able to explain all known conditions of quenching or non-quenching of LHCII, depending on the environment without invoking any major conformational changes of the protein.
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Affiliation(s)
- Evgeny E Ostroumov
- Max-Planck-Institut für Chemische Energiekonversion, Stiftstrasse 34-36, 45470, Mülheim a. d. Ruhr, Germany
- Quantum Matter Institute, University of British Columbia, 2355 East Mall, Vancouver, V6T 1Z1, Canada
| | - Jan P Götze
- Max-Planck-Institut für Chemische Energiekonversion, Stiftstrasse 34-36, 45470, Mülheim a. d. Ruhr, Germany
- Institut für Chemie und Biochemie, Freie Universität Berlin, Arnimallee 22, 14195, Berlin, Germany
| | - Michael Reus
- Max-Planck-Institut für Chemische Energiekonversion, Stiftstrasse 34-36, 45470, Mülheim a. d. Ruhr, Germany
| | - Petar H Lambrev
- Biological Research Centre, Temesvári krt. 62, Szeged, 6726, Hungary
| | - Alfred R Holzwarth
- Max-Planck-Institut für Chemische Energiekonversion, Stiftstrasse 34-36, 45470, Mülheim a. d. Ruhr, Germany.
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9
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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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10
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Janssen GJ, Bielytskyi P, Artiukhin DG, Neugebauer J, de Groot HJM, Matysik J, Alia A. Photochemically induced dynamic nuclear polarization NMR on photosystem II: donor cofactor observed in entire plant. Sci Rep 2018; 8:17853. [PMID: 30552342 PMCID: PMC6294776 DOI: 10.1038/s41598-018-36074-z] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2018] [Accepted: 11/13/2018] [Indexed: 12/18/2022] Open
Abstract
The solid-state photo-CIDNP (photochemically induced dynamic nuclear polarization) effect allows for increase of signal and sensitivity in magic-angle spinning (MAS) NMR experiments. The effect occurs in photosynthetic reaction centers (RC) proteins upon illumination and induction of cyclic electron transfer. Here we show that the strength of the effect allows for observation of the cofactors forming the spin-correlated radical pair (SCRP) in isolated proteins, in natural photosynthetic membranes as well as in entire plants. To this end, we measured entire selectively 13C isotope enriched duckweed plants (Spirodela oligorrhiza) directly in the MAS rotor. Comparison of 13C photo-CIDNP MAS NMR spectra of photosystem II (PS2) obtained from different levels of RC isolation, from entire plant to isolated RC complex, demonstrates the intactness of the photochemical machinery upon isolation. The SCRP in PS2 is structurally and functionally very similar in duckweed and spinach (Spinacia oleracea). The analysis of the photo-CIDNP MAS NMR spectra reveals a monomeric Chl a donor. There is an experimental evidence for matrix involvement, most likely due to the axial donor histidine, in the formation of the SCRP. Data do not suggest a chemical modification of C-131 carbonyl position of the donor cofactor.
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Affiliation(s)
- Geertje J Janssen
- University of Leiden, Leiden Institute of Chemistry, Einsteinweg 55, P.O. Box 9502, 2300 RA, Leiden, The Netherlands
| | - Pavlo Bielytskyi
- Universität Leipzig, Institute of Analytical Chemistry, Johannisallee 29, D-04103, Leipzig, Germany
| | - Denis G Artiukhin
- Westfälische Wilhelms-Universität Münster, Organisch-Chemisches Institut and Center for Multiscale Theory and Computation, Corrensstraße 40, D-48149, Münster, Germany
| | - Johannes Neugebauer
- Westfälische Wilhelms-Universität Münster, Organisch-Chemisches Institut and Center for Multiscale Theory and Computation, Corrensstraße 40, D-48149, Münster, Germany
| | - Huub J M de Groot
- University of Leiden, Leiden Institute of Chemistry, Einsteinweg 55, P.O. Box 9502, 2300 RA, Leiden, The Netherlands
| | - Jörg Matysik
- Universität Leipzig, Institute of Analytical Chemistry, Johannisallee 29, D-04103, Leipzig, Germany.
| | - A Alia
- University of Leiden, Leiden Institute of Chemistry, Einsteinweg 55, P.O. Box 9502, 2300 RA, Leiden, The Netherlands.
- Universität Leipzig, Institute of Medical Physics and Biophysics, Härtelstr. 16-18, D-04107, Leipzig, Germany.
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11
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Li Y, Fei J, Li G, Xie H, Yang Y, Li J, Xu Y, Sun B, Xia J, Fu X, Li J. Supramolecular Assembly of Photosystem II and Adenosine Triphosphate Synthase in Artificially Designed Honeycomb Multilayers for Photophosphorylation. ACS NANO 2018; 12:1455-1461. [PMID: 29361225 DOI: 10.1021/acsnano.7b07841] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Plant thylakoids have a typical stacking structure, which is the site of photosynthesis, including light-harvesting, water-splitting, and adenosine triphosphate (ATP) production. This stacking structure plays a key role in exchange of substances with extremely high efficiency and minimum energy consumption through photosynthesis. Herein we report an artificially designed honeycomb multilayer for photophosphorylation. To mimic the natural thylakoid stacking structure, the multilayered photosystem II (PSII)-ATP synthase-liposome system is fabricated via layer-by-layer (LbL) assembly, allowing the three-dimensional distributions of PSII and ATP synthase. Under light illumination, PSII splits water into protons and generates a proton gradient for ATP synthase to produce ATP. Moreover, it is found that the ATP production is extremely associated with the numbers of PSII layers. With such a multilayer structure assembled via LbL, one can better understand the mechanism of PSII and ATP synthase integrated in one system, mimicking the photosynthetic grana structure. On the other hand, such an assembled system can be considered to improve the photophosphorylation.
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Affiliation(s)
- Yue Li
- Beijing National Laboratory for Molecular Sciences, CAS Key Laboratory of Colloid, Interface and Chemical Thermodynamics, Institute of Chemistry, Chinese Academy of Sciences , Beijing 100190, China
- CAS Key Laboratory for Biomedical Effects of Nanomaterials and Nanosafety, National Center for Nanoscience and Technology , Beijing 100190, China
- College of Life Science, Jilin University , Changchun 130012, China
| | - Jinbo Fei
- Beijing National Laboratory for Molecular Sciences, CAS Key Laboratory of Colloid, Interface and Chemical Thermodynamics, Institute of Chemistry, Chinese Academy of Sciences , Beijing 100190, China
| | - Guangle Li
- Beijing National Laboratory for Molecular Sciences, CAS Key Laboratory of Colloid, Interface and Chemical Thermodynamics, Institute of Chemistry, Chinese Academy of Sciences , Beijing 100190, China
- University of Chinese Academic of Sciences , Beijing 100049, China
| | - Haiming Xie
- National & Local United Engineering Laboratory for Power Battery, Department of Chemistry, Northeast Normal University , Changchun 130024, China
| | - Yang Yang
- CAS Key Laboratory for Biomedical Effects of Nanomaterials and Nanosafety, National Center for Nanoscience and Technology , Beijing 100190, China
| | - Jieling Li
- Beijing National Laboratory for Molecular Sciences, CAS Key Laboratory of Colloid, Interface and Chemical Thermodynamics, Institute of Chemistry, Chinese Academy of Sciences , Beijing 100190, China
| | - Youqian Xu
- Beijing National Laboratory for Molecular Sciences, CAS Key Laboratory of Colloid, Interface and Chemical Thermodynamics, Institute of Chemistry, Chinese Academy of Sciences , Beijing 100190, China
- University of Chinese Academic of Sciences , Beijing 100049, China
| | - Bingbing Sun
- Beijing National Laboratory for Molecular Sciences, CAS Key Laboratory of Colloid, Interface and Chemical Thermodynamics, Institute of Chemistry, Chinese Academy of Sciences , Beijing 100190, China
- University of Chinese Academic of Sciences , Beijing 100049, China
| | - Jiarui Xia
- Beijing National Laboratory for Molecular Sciences, CAS Key Laboratory of Colloid, Interface and Chemical Thermodynamics, Institute of Chemistry, Chinese Academy of Sciences , Beijing 100190, China
- University of Chinese Academic of Sciences , Beijing 100049, China
| | - Xueqi Fu
- College of Life Science, Jilin University , Changchun 130012, China
| | - Junbai Li
- Beijing National Laboratory for Molecular Sciences, CAS Key Laboratory of Colloid, Interface and Chemical Thermodynamics, Institute of Chemistry, Chinese Academy of Sciences , Beijing 100190, China
- University of Chinese Academic of Sciences , Beijing 100049, China
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12
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Gelzinis A, Abramavicius D, Ogilvie JP, Valkunas L. Spectroscopic properties of photosystem II reaction center revisited. J Chem Phys 2017; 147:115102. [DOI: 10.1063/1.4997527] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Affiliation(s)
- Andrius Gelzinis
- Department of Theoretical Physics, Faculty of Physics, Vilnius University, Sauletekio 9-III, 10222 Vilnius, Lithuania
- Department of Molecular Compound Physics, Center for Physical Sciences and Technology, Sauletekio 3, 10257 Vilnius, Lithuania
| | - Darius Abramavicius
- Department of Theoretical Physics, Faculty of Physics, Vilnius University, Sauletekio 9-III, 10222 Vilnius, Lithuania
| | - Jennifer P. Ogilvie
- Department of Physics, University of Michigan, Ann Arbor, Michigan 48109, USA
| | - Leonas Valkunas
- Department of Theoretical Physics, Faculty of Physics, Vilnius University, Sauletekio 9-III, 10222 Vilnius, Lithuania
- Department of Molecular Compound Physics, Center for Physical Sciences and Technology, Sauletekio 3, 10257 Vilnius, Lithuania
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13
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Zhang JZ, Sokol KP, Paul N, Romero E, van Grondelle R, Reisner E. Competing charge transfer pathways at the photosystem II-electrode interface. Nat Chem Biol 2016; 12:1046-1052. [PMID: 27723748 PMCID: PMC5113757 DOI: 10.1038/nchembio.2192] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2016] [Accepted: 08/01/2016] [Indexed: 12/22/2022]
Abstract
The integration of the water-oxidation enzyme, photosystem II (PSII), into electrodes allows the electrons extracted from water-oxidation to be harnessed for enzyme characterization and driving novel endergonic reactions. However, PSII continues to underperform in integrated photoelectrochemical systems despite extensive optimization efforts. Here, we performed protein-film photoelectrochemistry on spinach and Thermosynechococcus elongatus PSII, and identified a competing charge transfer pathway at the enzyme-electrode interface that short-circuits the known water-oxidation pathway: photo-induced O2 reduction occurring at the chlorophyll pigments. This undesirable pathway is promoted by the embedment of PSII in an electron-conducting matrix, a common strategy of enzyme immobilization. Anaerobicity helps to recover the PSII photoresponses, and unmasked the onset potentials relating to the QA/QB charge transfer process. These findings have imparted a fuller understanding of the charge transfer pathways within PSII and at photosystem-electrode interfaces, which will lead to more rational design of pigment-containing photoelectrodes in general.
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Affiliation(s)
- Jenny Z Zhang
- Department of Chemistry, University of Cambridge, Cambridge, UK
| | | | - Nicholas Paul
- Department of Chemistry, University of Cambridge, Cambridge, UK
| | - Elisabet Romero
- Department of Physics and Astronomy, VU Amsterdam, Amsterdam, The Netherlands
| | - Rienk van Grondelle
- Department of Physics and Astronomy, VU Amsterdam, Amsterdam, The Netherlands
| | - Erwin Reisner
- Department of Chemistry, University of Cambridge, Cambridge, UK
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14
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Zhang KM, Shen Y, Zhou XQ, Fang YM, Liu Y, Ma LQ. Photosynthetic electron-transfer reactions in the gametophyte of Pteris multifida reveal the presence of allelopathic interference from the invasive plant species Bidens pilosa. JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY B-BIOLOGY 2016; 158:81-8. [DOI: 10.1016/j.jphotobiol.2016.02.026] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/15/2015] [Revised: 01/24/2016] [Accepted: 02/15/2016] [Indexed: 10/22/2022]
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15
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Zabelin AA, Neverov KV, Krasnovsky AA, Shkuropatova VA, Shuvalov VA, Shkuropatov AY. Characterization of the low-temperature triplet state of chlorophyll in photosystem II core complexes: Application of phosphorescence measurements and Fourier transform infrared spectroscopy. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2016; 1857:782-8. [PMID: 27040752 DOI: 10.1016/j.bbabio.2016.03.029] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/04/2016] [Revised: 03/23/2016] [Accepted: 03/28/2016] [Indexed: 10/21/2022]
Abstract
Phosphorescence measurements at 77 K and light-induced FTIR difference spectroscopy at 95 K were applied to study of the triplet state of chlorophyll a ((3)Chl) in photosystem II (PSII) core complexes isolated from spinach. Using both methods, (3)Chl was observed in the core preparations with doubly reduced primary quinone acceptor QA. The spectral parameters of Chl phosphorescence resemble those in the isolated PSII reaction centers (RCs). The main spectral maximum and the lifetime of the phosphorescence corresponded to 955±1 nm and of 1.65±0.05 ms respectively; in the excitation spectrum, the absorption maxima of all core complex pigments (Chl, pheophytin a (Pheo), and β-carotene) were observed. The differential signal at 1667(-)/1628(+)cm(-1) reflecting a downshift of the stretching frequency of the 13(1)-keto C=O group of Chl was found to dominate in the triplet-minus-singlet FTIR difference spectrum of core complexes. Based on FTIR results and literature data, it is proposed that (3)Chl is mostly localized on the accessory chlorophyll that is in triplet equilibrium with P680. Analysis of the data suggests that the Chl triplet state responsible for the phosphorescence and the FTIR difference spectrum is mainly generated due to charge recombination in the reaction center radical pair P680(+)PheoD1(-), and the energy and temporal parameters of this triplet state as well as the molecular environment and interactions of the triplet-bearing Chl molecule are similar in the PSII core complexes and isolated PSII RCs.
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Affiliation(s)
- Alexey A Zabelin
- Institute of Basic Biological Problems, Russian Academy of Sciences, Pushchino, Moscow Region 142290, Russian Federation
| | - Konstantin V Neverov
- A.N. Bach Institute of Biochemistry, Russian Academy of Sciences, Leninskii pr., 33, Moscow 119071, Russian Federation; Biology Department, M.V. Lomonosov Moscow State University, Vorobyovy Gory, Moscow 119992, Russian Federation
| | - Alexander A Krasnovsky
- A.N. Bach Institute of Biochemistry, Russian Academy of Sciences, Leninskii pr., 33, Moscow 119071, Russian Federation; Biology Department, M.V. Lomonosov Moscow State University, Vorobyovy Gory, Moscow 119992, Russian Federation
| | - Valentina A Shkuropatova
- Institute of Basic Biological Problems, Russian Academy of Sciences, Pushchino, Moscow Region 142290, Russian Federation
| | - Vladimir A Shuvalov
- Institute of Basic Biological Problems, Russian Academy of Sciences, Pushchino, Moscow Region 142290, Russian Federation
| | - Anatoly Ya Shkuropatov
- Institute of Basic Biological Problems, Russian Academy of Sciences, Pushchino, Moscow Region 142290, Russian Federation.
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16
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Zabelin AA, Shkuropatova VA, Shkuropatov AY, Shuvalov VA. Temperature dependence of light-induced absorbance changes associated with chlorophyll photooxidation in manganese-depleted core complexes of photosystem II. BIOCHEMISTRY (MOSCOW) 2015; 80:1279-87. [DOI: 10.1134/s0006297915100089] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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17
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Neverov KV, Krasnovsky AA, Zabelin AA, Shuvalov VA, Shkuropatov AY. Low-temperature (77 K) phosphorescence of triplet chlorophyll in isolated reaction centers of photosystem II. PHOTOSYNTHESIS RESEARCH 2015; 125:43-49. [PMID: 25712165 DOI: 10.1007/s11120-015-0105-1] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/27/2014] [Accepted: 02/19/2015] [Indexed: 06/04/2023]
Abstract
Phosphorescence characterized by the main emission band at 952 ± 1 nm (1.30 eV), the lifetime of 1.5 ± 0.1 ms and the quantum yield nearly equal to that for monomeric chlorophyll a in aqueous detergent dispersions, has been detected in isolated reaction centers (RCs) of spinach photosystem II at 77 K. The excitation spectrum shows maxima corresponding to absorption bands of chlorophyll a, pheophytin a, and β-carotene. The phosphorescence intensity strongly depends upon the redox state of RCs. The data suggest that the phosphorescence signal originates from the chlorophyll triplet state populated via charge recombination in the radical pair [Formula: see text].
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Affiliation(s)
- Konstantin V Neverov
- A.N. Bach Institute of Biochemistry, Russian Academy of Sciences, Leninskii pr., 33, Moscow, 119071, Russian Federation
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18
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D'Haene SE, Sobotka R, Bučinská L, Dekker JP, Komenda J. Interaction of the PsbH subunit with a chlorophyll bound to histidine 114 of CP47 is responsible for the red 77K fluorescence of Photosystem II. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2015; 1847:1327-34. [PMID: 26164101 DOI: 10.1016/j.bbabio.2015.07.003] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/08/2015] [Revised: 07/03/2015] [Accepted: 07/07/2015] [Indexed: 10/23/2022]
Abstract
A characteristic feature of the active Photosystem II (PSII) complex is a red-shifted low temperature fluorescence emission at about 693nm. The origin of this emission has been attributed to a monomeric 'red' chlorophyll molecule located in the CP47 subunit. However, the identity and function of this chlorophyll remain uncertain. In our previous work, we could not detect the red PSII emission in a mutant of the cyanobacterium Synechocystis sp. PCC 6803 lacking PsbH, a small transmembrane subunit bound to CP47. However, it has not been clear whether the PsbH is structurally essential for the red emission or the observed effect of mutation has been indirectly caused by compromised PSII stability and function. In the present work we performed a detailed spectroscopic characterization of PSII in cells of a mutant lacking PsbH and Photosystem I and we also characterized PSII core complexes isolated from this mutant. In addition, we purified and characterized the CP47 assembly modules containing and lacking PsbH. The results clearly confirm an essential role of PsbH in the origin of the PSII red emission and also demonstrate that PsbH stabilizes the binding of one β-carotene molecule in PSII. Crystal structures of the cyanobacterial PSII show that PsbH directly interacts with a single monomeric chlorophyll ligated by the histidine 114 residue of CP47 and we conclude that this peripheral chlorophyll hydrogen-bonded to PsbH is responsible for the red fluorescence state of CP47. Given the proximity of β-carotene this state could participate in the dissipation of excessive light energy.
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Affiliation(s)
- Sandrine E D'Haene
- Biophysics of Photosynthesis/Physics of Energy, Department of Physics and Astronomy, Faculty of Sciences, VU University Amsterdam, De Boelelaan 1081, Amsterdam 1081 HV, The Netherlands.
| | - Roman Sobotka
- Institute of Microbiology, Laboratory of Photosynthesis, Centre Algatech, Opatovický mlýn, 379 81 Třeboň, Czech Republic; Faculty of Science, University of South Bohemia, Branišovská 31, České Budějovice, Czech Republic
| | - Lenka Bučinská
- Institute of Microbiology, Laboratory of Photosynthesis, Centre Algatech, Opatovický mlýn, 379 81 Třeboň, Czech Republic; Faculty of Science, University of South Bohemia, Branišovská 31, České Budějovice, Czech Republic
| | - Jan P Dekker
- Biophysics of Photosynthesis/Physics of Energy, Department of Physics and Astronomy, Faculty of Sciences, VU University Amsterdam, De Boelelaan 1081, Amsterdam 1081 HV, The Netherlands
| | - Josef Komenda
- Institute of Microbiology, Laboratory of Photosynthesis, Centre Algatech, Opatovický mlýn, 379 81 Třeboň, Czech Republic; Faculty of Science, University of South Bohemia, Branišovská 31, České Budějovice, Czech Republic
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19
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van Oort B, van Grondelle R, van Stokkum IHM. A Hidden State in Light-Harvesting Complex II Revealed By Multipulse Spectroscopy. J Phys Chem B 2015; 119:5184-93. [PMID: 25815531 PMCID: PMC4500649 DOI: 10.1021/acs.jpcb.5b01335] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2015] [Revised: 03/23/2015] [Indexed: 11/28/2022]
Abstract
Light-harvesting complex II (LHCII) is pivotal both for collecting solar radiation for photosynthesis, and for protection against photodamage under high light intensities (via a process called nonphotochemical quenching, NPQ). Aggregation of LHCII is associated with fluorescence quenching, and is used as an in vitro model system of NPQ. However, there is no agreement on the nature of the quencher and on the validity of aggregation as a model system. Here, we use ultrafast multipulse spectroscopy to populate a quenched state in unquenched (unaggregated) LHCII. The state shows characteristic features of lutein and chlorophyll, suggesting that it is an excitonically coupled state between these two compounds. This state decays in approximately 10 ps, making it a strong competitor for photodamage and photochemical quenching. It is observed in trimeric and monomeric LHCII, upon re-excitation with pulses of different wavelengths and duration. We propose that this state is always present, but is scarcely populated under low light intensities. Under high light intensities it may become more accessible, e.g. by conformational changes, and then form a quenching channel. The same state may be the cause of fluorescence blinking observed in single-molecule spectroscopy of LHCII trimers, where a small subpopulation is in an energetically higher state where the pathway to the quencher opens up.
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Affiliation(s)
- Bart van Oort
- Department
of Physics and Astronomy, Faculty of Sciences, VU University Amsterdam, De Boelelaan 1081, 1081 HV Amsterdam, The Netherlands
- Institute
for Lasers, Life and Biophotonics, Faculty of Sciences, VU University Amsterdam, De Boelelaan 1081, 1081 HV Amsterdam, The Netherlands
| | - Rienk van Grondelle
- Department
of Physics and Astronomy, Faculty of Sciences, VU University Amsterdam, De Boelelaan 1081, 1081 HV Amsterdam, The Netherlands
- Institute
for Lasers, Life and Biophotonics, Faculty of Sciences, VU University Amsterdam, De Boelelaan 1081, 1081 HV Amsterdam, The Netherlands
| | - Ivo H. M. van Stokkum
- Department
of Physics and Astronomy, Faculty of Sciences, VU University Amsterdam, De Boelelaan 1081, 1081 HV Amsterdam, The Netherlands
- Institute
for Lasers, Life and Biophotonics, Faculty of Sciences, VU University Amsterdam, De Boelelaan 1081, 1081 HV Amsterdam, The Netherlands
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20
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Zabelin AA, Shkuropatova VA, Makhneva ZK, Moskalenko AA, Shuvalov VA, Shkuropatov AY. Chemically modified reaction centers of photosystem II: Exchange of pheophytin a with 7-deformyl-7-hydroxymethyl-pheophytin b. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2014; 1837:1870-1881. [DOI: 10.1016/j.bbabio.2014.08.004] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/18/2014] [Revised: 08/14/2014] [Accepted: 08/19/2014] [Indexed: 11/28/2022]
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21
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Nadtochenko VA, Semenov AY, Shuvalov VA. Formation and decay of P680 (P(D1)-P(D2))⁺PheoD1⁻ radical ion pair in photosystem II core complexes. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2014; 1837:1384-8. [PMID: 24513193 DOI: 10.1016/j.bbabio.2014.01.026] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/02/2013] [Revised: 01/10/2014] [Accepted: 01/31/2014] [Indexed: 11/18/2022]
Abstract
Under physiological conditions (278 K) femtosecond pump-probe laser spectroscopy with 20-fs time resolution was applied to study primary charge separation in spinach photosystem II (PSII) core complexes excited at 710 nm. It was shown that initial formation of anion radical band of pheophytin molecule (Pheo⁻) at 460 nm is observed with rise time of ~11ps. The kinetics of the observed rise was ascribed to charge separation between Chl (chlorophyll a) dimer, primary electron donor in PSII (P680*) and Pheo located in D1 protein subunit (PheoD1) absorbing at 420 nm, 545 nm and 680 nm with formation of the ion-radical pair P680⁺PheoDI⁻. The subsequent electron transfer from Pheo(D1)⁻ to primary plastoquinone electron acceptor (Q(A)) was accompanied by relaxation of the 460-nm band and occurred within ~250 ps in good agreement with previous measurements in Photosystem II-enriched particles and bacterial reaction centers. The subtraction of the P680⁺ spectrum measured at 455 ps delay from the spectra at 23 ps or 44 ps delay reveals the spectrum of Pheo(DI)⁻, which is very similar to that measured earlier by accumulation method. The spectrum of Pheo(DI)⁻ formation includes a bleaching (or red shift) of the 670 nm band indicating that Chl-670 is close to Pheo(D1). According to previous measurements in the femtosecond-picosecond time range this Chl-670 was ascribed to Chl(D1) [Shelaev, Gostev, Vishnev, Shkuropatov, Ptushenko, Mamedov, Sarkisov, Nadtochenko, Semenov and Shuvalov, J. Photochemistry and Photobiology, B: Biology 104 (2011) 45-50]. Stimulated emission at 685 nm was found to have two decaying components with time constants of ~1ps and ~14ps. These components appear to reflect formation of P680⁺Chl(D1)⁻ and P680⁺Pheo(D1)⁻, respectively, as found earlier. This article is part of a special issue entitled: photosynthesis research for sustainability: keys to produce clean energy.
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Affiliation(s)
- V A Nadtochenko
- NN Semenov Institute of Chemical Physics, Russian Academy of Sciences, 119991 Moscow, Russia
| | - A Yu Semenov
- NN Semenov Institute of Chemical Physics, Russian Academy of Sciences, 119991 Moscow, Russia; A.N. Belozersky Institute of Physical-Chemical Biology, Moscow State University, 119991 Moscow, Russia
| | - V A Shuvalov
- A.N. Belozersky Institute of Physical-Chemical Biology, Moscow State University, 119991 Moscow, Russia; Institute of Basic Biological Problems, Russian Academy of Sciences, 142290 Pushchino, Moscow Region, Russia.
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22
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Pradhan S, Patra P, Das S, Chandra S, Mitra S, Dey KK, Akbar S, Palit P, Goswami A. Photochemical modulation of biosafe manganese nanoparticles on Vigna radiata: a detailed molecular, biochemical, and biophysical study. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2013; 47:13122-31. [PMID: 24144189 DOI: 10.1021/es402659t] [Citation(s) in RCA: 108] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/12/2023]
Abstract
Manganese (Mn) is an essential element for plants which intervenes mainly in photosynthesis. In this study we establish that manganese nanoparticles (MnNP) work as a better micronutrient than commercially available manganese salt, MnSO4 (MS) at recommended doses on leguminous plant mung bean (Vigna radiata) under laboratory condition. At higher doses it does not impart toxicity to the plant unlike MS. MnNP-treated chloroplasts show greater photophosphorylation, oxygen evolution with respect to control and MS-treated chloroplasts as determined by biophysical and biochemical techniques. Water splitting by an oxygen evolving complex is enhanced by MnNP in isolated chloroplast as confirmed by polarographic and spectroscopic techniques. Enhanced activity of the CP43 protein of a photosystem II (PS II) Mn4Ca complex influenced better phosphorylation in the electron transport chain in the case of MnNP-treated chloroplast, which is evaluated by sodium dodecyl sulfate polyacrylamide gel electrophoresis and corresponding Western blot analysis. To the best of our knowledge this is the first report to augment photosynthesis using MnNP and its detailed correlation with different molecular, biochemical and biophysical parameters of photosynthetic pathways. At effective dosage, MnNP is found to be biosafe both in plant and animal model systems. Therefore MnNP would be a novel potential nanomodulator of photochemistry in the agricultural sector.
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Affiliation(s)
- Saheli Pradhan
- Biological Sciences Division, Indian Statistical Institute , 203 B.T. Road, Kolkata 700108, India
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23
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Vishnev MI, Zabelin AA, Shkuropatova VA, Yanyushin MF, Shuvalov VA, Shkuropatov AY. Chemical modification of photosystem II core complex pigments with sodium borohydride. BIOCHEMISTRY (MOSCOW) 2013; 78:377-84. [DOI: 10.1134/s0006297913040068] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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24
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Fuller FD, Ogilvie JP. Continuum probe two-dimensional electronic spectroscopy of the photosystem II reaction center. EPJ WEB OF CONFERENCES 2013. [DOI: 10.1051/epjconf/20134108018] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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25
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Lewis KLM, Fuller FD, Myers JA, Yocum CF, Mukamel S, Abramavicius D, Ogilvie JP. Simulations of the two-dimensional electronic spectroscopy of the photosystem II reaction center. J Phys Chem A 2012; 117:34-41. [PMID: 23210463 DOI: 10.1021/jp3081707] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
We report simulations of the two-dimensional electronic spectroscopy of the Q(y) band of the D1-D2-Cyt b559 photosystem II reaction center at 77 K. We base the simulations on an existing Hamiltonian that was derived by simultaneous fitting to a wide range of linear spectroscopic measurements and described within modified Redfield theory. The model obtains reasonable agreement with most aspects of the two-dimensional spectra, including the overall peak shapes and excited state absorption features. It does not reproduce the rapid equilibration from high energy to low energy excitonic states evident by a strong cross-peak below the diagonal. We explore modifications to the model to incorporate new structural data and improve agreement with the two-dimensional spectra. We find that strengthening the system-bath coupling and lowering the degree of disorder significantly improves agreement with the cross-peak feature, while lessening agreement with the relative diagonal/antidiagonal width of the 2D spectra. We conclude that two-dimensional electronic spectroscopy provides a sensitive test of excitonic models of the photosystem II reaction center and discuss avenues for further refinement of such models.
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Affiliation(s)
- K L M Lewis
- Department of Physics and Biophysics, University of Michigan, Ann Arbor, Michigan 48109-1040, USA
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26
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Barera S, Pagliano C, Pape T, Saracco G, Barber J. Characterization of PSII-LHCII supercomplexes isolated from pea thylakoid membrane by one-step treatment with α- and β-dodecyl-D-maltoside. Philos Trans R Soc Lond B Biol Sci 2012; 367:3389-99. [PMID: 23148265 PMCID: PMC3497064 DOI: 10.1098/rstb.2012.0056] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
It was the work of Jan Anderson, together with Keith Boardman, that showed it was possible to physically separate photosystem I (PSI) from photosystem II (PSII), and it was Jan Anderson who realized the importance of this work in terms of the fluid-mosaic model as applied to the thylakoid membrane. Since then, there has been a steady progress in the development of biochemical procedures to isolate PSII and PSI both for physical and structural studies. Dodecylmaltoside (DM) has emerged as an effective mild detergent for this purpose. DM is a glucoside-based surfactant with a bulky hydrophilic head group composed of two sugar rings and a non-charged alkyl glycoside chain. Two isomers of this molecule exist, differing only in the configuration of the alkyl chain around the anomeric centre of the carbohydrate head group, axial in α-DM and equatorial in β-DM. We have compared the use of α-DM and β-DM for the isolation of supramolecular complexes of PSII by a single-step solubilization of stacked thylakoid membranes isolated from peas. As a result, we have optimized conditions to obtain homogeneous preparations of the C(2)S(2)M(2) and C(2)S(2) supercomplexes following the nomenclature of Dekker & Boekema (2005 Biochim. Biophys. Acta 1706, 12-39). These PSII-LHCII supercomplexes were subjected to biochemical and structural analyses.
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Affiliation(s)
- Simone Barera
- Applied Science and Technology Department—BioSolar Laboratory, Politecnico di Torino, Viale T. Michel 5, 15121 Alessandria, Italy
- Science and Technological Innovation Department, University of Piemonte Orientale ‘Amedeo Avogadro’, Viale T. Michel 11, 15121 Alessandria, Italy
| | - Cristina Pagliano
- Applied Science and Technology Department—BioSolar Laboratory, Politecnico di Torino, Viale T. Michel 5, 15121 Alessandria, Italy
| | - Tillmann Pape
- Division of Molecular Biosciences, Department of Life Sciences, Imperial College London, London SW7 2AZ, UK
| | - Guido Saracco
- Applied Science and Technology Department—BioSolar Laboratory, Politecnico di Torino, Viale T. Michel 5, 15121 Alessandria, Italy
| | - James Barber
- Applied Science and Technology Department—BioSolar Laboratory, Politecnico di Torino, Viale T. Michel 5, 15121 Alessandria, Italy
- Division of Molecular Biosciences, Department of Life Sciences, Imperial College London, London SW7 2AZ, UK
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Wahadoszamen M, Berera R, Ara AM, Romero E, van Grondelle R. Identification of two emitting sites in the dissipative state of the major light harvesting antenna. Phys Chem Chem Phys 2011; 14:759-66. [PMID: 22120671 DOI: 10.1039/c1cp23059j] [Citation(s) in RCA: 75] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
In order to cope with the deleterious effects of excess light, photosynthetic organisms have developed remarkable strategies where the excess energy is dissipated as heat by the antenna system. In higher plants one main player in the process is the major light harvesting antenna of Photosystem II (PSII), LHCII. In this paper we applied Stark fluorescence spectroscopy to LHCII in different quenching states to investigate the possible contribution of charge-transfer states to the quenching. We find that in the quenched state the fluorescence displays a remarkable sensitivity to the applied electric field. The resulting field-induced emission spectra reveal the presence of two distinct energy dissipating sites both characterized by a strong but spectrally very different response to the applied electric field. We propose the two states to originate from chlorophyll-chlorophyll and chlorophyll-carotenoid charge transfer interactions coupled to the chlorophyll exciton state in the terminal emitter locus and discuss these findings in the light of the different models proposed to be responsible for energy dissipation in photosynthesis.
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Affiliation(s)
- Md Wahadoszamen
- Division of Physics and Astronomy, Department of Biophysics, VU University Amsterdam, Amsterdam, The Netherlands.
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28
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Bhalla V, Zazubovich V. Self-assembly and sensor response of photosynthetic reaction centers on screen-printed electrodes. Anal Chim Acta 2011; 707:184-90. [PMID: 22027137 DOI: 10.1016/j.aca.2011.09.020] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2011] [Revised: 09/08/2011] [Accepted: 09/15/2011] [Indexed: 11/24/2022]
Abstract
Photosynthetic reaction centers were immobilized onto gold screen-printed electrodes (Au-SPEs) using a self-assembled monolayer (SAM) of mercaptopropionic acid (MPA) which was deliberately defective in order to achieve effective mediator transfer to the electrodes. The pure Photosystem II (PS II) cores from spinach immobilize onto the electrodes very efficiently but fair badly in terms of photocurrent response (measured using duroquinone as the redox mediator). The cruder preparation of PS II known as BBY particles performs significantly better under the same experimental conditions and shows a photocurrent response of 20-35 nA (depending on preparation) per screen-printed electrode surface (12.5mm(2)). The data was corroborated using AFM, showing that in the case of BBY particles a defective biolayer is indeed formed, with grooves spanning the whole thickness of the layer enhancing the possibility of mass transfer to the electrodes and enabling biosensing. In comparison, the PS II core layer showed ultra-dense organization, with additional formation of aggregates on top of the single protein layer, thus blocking mediator access to the electrodes and/or binding sites. The defective monolayer biosensor with BBY particles was successfully applied for the detection of photosynthesis inhibitors, demonstrating that the inhibitor binding site remained accessible to both the inhibitor and the external redox mediator. Biosensing was demonstrated using picric acid and atrazine. The detection limits were 1.15 nM for atrazine and 157 nM for picric acid.
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Affiliation(s)
- Vijayender Bhalla
- Department of Physics, Concordia University, Montreal, Quebec, Canada.
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29
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Klenina IB, Kuzmin AN, Fufina TY, Gudkov ND, Proskuryakov II. Triplet state of the primary donor in reaction centers of the phototrophic bacterium Rhodobacter sphaeroides R26 with active photoinduced electron transfer. Biophysics (Nagoya-shi) 2011. [DOI: 10.1134/s0006350911030110] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
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30
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P680 (PD1PD2) and ChlD1 as alternative electron donors in photosystem II core complexes and isolated reaction centers. JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY B-BIOLOGY 2011; 104:44-50. [DOI: 10.1016/j.jphotobiol.2011.02.003] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/20/2010] [Revised: 01/25/2011] [Accepted: 02/03/2011] [Indexed: 12/13/2022]
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31
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32
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Pagliano C, Chimirri F, Saracco G, Marsano F, Barber J. One-step isolation and biochemical characterization of a highly active plant PSII monomeric core. PHOTOSYNTHESIS RESEARCH 2011; 108:33-46. [PMID: 21487931 DOI: 10.1007/s11120-011-9650-4] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/18/2011] [Accepted: 03/28/2011] [Indexed: 05/03/2023]
Abstract
We describe a one-step detergent solubilization protocol for isolating a highly active form of Photosystem II (PSII) from Pisum sativum L. Detailed characterization of the preparation showed that the complex was a monomer having no light harvesting proteins attached. This core reaction centre complex had, however, a range of low molecular mass intrinsic proteins as well as the chlorophyll binding proteins CP43 and CP47 and the reaction centre proteins D1 and D2. Of particular note was the presence of a stoichiometric level of PsbW, a low molecular weight protein not present in PSII of cyanobacteria. Despite the high oxygen evolution rate, the core complex did not retain the PsbQ extrinsic protein although there was close to a full complement of PsbO and PsbR and partial level of PsbP. However, reconstitution of PsbP and PsbPQ was possible. The presence of PsbP in absence of LHCII and other chlorophyll a/b binding proteins confirms that LHCII proteins are not a strict requirement for the assembly of this extrinsic polypeptide to the PSII core in contrast with the conclusion of Caffarri et al. (2009).
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Affiliation(s)
- Cristina Pagliano
- Department of Materials Science and Chemical Engineering - BioSolar Lab, Politecnico di Torino, Viale T. Michel 5, 15121, Alessandria, Italy.
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33
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Krüger TPJ, Novoderezhkin VI, Ilioaia C, van Grondelle R. Fluorescence spectral dynamics of single LHCII trimers. Biophys J 2010; 98:3093-101. [PMID: 20550923 DOI: 10.1016/j.bpj.2010.03.028] [Citation(s) in RCA: 119] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2009] [Revised: 02/26/2010] [Accepted: 03/15/2010] [Indexed: 10/19/2022] Open
Abstract
Single-molecule spectroscopy was employed to elucidate the fluorescence spectral heterogeneity and dynamics of individual, immobilized trimeric complexes of the main light-harvesting complex of plants in solution near room temperature. Rapid reversible spectral shifts between various emitting states, each of which was quasi-stable for seconds to tens of seconds, were observed for a fraction of the complexes. Most deviating states were characterized by the appearance of an additional, red-shifted emission band. Reversible shifts of up to 75 nm were detected. By combining modified Redfield theory with a disordered exciton model, fluorescence spectra with peaks between 670 nm and 705 nm could be explained by changes in the realization of the static disorder of the pigment-site energies. Spectral bands beyond this wavelength window suggest the presence of special protein conformations. We attribute the large red shifts to the mixing of an excitonic state with a charge-transfer state in two or more strongly coupled chlorophylls. Spectral bluing is explained by the formation of an energy trap before excitation energy equilibration is completed.
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Affiliation(s)
- Tjaart P J Krüger
- Department of Biophysics, Faculty of Sciences, Vrije Universiteit, Amsterdam, The Netherlands.
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34
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Kamlowski A, Frankemöller L, van der Est A, Stehlik D, Holzwart AR. Evidence for delocalization of the triplet state 3P680 in the D1D2cytb559-complex of photosystem II. ACTA ACUST UNITED AC 2010. [DOI: 10.1002/bbpc.19961001221] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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35
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Stahl AD, Di Donato M, van Stokkum I, van Grondelle R, Groot ML. A femtosecond visible/visible and visible/mid-infrared transient absorption study of the light harvesting complex II. Biophys J 2010; 97:3215-23. [PMID: 20006959 DOI: 10.1016/j.bpj.2009.09.037] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2009] [Revised: 08/11/2009] [Accepted: 09/15/2009] [Indexed: 01/11/2023] Open
Abstract
Light harvesting complex II (LHCII) is the most abundant protein in the thylakoid membrane of higher plants and green algae. LHCII acts to collect solar radiation, transferring this energy mainly toward photosystem II, with a smaller amount going to photosystem I; it is then converted into a chemical, storable form. We performed time-resolved femtosecond visible pump/mid-infrared probe and visible pump/visible probe absorption difference spectroscopy on purified LHCII to gain insight into the energy transfer in this complex occurring in the femto-picosecond time regime. We find that information derived from mid-infrared spectra, together with structural and modeling information, provides a unique visualization of the flow of energy via the bottleneck pigment chlorophyll a604.
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Affiliation(s)
- Andreas D Stahl
- Faculty of Sciences, Department of Physics and Astronomy, VU University Amsterdam, Amsterdam, The Netherlands
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36
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Ren Y, Zhang C, Bao H, Shen J, Zhao J. Probing tyrosine Z oxidation in Photosystem II core complex isolated from spinach by EPR at liquid helium temperatures. PHOTOSYNTHESIS RESEARCH 2009; 99:127-138. [PMID: 19214772 DOI: 10.1007/s11120-009-9410-x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/07/2008] [Accepted: 01/23/2009] [Indexed: 05/27/2023]
Abstract
Tyrosine Z (Tyr(Z)) oxidation observed at liquid helium temperatures provides new insights into the structure and function of Tyr(Z) in active Photosystem II (PSII). However, it has not been reported in PSII core complex from higher plants. Here, we report Tyr(Z) oxidation in the S(1) and S(2) states in PSII core complex from spinach for the first time. Moreover, we identified a 500 G-wide symmetric EPR signal (peak position g = 2.18, trough position g = 1.85) together with the g = 2.03 signal induced by visible light at 10 K in the S(1) state in the PSII core complex. These two signals decay with a similar rate in the dark and both disappear in the presence of 6% methanol. We tentatively assign this new feature to the hyperfine structure of the S(1)Tyr(Z)(*) EPR signal. Furthermore, EPR signals of the S(2) state of the Mn-cluster, the oxidation of the non-heme iron, and the S(1)Tyr(Z)(*) in PSII core complexes and PSII-enriched membranes from spinach are compared, which clearly indicate that both the donor and acceptor sides of the reaction center are undisturbed after the removal of LHCII. These results suggest that the new spinach PSII core complex is suitable for the electron transfer study of PSII at cryogenic temperatures.
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Affiliation(s)
- Yanan Ren
- Laboratory of Photochemistry, Beijing National Laboratory of Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, Beijing, China
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37
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Fey H, Piano D, Horn R, Fischer D, Schmidt M, Ruf S, Schröder WP, Bock R, Büchel C. Isolation of highly active photosystem II core complexes with a His-tagged Cyt b559 subunit from transplastomic tobacco plants. BIOCHIMICA ET BIOPHYSICA ACTA 2008; 1777:1501-9. [PMID: 18973745 DOI: 10.1016/j.bbabio.2008.09.012] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/06/2008] [Revised: 09/25/2008] [Accepted: 09/26/2008] [Indexed: 10/21/2022]
Abstract
Photosystem II (PSII) is a huge multi-protein-complex consisting, in higher plants and green algae, of the PS II core and the adjacent light harvesting proteins. In the study reported here, N-terminal His-tags were added to the plastome-encoded alpha-subunit of cytochrome b559, PsbE, in tobacco plants, thus facilitating rapid, mild purification of higher plant PSII. Biolistic chloroplast transformation was used to replace the wildtype psbE gene by His-tagged counterparts. Transgenic plants did not exhibit an obvious phenotype. However, the oxygen evolution capacity of thylakoids prepared from the mutants compared to the wildtype was reduced by 10-30% depending on the length of the His-tag, although Fv/Fm values differed only slightly. Homoplasmic F1 plants were used to isolate PSII cores complexes. The cores contained no detectable traces of LHC or PsaA/B polypeptides, but the main core subunits of PSII could be identified using immunodetection and mass spectroscopy. In addition, Psb27 and PsbS were detected. The presence of the former was presumably due to the preparation method, since PSII complexes located in the stroma are also isolated. In contrast to previous reports, PsbS was solely found as a monomer on SDS-PAGE in the PSII core complexes of tobacco.
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Affiliation(s)
- Holger Fey
- Institute of Molecular Biosciences, University of Frankfurt, Siesmayerstr. 70, D60323 Frankfurt, Germany
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38
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Shelaev IV, Gostev FE, Nadtochenko VA, Shkuropatov AY, Zabelin AA, Mamedov MD, Semenov AY, Sarkisov OM, Shuvalov VA. Primary light-energy conversion in tetrameric chlorophyll structure of photosystem II and bacterial reaction centers: II. Femto- and picosecond charge separation in PSII D1/D2/Cyt b559 complex. PHOTOSYNTHESIS RESEARCH 2008; 98:95-103. [PMID: 18855113 DOI: 10.1007/s11120-008-9371-5] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/04/2008] [Accepted: 09/15/2008] [Indexed: 05/26/2023]
Abstract
In Part I of the article, a review of recent data on electron-transfer reactions in photosystem II (PSII) and bacterial reaction center (RC) has been presented. In Part II, transient absorption difference spectroscopy with 20-fs resolution was applied to study the primary charge separation in PSII RC (DI/DII/Cyt b 559 complex) excited at 700 nm at 278 K. It was shown that the initial electron-transfer reaction occurs within 0.9 ps with the formation of the charge-separated state P680(+)Chl(D1)(-), which relaxed within 14 ps as indicated by reversible bleaching of 670-nm band that was tentatively assigned to the Chl(D1) absorption. The subsequent electron transfer from Chl(D1)(-) within 14 ps was accompanied by a development of the radical anion band of Pheo(D1) at 445 nm, attributable to the formation of the secondary radical pair P680(+)Pheo(D1)(-). The key point of this model is that the most blue Q(y) transition of Chl(D1) in RC is allowing an effective stabilization of separated charges. Although an alternative mechanism of charge separation with Chl(D1)* as a primary electron donor and Pheo(D1) as a primary acceptor can not be ruled out, it is less consistent with the kinetics and spectra of absorbance changes induced in the PSII RC preparation by femtosecond excitation at 700 nm.
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Affiliation(s)
- I V Shelaev
- NN Semenov Institute of Chemical Physics, Russian Academy of Sciences, 117991 Moscow, Russia
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39
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Martínez-Junza V, Szczepaniak M, Braslavsky SE, Sander J, Nowaczyk M, Rögner M, Holzwarth AR. A photoprotection mechanism involving the D(2) branch in photosystem II cores with closed reaction centers. Photochem Photobiol Sci 2008; 7:1337-43. [PMID: 18958320 DOI: 10.1039/b809884k] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Nanosecond transient absorption spectroscopy has been used to study reaction centre (RC) chlorophyll triplet quenching by carotenoid in intact photosystem II cores from T. elongatus with closed RCs. We found a triplet beta-carotene ((3)Car) signal (absorption difference maximum at 530 nm) that is sensitized by the RC chlorophyll (Chl) triplet with a formation time of ca. 190 ns, has a decay time of 7 micros and is formed with a quantum yield between 10 and 20%. The (3)Car signal is assigned to the beta-carotene on the D(2) branch of the RC. We thus propose a new photoprotection mechanism operative in closed RCs where-as a consequence of the negative charge on the quinone Q(A)-the triplet chlorophyll ((3)Chl) is formed by the radical pair (RP) mechanism on the normally inactive D(2) branch where it can be subsequently quenched by the D(2) beta-carotene. We suggest that the D(2) branch becomes active when the RCs are closed under high light fluence conditions. Under these conditions the D(2) branch plays a photoprotective role. This interpretation allows combining many seemingly inconsistent observations in the literature and reveals the so far missing RC triplet quenching mechanism in photosystem II. The newly proposed mechanism also explains the reason why this RC triplet quenching is not observed in isolated D(1)-D(2)-cyt b(559) RCs. If Q(A) is either not present at all (as in the isolated RC) or is not charged (as in open RCs or with doubly reduced Q(A)) then the RC (3)Chl is formed on the D(1) branch. The D(1) branch (3)Chl can not be quenched due to the large distance to the beta-carotene. This interpretation is actually in line with the well-known (3)RC quenching mechanism in bacterial RCs, where also the carotenoid in the (analogous to the D(2) branch) B-branch of the RC becomes the quencher.
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40
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Clausen J, Junge W. The terminal reaction cascade of water oxidation: proton and oxygen release. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2008; 1777:1311-8. [PMID: 18640091 DOI: 10.1016/j.bbabio.2008.06.009] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/15/2008] [Revised: 06/09/2008] [Accepted: 06/12/2008] [Indexed: 10/21/2022]
Abstract
In cyanobacteria, algae and plants Photosystem II produces the oxygen we breathe. Driven and clocked by light quanta, the catalytic Mn(4)Ca-tyrosine centre accumulates four oxidising equivalents before it abstracts four electrons from water, liberating dioxygen and protons. Aiming at intermediates of the terminal four-electron cascade, we previously have suppressed this reaction by elevating the oxygen pressure, thereby stabilising one redox intermediate. Here, we established a similar suppression by increasing the proton concentration. Data were analysed in terms of only one (peroxy) redox intermediate between the fourfold oxidised Mn(4)Ca-tyrosine centre and oxygen release. The surprising result was that the release into the bulk of one proton per dioxygen is linked to the first and rate-limiting electron transfer in the cascade rather than to the second which produces free oxygen. The penultimate intermediate might thus be conceived as a fully deprotonated peroxy-moiety.
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Affiliation(s)
- Juergen Clausen
- Abteilung Biophysik, Fachbereich Biologie/Chemie, Universität Osnabrück, Osnabrück, Germany
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41
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42
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van der Weij-de Wit CD, Ihalainen JA, van Grondelle R, Dekker JP. Excitation energy transfer in native and unstacked thylakoid membranes studied by low temperature and ultrafast fluorescence spectroscopy. PHOTOSYNTHESIS RESEARCH 2007; 93:173-82. [PMID: 17390231 DOI: 10.1007/s11120-007-9157-1] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/22/2006] [Accepted: 03/02/2007] [Indexed: 05/14/2023]
Abstract
In this work, the transfer of excitation energy was studied in native and cation-depletion induced, unstacked thylakoid membranes of spinach by steady-state and time-resolved fluorescence spectroscopy. Fluorescence emission spectra at 5 K show an increase in photosystem I (PSI) emission upon unstacking, which suggests an increase of its antenna size. Fluorescence excitation measurements at 77 K indicate that the increase of PSI emission upon unstacking is caused both by a direct spillover from the photosystem II (PSII) core antenna and by a functional association of light-harvesting complex II (LHCII) to PSI, which is most likely caused by the formation of LHCII-LHCI-PSI supercomplexes. Time-resolved fluorescence measurements, both at room temperature and at 77 K, reveal differences in the fluorescence decay kinetics of stacked and unstacked membranes. Energy transfer between LHCII and PSI is observed to take place within 25 ps at room temperature and within 38 ps at 77 K, consistent with the formation of LHCII-LHCI-PSI supercomplexes. At the 150-160 ps timescale, both energy transfer from LHCII to PSI as well as spillover from the core antenna of PSII to PSI is shown to occur at 77 K. At room temperature the spillover and energy transfer to PSI is less clear at the 150 ps timescale, because these processes compete with charge separation in the PSII reaction center, which also takes place at a timescale of about 150 ps.
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Affiliation(s)
- C D van der Weij-de Wit
- Faculty of Sciences, Department of Physics and Astronomy, Section Biophysics, Vrije Universiteit, De Boelelaan 1081, Amsterdam, 1081 HV, The Netherlands.
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43
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McConnell IL, Badger MR, Wydrzynski T, Hillier W. A quantitative assessment of the carbonic anhydrase activity in photosystem II. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2007; 1767:639-47. [PMID: 17467655 DOI: 10.1016/j.bbabio.2007.01.019] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/13/2006] [Revised: 01/25/2007] [Accepted: 01/26/2007] [Indexed: 11/15/2022]
Abstract
Using a carbonic anhydrase assay based on membrane inlet mass spectrometry (MIMS), we have extended our earlier investigations of Photosystem II (PSII)-associated carbonic anhydrase activity in spinach PSII preparations (W. Hillier, I. McConnell, M. R. Badger, A. Boussac, V.V. Klimov G. C. Dismukes, T. Wydrzynski Biochemistry 2006, 45:2094). The relationship between the carbonic anhydrase activity and O(2) evolution has been evaluated in terms of the effects of metal ion addition, preparation type, light, and response to specific inhibitors. The results indicate that the PSII-associated carbonic anhydrase activity is variable and appears not to be associated specifically with the oxygen evolving activity nor the 33 kDa extrinsic manganese stabilising protein.
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Affiliation(s)
- I L McConnell
- Research School of Biological Sciences, The Australian National University, Canberra, ACT 0200, Australia.
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44
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Klenina IB, Feikema WO, Gast P, Zvereva MG, Proskuryakov II. Mechanism of photoinduced electron transfer in photosystem II reaction centers. Biophysics (Nagoya-shi) 2007. [DOI: 10.1134/s0006350907010083] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
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45
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Feikema WO, Gast P, Klenina IB, Proskuryakov II. EPR characterisation of the triplet state in photosystem II reaction centers with singly reduced primary acceptor Q(A). BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2005; 1709:105-12. [PMID: 16095558 DOI: 10.1016/j.bbabio.2005.07.004] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/10/2004] [Revised: 07/14/2005] [Accepted: 07/18/2005] [Indexed: 11/30/2022]
Abstract
The triplet states of photosystem II core particles from spinach were studied using time-resolved cw EPR technique at different reduction states of the iron--quinone complex of the reaction center primary electron acceptor. With doubly reduced primary acceptor, the well-known photosystem II triplet state characterised by zero-field splitting parameters |D|=0.0286 cm(-1), |E|=0.0044 cm(-1) was detected. When the primary acceptor was singly reduced either chemically or photochemically, a triplet state of a different spectral shape was observed, bearing the same D and E values and characteristic spin polarization pattern arising from RC radical pair recombination. The latter triplet state was strongly temperature dependent disappearing at T=100 K, and had a much faster decay than the former one. Based on its properties, this triplet state was also ascribed to the photosystem II reaction center. A sequence of electron-transfer events in the reaction centers is proposed that explains the dependence of the triplet state properties on the reduction state of the iron--quinone primary acceptor complex.
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Affiliation(s)
- W Onno Feikema
- Department of Biophysics, Huygens Laboratory, P.O. Box 9504, 2300 RA Leiden, The Netherlands
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46
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Kropacheva TN, Germano M, Zucchelli G, Jennings RC, van Gorkom HJ. Circular dichroism of the peripheral chlorophylls in photosystem II reaction centers revealed by electrochemical oxidation. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2005; 1709:119-26. [PMID: 16054591 DOI: 10.1016/j.bbabio.2005.04.005] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/07/2005] [Revised: 04/14/2005] [Accepted: 04/19/2005] [Indexed: 11/19/2022]
Abstract
Visible absorption spectra and circular dichroism (CD) of the red absorption band of isolated photosystem II reaction centers were measured at room temperature during progressive bleaching by electrochemical oxidation, in comparison with aerobic photochemical destruction, and with anaerobic photooxidation in the presence of the artificial electron acceptor silicomolybdate. Initially, selective bleaching of peripheral chlorophylls absorbing at 672 nm was obtained by electrochemical oxidation at +0.9 V, whereas little selectivity was observed at higher potentials. Illumination in the presence of silicomolybdate did not cause a bleaching but a spectral broadening of the 672-nm band was observed, apparently in response to the oxidation of carotene. The 672-nm absorption band is shown to exhibit a positive CD, which accounts for the 674-nm shoulder in CD spectra at low temperature. The origin of this CD is discussed in view of the observation that all CD disappears with the 680-nm absorption band during aerobic photodestruction.
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Affiliation(s)
- Tatyana N Kropacheva
- Chemistry Department, Udmurt State University, Universitetskaya 1, Izhevsk 426037, Russia.
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Andrizhiyevskaya EG, Chojnicka A, Bautista JA, Diner BA, van Grondelle R, Dekker JP. Origin of the F685 and F695 fluorescence in photosystem II. PHOTOSYNTHESIS RESEARCH 2005; 84:173-80. [PMID: 16049771 DOI: 10.1007/s11120-005-0478-7] [Citation(s) in RCA: 114] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/07/2004] [Accepted: 01/12/2005] [Indexed: 05/03/2023]
Abstract
The emission spectra of CP47-RC and core complexes of Photosystem II (PS II) were measured at different temperatures and excitation wavelengths in order to establish the origin of the emission and the role of the core antenna in the energy transfer and charge separation processes in PS II. Both types of particles reveal strong dependences of spectral shape and yield on temperature. The results indicate that the well-known F-695 emission at 77 K arises from excitations that are trapped on a red-absorbing CP47 chlorophyll, whereas the F-685 nm emission at 77 K arises from excitations that are transferred slowly from 683 nm states in CP47 and CP43 to the RC, where they are trapped by charge separation. We conclude that F-695 at 77 K originates from the low-energy part of the inhomogeneous distribution of the 690 nm absorbing chlorophyll of CP47, while at 4 K the fluorescence originates from the complete distribution of the 690 nm chlorophyll of CP47 and from the low-energy part of the inhomogeneous distribution of one or more CP43 chlorophylls.
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Affiliation(s)
- Elena G Andrizhiyevskaya
- Faculty of Sciences, Division of Physics and Astronomy, Vrije Universiteit, De Boelelaan 1081, 1081 HV, Amsterdam, The Netherlands.
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Germano M, Gradinaru CC, Shkuropatov AY, van Stokkum IHM, Shuvalov VA, Dekker JP, van Grondelle R, van Gorkom HJ. Energy and electron transfer in photosystem II reaction centers with modified pheophytin composition. Biophys J 2004; 86:1664-72. [PMID: 14990494 PMCID: PMC1304002 DOI: 10.1016/s0006-3495(04)74235-6] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
Abstract
Energy and electron transfer in Photosystem II reaction centers in which the photochemically inactive pheophytin had been replaced by 13(1)-deoxo-13(1)-hydroxy pheophytin were studied by femtosecond transient absorption-difference spectroscopy at 77 K and compared to the dynamics in untreated reaction center preparations. Spectral changes induced by 683-nm excitation were recorded both in the Q(Y) and in the Q(X) absorption regions. The data could be described by a biphasic charge separation. In untreated reaction centers the major component had a time constant of 3.1 ps and the minor component 33 ps. After exchange, time constants of 0.8 and 22 ps were observed. The acceleration of the fast phase is attributed in part to the redistribution of electronic transitions of the six central chlorin pigments induced by replacement of the inactive pheophytin. In the modified reaction centers, excitation of the lowest energy Q(Y) transition produces an excited state that appears to be localized mainly on the accessory chlorophyll in the active branch (B(A) in bacterial terms) and partially on the active pheophytin H(A). This state equilibrates in 0.8 ps with the radical pair. B(A) is proposed to act as the primary electron donor also in untreated reaction centers. The 22-ps (pheophytin-exchanged) or 33-ps (untreated) component may be due to equilibration with the secondary radical pair. Its acceleration by H(B) exchange is attributed to a faster reverse electron transfer from B(A) to. After exchange both and are nearly isoenergetic with the excited state.
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Affiliation(s)
- M Germano
- Biophysics Department, Huygens Laboratory, Leiden University, 2300 RA Leiden, Netherlands
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Clausen J, Debus RJ, Junge W. Time-resolved oxygen production by PSII: chasing chemical intermediates. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2004; 1655:184-94. [PMID: 15100031 DOI: 10.1016/j.bbabio.2003.06.001] [Citation(s) in RCA: 60] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/11/2003] [Revised: 06/25/2003] [Accepted: 06/25/2003] [Indexed: 11/21/2022]
Abstract
Photosystem II (PSII) produces dioxygen from water in a four-stepped process, which is driven by four quanta of light and catalysed by a Mn-cluster and tyrosine Z. Oxygen is liberated during one step, coined S(3)=>S(0). Chemical intermediates on the way from reversibly bound water to dioxygen have not yet been tracked, however, a break in the Arrhenius plot of the oxygen-evolving step has been taken as evidence for its existence. We scrutinised the temperature dependence of (i) UV-absorption transients attributable to the reduction of the Mn-cluster and tyrosine Z by water, and (ii) polarographic transients attributable to the release of dioxygen. Using a centrifugatable and kinetically competent Pt-electrode, we observed no deviation from a linear Arrhenius plot of oxygen release in the temperature range from -2 to 32 degrees C, and hence no evidence, by this approach, for a sufficiently long-lived chemical intermediate. The half-rise times of oxygen release differed between Synechocystis WT* (at 20 degrees C: 1.35 ms) and a point mutant (D1-D61N: 13.1 ms), and the activation energies differed between species (Spinacia oleracea, 30 kJ/mol versus Synechocystis, 41 kJ/mol) and preparations (PSII membranes, 41 kJ/mol versus core complexes, 33 kJ/mol, Synechocystis). Correction for polarographic artefacts revealed, for the first time, a temperature-dependent lag-phase of the polarographic transient (duration at 20 degrees C: 0.45 ms, activation energy: 31 kJ/mol), which was indicative of a short-lived intermediate. It was, however, not apparent in the UV-transients. Thus the "intermediate" was probably newly formed and transiently bound oxygen.
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Affiliation(s)
- Jürgen Clausen
- Abteilung Biophysik, Fachbereich Biologie/Chemie, Barbarastr. 11, Universität Osnabrück, D-49069 Osnabrück, Germany
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Andrizhiyevskaya EG, Frolov D, van Grondelle R, Dekker JP. On the role of the CP47 core antenna in the energy transfer and trapping dynamics of Photosystem II. Phys Chem Chem Phys 2004. [DOI: 10.1039/b411977k] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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