1
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Forde A, Maity S, Freixas VM, Fernandez-Alberti S, Neukirch AJ, Kleinekathöfer U, Tretiak S. Stabilization of Charge-Transfer Excited States in Biological Systems: A Computational Focus on the Special Pair in Photosystem II Reaction Centers. J Phys Chem Lett 2024; 15:4142-4150. [PMID: 38593451 DOI: 10.1021/acs.jpclett.4c00362] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/11/2024]
Abstract
Charge-transfer (CT) excited states play an important role in many biological processes. However, many computational approaches often inadequately address the equilibration effects of nuclear and environmental degrees of freedom on these states. One prominent example of systems in which CT states are of utmost importance is reaction centers (RC) in photosystems. Here we use a multiscale approach combined with time-dependent density functional theory to explore the lowest CT excited state of the special pair PD1-PD2 in the Photosystem II-RC of a cyanobacterium. We find that the nonequilibrium CT excited state resides near the Soret band, making an exciton the lowest-energy excited state. However, accounting for nuclear and state-specific dielectric equilibration along the CT potential energy surface (PES), the CT state PD1--PD2+ stabilizes energetically below the excitonic state. This underscores the crucial role of state-specific solvation in mapping the PES of CT states, as demonstrated in a simplified dimer model.
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Affiliation(s)
- Aaron Forde
- Theoretical Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, United States
- Center for Nonlinear Studies, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, United States
| | - Sayan Maity
- School of Science, Constructor University, Campus Ring 1, 28759 Bremen, Germany
| | - Victor M Freixas
- Departamento de Ciencia y Tecnologiia, Univresidad Nacional de Quilmes/CONICET, B1876BXD Bernal, Argentina
| | | | - Amanda J Neukirch
- Theoretical Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, United States
| | | | - Sergei Tretiak
- Theoretical Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, United States
- Center for Integrated Nanotechnologies, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, United States
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2
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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] [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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3
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Silori Y, Willow R, Nguyen HH, Shen G, Song Y, Gisriel CJ, Brudvig GW, Bryant DA, Ogilvie JP. Two-Dimensional Electronic Spectroscopy of the Far-Red-Light Photosystem II Reaction Center. J Phys Chem Lett 2023; 14:10300-10308. [PMID: 37943008 DOI: 10.1021/acs.jpclett.3c02604] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2023]
Abstract
Understanding the role of specific pigments in primary energy conversion in the photosystem II (PSII) reaction center has been impeded by the spectral overlap of its constituent pigments. When grown in far-red light, some cyanobacteria incorporate chlorophyll-f and chlorophyll-d into PSII, relieving the spectral congestion. We employ two-dimensional electronic spectroscopy to study PSII at 77 K from Synechococcus sp. PCC 7335 cells that were grown in far-red light (FRL-PSII). We observe the formation of a radical pair within ∼3 ps that we assign to ChlD1•-PD1•+. While PheoD1 is thought to act as the primary electron acceptor in PSII from cells grown in visible light, we see no evidence of its involvement, which we attribute to its reduction by dithionite treatment in our samples. Our work demonstrates that primary charge separation occurs between ChlD1 and PD1 in FRL-PSII, suggesting that PD1/PD2 may play an underappreciated role in PSII's charge separation mechanism.
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Affiliation(s)
- Yogita Silori
- Department of Physics and Biophysics, University of Michigan, 450 Church Street, Ann Arbor, Michigan 48109, United States
| | - Rhiannon Willow
- Department of Physics and Biophysics, University of Michigan, 450 Church Street, Ann Arbor, Michigan 48109, United States
| | - Hoang H Nguyen
- Department of Physics and Biophysics, University of Michigan, 450 Church Street, Ann Arbor, Michigan 48109, United States
| | - Gaozhong Shen
- Department of Biochemistry and Molecular Biology, The Pennsylvania State University, University Park, Pennsylvania 16802, United States
| | - Yin Song
- School of Optics and Photonics, Beijing Institute of Technology, 5 Zhongguancun South Street, Haidian District, Beijing, 100081, China
| | - Christopher J Gisriel
- Department of Chemistry, Yale University, New Haven, Connecticut 06520, United States
| | - Gary W Brudvig
- Department of Chemistry, Yale University, New Haven, Connecticut 06520, United States
| | - Donald A Bryant
- Department of Biochemistry and Molecular Biology, The Pennsylvania State University, University Park, Pennsylvania 16802, United States
| | - Jennifer P Ogilvie
- Department of Physics and Biophysics, University of Michigan, 450 Church Street, Ann Arbor, Michigan 48109, United States
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4
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Sirohiwal A, Pantazis DA. Reaction Center Excitation in Photosystem II: From Multiscale Modeling to Functional Principles. Acc Chem Res 2023; 56:2921-2932. [PMID: 37844298 PMCID: PMC10634305 DOI: 10.1021/acs.accounts.3c00392] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2023] [Indexed: 10/18/2023]
Abstract
Oxygenic photosynthesis is the fundamental energy-converting process that utilizes sunlight to generate molecular oxygen and the organic compounds that sustain life. Protein-pigment complexes harvest light and transfer excitation energy to specialized pigment assemblies, reaction centers (RC), where electron transfer cascades are initiated. A molecular-level understanding of the primary events is indispensable for elucidating the principles of natural photosynthesis and enabling development of bioinspired technologies. The primary enzyme in oxygenic photosynthesis is Photosystem II (PSII), a membrane-embedded multisubunit complex, that catalyzes the light-driven oxidation of water. The RC of PSII consists of four chlorophyll a and two pheophytin a pigments symmetrically arranged along two core polypeptides; only one branch participates in electron transfer. Despite decades of research, fundamental questions remain, including the origin of this functional asymmetry, the nature of primary charge-transfer states and the identity of the initial electron donor, the origin of the capability of PSII to enact charge separation with far-red photons, i.e., beyond the "red limit" where individual chlorophylls absorb, and the role of protein conformational dynamics in modulating charge-separation pathways.In this Account, we highlight developments in quantum-chemistry based excited-state computations for multipigment assemblies and the refinement of protocols for computing protein-induced electrochromic shifts and charge-transfer excitations calibrated with modern local correlation coupled cluster methods. We emphasize the importance of multiscale atomistic quantum-mechanics/molecular-mechanics and large-scale molecular dynamics simulations, which enabled direct and accurate modeling of primary processes in RC excitation at the quantum mechanical level.Our findings show how differential protein electrostatics enable spectral tuning of RC pigments and generate functional asymmetry in PSII. A chlorophyll pigment on the active branch (ChlD1) has the lowest site energy in PSII and is the primary electron donor. The complete absence of low-lying charge-transfer states within the central pair of chlorophylls excludes a long-held assumption about the initial charge separation. Instead, we identify two primary charge separation pathways, both with the same pheophytin acceptor (PheoD1): a fast pathway with ChlD1 as the primary electron donor (short-range charge-separation) and a slow pathway with PD1PD2 as the initial donor (long-range charge separation). The low-energy spectrum is dominated by two states with significant charge-transfer character, ChlD1δ+PheoD1δ- and PD1δ+PheoD1δ-. The conformational dynamics of PSII allows these charge-transfer states to span wide energy ranges, pushing oxygenic photosynthesis beyond the "red limit". These results provide a quantum mechanical picture of the primary events in the RC of oxygenic photosynthesis, forming a solid basis for interpreting experimental observations and for extending photosynthesis research in new directions.
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Affiliation(s)
- Abhishek Sirohiwal
- Department
of Biochemistry and Biophysics, Arrhenius Laboratory, Stockholm University, 10691 Stockholm, Sweden
| | - Dimitrios A. Pantazis
- Max-Planck-Institut
für Kohlenforschung, Kaiser-Wilhelm-Platz 1, 45470 Mülheim an der Ruhr, Germany
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5
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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: 9] [Impact Index Per Article: 9.0] [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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6
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Capone M, Sirohiwal A, Aschi M, Pantazis DA, Daidone I. Alternative Fast and Slow Primary Charge-Separation Pathways in Photosystem II. Angew Chem Int Ed Engl 2023; 62:e202216276. [PMID: 36791234 DOI: 10.1002/anie.202216276] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2022] [Revised: 01/23/2023] [Accepted: 02/13/2023] [Indexed: 02/17/2023]
Abstract
Photosystem-II (PSII) is a multi-subunit protein complex that harvests sunlight to perform oxygenic photosynthesis. Initial light-activated charge separation takes place at a reaction centre consisting of four chlorophylls and two pheophytins. Understanding the processes following light excitation remains elusive due to spectral congestion, the ultrafast nature, and multi-component behaviour of the charge-separation process. Here, using advanced computational multiscale approaches which take into account the large-scale configurational flexibility of the system, we identify two possible primary pathways to radical-pair formation that differ by three orders of magnitude in their kinetics. The fast (short-range) pathway is dominant, but the existence of an alternative slow (long-range) charge-separation pathway hints at the evolution of redundancy that may serve other purposes, adaptive or protective, related to formation of the unique oxidative species that drives water oxidation in PSII.
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Affiliation(s)
- Matteo Capone
- Department of Physical and Chemical Sciences, University of L'Aquila, via Vetoio (Coppito 1), 67010, L'Aquila, Italy
| | - Abhishek Sirohiwal
- Max-Planck-Institut für Kohlenforschung, Kaiser-Wilhelm-Platz 1, 45470, Mülheim an der Ruhr, Germany.,Present Address: Department of Biochemistry and Biophysics, Arrhenius Laboratory, Stockholm University, 10691, Stockholm, Sweden
| | - Massimiliano Aschi
- Department of Physical and Chemical Sciences, University of L'Aquila, via Vetoio (Coppito 1), 67010, L'Aquila, Italy
| | - Dimitrios A Pantazis
- Max-Planck-Institut für Kohlenforschung, Kaiser-Wilhelm-Platz 1, 45470, Mülheim an der Ruhr, Germany
| | - Isabella Daidone
- Department of Physical and Chemical Sciences, University of L'Aquila, via Vetoio (Coppito 1), 67010, L'Aquila, Italy
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7
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Nadtochenko V, Cherepanov D, Kochev S, Motyakin M, Kostrov A, Golub A, Antonova O, Kabachii Y, Rtimi S. Structural and optical properties of Mn2+-doped ZnCdS/ZnS core/shell quantum dots: New insights in Mn2+ localization for higher luminescence sensing. J Photochem Photobiol A Chem 2022. [DOI: 10.1016/j.jphotochem.2022.113946] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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8
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Yoneda Y, Arsenault EA, Yang SJ, Orcutt K, Iwai M, Fleming GR. The initial charge separation step in oxygenic photosynthesis. Nat Commun 2022; 13:2275. [PMID: 35477708 PMCID: PMC9046298 DOI: 10.1038/s41467-022-29983-1] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2021] [Accepted: 04/11/2022] [Indexed: 11/09/2022] Open
Abstract
Photosystem II is crucial for life on Earth as it provides oxygen as a result of photoinduced electron transfer and water splitting reactions. The excited state dynamics of the photosystem II-reaction center (PSII-RC) has been a matter of vivid debate because the absorption spectra of the embedded chromophores significantly overlap and hence it is extremely difficult to distinguish transients. Here, we report the two-dimensional electronic-vibrational spectroscopic study of the PSII-RC. The simultaneous resolution along both the visible excitation and infrared detection axis is crucial in allowing for the character of the excitonic states and interplay between them to be clearly distinguished. In particular, this work demonstrates that the mixed exciton-charge transfer state, previously proposed to be responsible for the far-red light operation of photosynthesis, is characterized by the ChlD1+Phe radical pair and can be directly prepared upon photoexcitation. Further, we find that the initial electron acceptor in the PSII-RC is Phe, rather than PD1, regardless of excitation wavelength. The photosystem II reaction center (PSII-RC) is a model system to understand the initial steps of photosynthesis, but its excited state dynamics is difficult to disentangle with most spectroscopic methods. Here the authors perform a two-dimensional electronic-vibrational spectroscopic study of PSII-RC, providing detailed insight into such dynamics and into the mechanism of charge separation.
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Affiliation(s)
- Yusuke Yoneda
- Department of Chemistry, University of California, Berkeley, CA, 94720, United States.,Molecular Biophysics and Integrated Bioimaging Division, Lawrence Berkeley National Laboratory, Berkeley, CA, 94720, United States.,Research Center of Integrative Molecular Systems, Institute for Molecular Science, National Institute of Natural Sciences, Okazaki, Aichi, 444-8585, Japan
| | - Eric A Arsenault
- Department of Chemistry, University of California, Berkeley, CA, 94720, United States.,Molecular Biophysics and Integrated Bioimaging Division, Lawrence Berkeley National Laboratory, Berkeley, CA, 94720, United States.,Kavli Energy Nanoscience Institute at Berkeley, Berkeley, CA, 94720, United States
| | - Shiun-Jr Yang
- Department of Chemistry, University of California, Berkeley, CA, 94720, United States.,Molecular Biophysics and Integrated Bioimaging Division, Lawrence Berkeley National Laboratory, Berkeley, CA, 94720, United States
| | - Kaydren Orcutt
- Department of Chemistry, University of California, Berkeley, CA, 94720, United States.,Molecular Biophysics and Integrated Bioimaging Division, Lawrence Berkeley National Laboratory, Berkeley, CA, 94720, United States
| | - Masakazu Iwai
- Molecular Biophysics and Integrated Bioimaging Division, Lawrence Berkeley National Laboratory, Berkeley, CA, 94720, United States.,Department of Plant and Microbial Biology, University of California, Berkeley, CA, 94720, United States
| | - Graham R Fleming
- Department of Chemistry, University of California, Berkeley, CA, 94720, United States. .,Molecular Biophysics and Integrated Bioimaging Division, Lawrence Berkeley National Laboratory, Berkeley, CA, 94720, United States. .,Kavli Energy Nanoscience Institute at Berkeley, Berkeley, CA, 94720, United States.
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9
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Sirohiwal A, Neese F, Pantazis DA. How Can We Predict Accurate Electrochromic Shifts for Biochromophores? A Case Study on the Photosynthetic Reaction Center. J Chem Theory Comput 2021; 17:1858-1873. [PMID: 33566610 PMCID: PMC8023663 DOI: 10.1021/acs.jctc.0c01152] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2020] [Indexed: 01/28/2023]
Abstract
Protein-embedded chromophores are responsible for light harvesting, excitation energy transfer, and charge separation in photosynthesis. A critical part of the photosynthetic apparatus are reaction centers (RCs), which comprise groups of (bacterio)chlorophyll and (bacterio)pheophytin molecules that transform the excitation energy derived from light absorption into charge separation. The lowest excitation energies of individual pigments (site energies) are key for understanding photosynthetic systems, and form a prime target for quantum chemistry. A major theoretical challenge is to accurately describe the electrochromic (Stark) shifts in site energies produced by the inhomogeneous electric field of the protein matrix. Here, we present large-scale quantum mechanics/molecular mechanics calculations of electrochromic shifts for the RC chromophores of photosystem II (PSII) using various quantum chemical methods evaluated against the domain-based local pair natural orbital (DLPNO) implementation of the similarity-transformed equation of motion coupled cluster theory with single and double excitations (STEOM-CCSD). We show that certain range-separated density functionals (ωΒ97, ωΒ97X-V, ωΒ2PLYP, and LC-BLYP) correctly reproduce RC site energy shifts with time-dependent density functional theory (TD-DFT). The popular CAM-B3LYP functional underestimates the shifts and is not recommended. Global hybrid functionals are too insensitive to the environment and should be avoided, while nonhybrid functionals are strictly nonapplicable. Among the applicable approximate coupled cluster methods, the canonical versions of CC2 and ADC(2) were found to deviate significantly from the reference results both for the description of the lowest excited state and for the electrochromic shifts. By contrast, their spin-component-scaled (SCS) and particularly the scale-opposite-spin (SOS) variants compare well with the reference DLPNO-STEOM-CCSD and the best range-separated DFT methods. The emergence of RC excitation asymmetry is discussed in terms of intrinsic and protein electrostatic potentials. In addition, we evaluate a minimal structural scaffold of PSII, the D1-D2-CytB559 RC complex often employed in experimental studies, and show that it would have the same site energy distribution of RC chromophores as the full PSII supercomplex, but only under the unlikely conditions that the core protein organization and cofactor arrangement remain identical to those of the intact enzyme.
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Affiliation(s)
- Abhishek Sirohiwal
- Max-Planck-Institut
für Kohlenforschung, Kaiser-Wilhelm-Platz 1, 45470 Mülheim an der Ruhr, Germany
- Fakultät
für Chemie und Biochemie, Ruhr-Universität
Bochum, 44780 Bochum, Germany
| | - Frank Neese
- Max-Planck-Institut
für Kohlenforschung, Kaiser-Wilhelm-Platz 1, 45470 Mülheim an der Ruhr, Germany
| | - Dimitrios A. Pantazis
- Max-Planck-Institut
für Kohlenforschung, Kaiser-Wilhelm-Platz 1, 45470 Mülheim an der Ruhr, Germany
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10
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Sirohiwal A, Neese F, Pantazis DA. Protein Matrix Control of Reaction Center Excitation in Photosystem II. J Am Chem Soc 2020; 142:18174-18190. [PMID: 33034453 PMCID: PMC7582616 DOI: 10.1021/jacs.0c08526] [Citation(s) in RCA: 34] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2020] [Indexed: 02/06/2023]
Abstract
Photosystem II (PSII) is a multisubunit pigment-protein complex that uses light-induced charge separation to power oxygenic photosynthesis. Its reaction center chromophores, where the charge transfer cascade is initiated, are arranged symmetrically along the D1 and D2 core polypeptides and comprise four chlorophyll (PD1, PD2, ChlD1, ChlD2) and two pheophytin molecules (PheoD1 and PheoD2). Evolution favored productive electron transfer only via the D1 branch, with the precise nature of primary excitation and the factors that control asymmetric charge transfer remaining under investigation. Here we present a detailed atomistic description for both. We combine large-scale simulations of membrane-embedded PSII with high-level quantum-mechanics/molecular-mechanics (QM/MM) calculations of individual and coupled reaction center chromophores to describe reaction center excited states. We employ both range-separated time-dependent density functional theory and the recently developed domain based local pair natural orbital (DLPNO) implementation of the similarity transformed equation of motion coupled cluster theory with single and double excitations (STEOM-CCSD), the first coupled cluster QM/MM calculations of the reaction center. We find that the protein matrix is exclusively responsible for both transverse (chlorophylls versus pheophytins) and lateral (D1 versus D2 branch) excitation asymmetry, making ChlD1 the chromophore with the lowest site energy. Multipigment calculations show that the protein matrix renders the ChlD1 → PheoD1 charge-transfer the lowest energy excitation globally within the reaction center, lower than any pigment-centered local excitation. Remarkably, no low-energy charge transfer states are located within the "special pair" PD1-PD2, which is therefore excluded as the site of initial charge separation in PSII. Finally, molecular dynamics simulations suggest that modulation of the electrostatic environment due to protein conformational flexibility enables direct excitation of low-lying charge transfer states by far-red light.
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Affiliation(s)
- Abhishek Sirohiwal
- Max-Planck-Institut
für Kohlenforschung, Kaiser-Wilhelm-Platz 1, 45470 Mülheim an der Ruhr, Germany
- Fakultät
für Chemie und Biochemie, Ruhr-Universität
Bochum, 44780 Bochum, Germany
| | - Frank Neese
- Max-Planck-Institut
für Kohlenforschung, Kaiser-Wilhelm-Platz 1, 45470 Mülheim an der Ruhr, Germany
| | - Dimitrios A. Pantazis
- Max-Planck-Institut
für Kohlenforschung, Kaiser-Wilhelm-Platz 1, 45470 Mülheim an der Ruhr, Germany
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11
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Evidence that chlorophyll f functions solely as an antenna pigment in far-red-light photosystem I from Fischerella thermalis PCC 7521. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2020; 1861:148184. [PMID: 32179058 DOI: 10.1016/j.bbabio.2020.148184] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/25/2019] [Revised: 02/21/2020] [Accepted: 03/09/2020] [Indexed: 11/20/2022]
Abstract
The Photosystem I (PSI) reaction center in cyanobacteria is comprised of ~96 chlorophyll (Chl) molecules, including six specialized Chl molecules denoted Chl1A/Chl1B (P700), Chl2A/Chl2B, and Chl3A/Chl3B that are arranged in two branches and function in primary charge separation. It has recently been proposed that PSI from Chroococcidiopsis thermalis (Nürnberg et al. (2018) Science 360, 1210-1213) and Fischerella thermalis PCC 7521 (Hastings et al. (2019) Biochim. Biophys. Acta 1860, 452-460) contain Chl f in the positions Chl2A/Chl2B. We tested this proposal by exciting RCs from white-light grown (WL-PSI) and far-red light grown (FRL-PSI) F. thermalis PCC 7521 with femtosecond pulses and analyzing the optical dynamics. If Chl f were in the position Chl2A/Chl2B in FRL-PSI, excitation at 740 nm should have produced the charge-separated state P700+A0- followed by electron transfer to A1 with a τ of ≤25 ps. Instead, it takes ~230 ps for the charge-separated state to develop because the excitation migrates uphill from Chl f in the antenna to the trapping center. Further, we observe a strong electrochromic shift at 685 nm in the final P700+A1- spectrum that can only be explained if Chl a is in the positions Chl2A/Chl2B. Similar arguments rule out the presence of Chl f in the positions Chl3A/Chl3B; hence, Chl f is likely to function solely as an antenna pigment in FRL-PSI. We additionally report the presence of an excitonically coupled homo- or heterodimer of Chl f absorbing around 790 nm that is kinetically independent of the Chl f population that absorbs around 740 nm.
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Cherepanov DA, Gostev FE, Shelaev IV, Denisov NN, Nadtochenko VA. Monitoring the electric field in CdSe quantum dots under ultrafast interfacial electron transfer via coherent phonon dynamics. NANOSCALE 2018; 10:22409-22419. [PMID: 30475371 DOI: 10.1039/c8nr07644h] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Coherent phonon dynamics in CdSe quantum dots (QD) under an ultrafast electron transfer (ET) reaction of the (1Se-1S3/2) exciton quenched by methyl viologen (MV2+) adsorbed onto the QD surface was studied by ultrafast pump-probe spectroscopy. Frequency and amplitude modulations (FM, AM) of the transient absorption ΔA(ωprobe,t) in the pure CdSe and coupled CdSe/MV2+ QDs were identified in the bleach band dynamics of the red-edge exciton. The fast Fourier transform (FFT) and continuous wavelet transform analysis of the FM and AM oscillations revealed peaks at 0.51-0.58 THz (17-19 cm-1) and 6.06-6.27 THz (202-209 cm-1) attributed to the longitudinal acoustic (LA) and longitudinal optical (LO) phonons, respectively. The electron transfer to MV2+ proceeded non-exponentially with effective time constants of 164 fs (∼30%) and 540 fs (∼70%). The quantum yield of MV˙+ radical formation was 40 ± 5%. It implies a fast route for the electron-hole pair [h+…MV˙+] recombination that can be rationalized in accordance with the adiabatic ET mechanism at the semiconductor surface. In the coupled CdSe/MV2+ QDs, the amplitude of the FM oscillations rose considerably with time despite the natural attenuation of the phonon amplitude due to decoherence processes. A kinetic model explaining the increase of FM oscillations is proposed. The surprising growth of FM oscillations is elucidated by the kinetic model taking into account the relatively slow damping of LO phonon oscillations (∼1.5 ps), the ultrafast ET to MV2+, and the quantum yield of charge separation [h+…MV˙+] (∼40%). The fast formation of the charge-separated pair [h+…MV˙+] suggests the appearance of an electric field F with a strength of ∼3 × 106 V cm-1. The MV2+ reduction substantially increased the magnitude of LA phonon oscillations. Since the ET time is shorter than the period of LA phonon oscillations (∼1.8 ps), the MV2+ reduction substantially increased the magnitude of LA phonon oscillations due to the inverse piezoelectric effect. The CdSe nanocrystals exposed to the electric field F exhibit the quantum-confined Stark and Franz-Keldysh electro-absorption effects. The proposed kinetic model gives consideration to the dynamic Stark shift of the red-edge exciton and to the increased amplitude of LO phonon oscillations in the bleach band dynamics.
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Affiliation(s)
- Dmitry A Cherepanov
- N.Semenov Institute of Chemical Physics Russian Academy of Sciences, Kosigin str.4, Moscow, 119991, Russia.
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Nadtochenko V, Denisov N, Aybush A, Gostev F, Shelaev I, Titov A, Umanskiy S, Cherepanov AD. Ultrafast Spectroscopy of Fano-Like Resonance between Optical Phonon and Excitons in CdSe Quantum Dots: Dependence of Coherent Vibrational Wave-Packet Dynamics on Pump Fluence. NANOMATERIALS 2017; 7:nano7110371. [PMID: 29113056 PMCID: PMC5707588 DOI: 10.3390/nano7110371] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/08/2017] [Revised: 10/25/2017] [Accepted: 10/27/2017] [Indexed: 11/16/2022]
Abstract
The main goal of the present work is to study the coherent phonon in strongly confined CdSe quantum dots (QDs) under varied pump fluences. The main characteristics of coherent phonons (amplitude, frequency, phase, spectrogram) of CdSe QDs under the red-edge pump of the excitonic band [1S(e)-1S3/2(h)] are reported. We demonstrate for the first time that the amplitude of the coherent optical longitudinal-optical (LO) phonon at 6.16 THz excited in CdSe nanoparticles by a femtosecond unchirped pulse shows a non-monotone dependence on the pump fluence. This dependence exhibits the maximum at pump fluence ~0.8 mJ/cm2. At the same time, the amplitudes of the longitudinal acoustic (LA) phonon mode at 0.55 THz and of the coherent wave packet of toluene at 15.6, 23.6 THz show a monotonic rise with the increase of pump fluence. The time frequency representation of an oscillating signal corresponding to LO phonons revealed by continuous wavelet transform (CWT) shows a profound destructive quantum interference close to the origin of distinct (optical phonon) and continuum-like (exciton) quasiparticles. The CWT spectrogram demonstrates a nonlinear chirp at short time delays, where the chirp sign depends on the pump pulse fluence. The CWT spectrogram reveals an anharmonic coupling between optical and acoustic phonons.
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Affiliation(s)
- Victor Nadtochenko
- N.N. Semenov Institute of Chemical Physics, Russian Academy of Sciences, Kosygina st., 4, 119991 Moscow, Russia.
- Institute of Problem of Chemical Physics, Russian Academy of Sciences, 142432 Chernogolovka, Russia.
- Chemical Faculty, Moscow State University, Leninskie Gory, 119992 Moscow, Russia.
| | - Nikolay Denisov
- Institute of Problem of Chemical Physics, Russian Academy of Sciences, 142432 Chernogolovka, Russia.
| | - Arseniy Aybush
- N.N. Semenov Institute of Chemical Physics, Russian Academy of Sciences, Kosygina st., 4, 119991 Moscow, Russia.
| | - Fedor Gostev
- N.N. Semenov Institute of Chemical Physics, Russian Academy of Sciences, Kosygina st., 4, 119991 Moscow, Russia.
| | - Ivan Shelaev
- N.N. Semenov Institute of Chemical Physics, Russian Academy of Sciences, Kosygina st., 4, 119991 Moscow, Russia.
| | - Andrey Titov
- N.N. Semenov Institute of Chemical Physics, Russian Academy of Sciences, Kosygina st., 4, 119991 Moscow, Russia.
| | - Stanislav Umanskiy
- N.N. Semenov Institute of Chemical Physics, Russian Academy of Sciences, Kosygina st., 4, 119991 Moscow, Russia.
| | - And Dmitry Cherepanov
- N.N. Semenov Institute of Chemical Physics, Russian Academy of Sciences, Kosygina st., 4, 119991 Moscow, Russia.
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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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Paschenko VZ, Churin AA, Gorokhov VV, Grishanova NP, Korvatovskii BN, Maksimov EG, Mamedov MD. The efficiency of non-photochemical fluorescence quenching by cation radicals in photosystem II reaction centers. PHOTOSYNTHESIS RESEARCH 2016; 130:325-333. [PMID: 27075994 DOI: 10.1007/s11120-016-0260-z] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/15/2016] [Accepted: 04/04/2016] [Indexed: 06/05/2023]
Abstract
In a direct experiment, the rate constants of photochemical k p and non-photochemical k p+ quenching of the chlorophyll fluorescence have been determined in spinach photosystem II (PS II) membrane fragments, oxygen-evolving PS II core, as well as manganese-depleted PS II particles using pulse fluorimetry. In the dark-adapted reaction center(s) (RC), the fluorescence decay kinetics of the antenna were measured at low-intensity picosecond pulsed excitation. To create a "closed" P680+Q A- state, RCs were illuminated by high-intensity actinic flash 8 ns prior to the measuring flash. The obtained data were approximated by the sum of two decaying exponents. It was found that the antennae fluorescence quenching efficiency by the oxidized photoactive pigment of RC P680+ was about 1.5 times higher than that of the neutral P680 state. These results were confirmed by a single-photon counting technique, which allowed to resolve the additional slow component of the fluorescence decay. Slow component was assigned to the charge recombination of P680+Pheo- in PS II RC. Thus, for the first time, the ratio k p+ /k p ≅ 1.5 was found directly. The mechanism of the higher efficiency of non-photochemical quenching comparing to photochemical quenching is discussed.
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Affiliation(s)
- V Z Paschenko
- Biophysical Department, Faculty of Biology, M.V.Lomonosov Moscow State University, Leninskye Gory 1, Build. 12, Moscow, Russia, 119234.
| | - A A Churin
- Biophysical Department, Faculty of Biology, M.V.Lomonosov Moscow State University, Leninskye Gory 1, Build. 12, Moscow, Russia, 119234
| | - V V Gorokhov
- Biophysical Department, Faculty of Biology, M.V.Lomonosov Moscow State University, Leninskye Gory 1, Build. 12, Moscow, Russia, 119234
| | - N P Grishanova
- Biophysical Department, Faculty of Biology, M.V.Lomonosov Moscow State University, Leninskye Gory 1, Build. 12, Moscow, Russia, 119234
| | - B N Korvatovskii
- Biophysical Department, Faculty of Biology, M.V.Lomonosov Moscow State University, Leninskye Gory 1, Build. 12, Moscow, Russia, 119234
| | - E G Maksimov
- Biophysical Department, Faculty of Biology, M.V.Lomonosov Moscow State University, Leninskye Gory 1, Build. 12, Moscow, Russia, 119234
| | - M D Mamedov
- A.N.Belozersky Institute of Physico-Chemical Biology, Moscow State University, Leninskye Gory 1, Build. 40, Moscow, Russia, 119992
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Najafpour MM, Renger G, Hołyńska M, Moghaddam AN, Aro EM, Carpentier R, Nishihara H, Eaton-Rye JJ, Shen JR, Allakhverdiev SI. Manganese Compounds as Water-Oxidizing Catalysts: From the Natural Water-Oxidizing Complex to Nanosized Manganese Oxide Structures. Chem Rev 2016; 116:2886-936. [PMID: 26812090 DOI: 10.1021/acs.chemrev.5b00340] [Citation(s) in RCA: 332] [Impact Index Per Article: 41.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
All cyanobacteria, algae, and plants use a similar water-oxidizing catalyst for water oxidation. This catalyst is housed in Photosystem II, a membrane-protein complex that functions as a light-driven water oxidase in oxygenic photosynthesis. Water oxidation is also an important reaction in artificial photosynthesis because it has the potential to provide cheap electrons from water for hydrogen production or for the reduction of carbon dioxide on an industrial scale. The water-oxidizing complex of Photosystem II is a Mn-Ca cluster that oxidizes water with a low overpotential and high turnover frequency number of up to 25-90 molecules of O2 released per second. In this Review, we discuss the atomic structure of the Mn-Ca cluster of the Photosystem II water-oxidizing complex from the viewpoint that the underlying mechanism can be informative when designing artificial water-oxidizing catalysts. This is followed by consideration of functional Mn-based model complexes for water oxidation and the issue of Mn complexes decomposing to Mn oxide. We then provide a detailed assessment of the chemistry of Mn oxides by considering how their bulk and nanoscale properties contribute to their effectiveness as water-oxidizing catalysts.
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Affiliation(s)
| | - Gernot Renger
- Institute of Chemistry, Max-Volmer-Laboratory of Biophysical Chemistry, Technical University Berlin , Straße des 17. Juni 135, D-10623 Berlin, Germany
| | - Małgorzata Hołyńska
- Fachbereich Chemie und Wissenschaftliches Zentrum für Materialwissenschaften (WZMW), Philipps-Universität Marburg , Hans-Meerwein-Straße, D-35032 Marburg, Germany
| | | | - Eva-Mari Aro
- Department of Biochemistry and Food Chemistry, University of Turku , 20014 Turku, Finland
| | - Robert Carpentier
- Groupe de Recherche en Biologie Végétale (GRBV), Université du Québec à Trois-Rivières , C.P. 500, Trois-Rivières, Québec G9A 5H7, Canada
| | - Hiroshi Nishihara
- Department of Chemistry, School of Science, The University of Tokyo , 7-3-1, Hongo, Bunkyo-Ku, Tokyo 113-0033, Japan
| | - Julian J Eaton-Rye
- Department of Biochemistry, University of Otago , P.O. Box 56, Dunedin 9054, New Zealand
| | - Jian-Ren Shen
- Photosynthesis Research Center, Graduate School of Natural Science and Technology, Faculty of Science, Okayama University , Okayama 700-8530, Japan.,Photosynthesis Research Center, Key Laboratory of Photobiology, Institute of Botany, Chinese Academy of Sciences , Beijing 100093, China
| | - Suleyman I Allakhverdiev
- Controlled Photobiosynthesis Laboratory, Institute of Plant Physiology, Russian Academy of Sciences , Botanicheskaya Street 35, Moscow 127276, Russia.,Institute of Basic Biological Problems, Russian Academy of Sciences , Pushchino, Moscow Region 142290, Russia.,Department of Plant Physiology, Faculty of Biology, M.V. Lomonosov Moscow State University , Leninskie Gory 1-12, Moscow 119991, Russia
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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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Spectral and Luminescence Properties of Lanthanide(III) Complexes with Porphyrins and Corroles with Varied Structure. THEOR EXP CHEM+ 2015. [DOI: 10.1007/s11237-015-9420-z] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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Mamedov M, Nadtochenko V, Semenov A. Primary electron transfer processes in photosynthetic reaction centers from oxygenic organisms. PHOTOSYNTHESIS RESEARCH 2015; 125:51-63. [PMID: 25648636 DOI: 10.1007/s11120-015-0088-y] [Citation(s) in RCA: 68] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/17/2014] [Accepted: 01/12/2015] [Indexed: 05/22/2023]
Abstract
This minireview is written in honor of Vladimir A. Shuvalov, a pioneer in the area of primary photochemistry of both oxygenic and anoxygenic photosyntheses (See a News Report: Allakhverdiev et al. 2014). In the present paper, we describe the current state of the formation of the primary and secondary ion-radical pairs within photosystems (PS) II and I in oxygenic organisms. Spectral-kinetic studies of primary events in PS II and PS I, upon excitation by ~20 fs laser pulses, are now available and reviewed here; for PS II, excitation was centered at 710 nm, and for PS I, it was at 720 nm. In PS I, conditions were chosen to maximally increase the relative contribution of the direct excitation of the reaction center (RC) in order to separate the kinetics of the primary steps of charge separation in the RC from that of the excitation energy transfer in the antenna. Our results suggest that the sequence of the primary electron transfer reactions is P680 → ChlD1 → PheD1 → QA (PS II) and P700 → A 0A/A 0B → A 1A/A 1B (PS I). However, alternate routes of charge separation in PS II, under different excitation conditions, are not ruled out.
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Affiliation(s)
- Mahir Mamedov
- A.N. Belozersky Institute of Physical-Chemical Biology, Moscow State University, 119991, Moscow, Russia,
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Shuvalov VA. My journey in photosynthesis research. PHOTOSYNTHESIS RESEARCH 2015; 125:5-8. [PMID: 25645566 DOI: 10.1007/s11120-015-0077-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/24/2014] [Accepted: 01/05/2015] [Indexed: 06/04/2023]
Abstract
At the invitation of Suleyman I. Allakhverdiev, I provide here a brief autobiography for this special issue that recognizes my service and research for the larger international community of photosynthesis research.
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Affiliation(s)
- Vladimir A Shuvalov
- Institute of Basic Biological Problems, RAS, 142290, Pushchino, Moscow Region, Russia,
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Nadtochenko VA, Shelaev IV, Mamedov MD, Shkuropatov AY, Semenov AY, Shuvalov VA. Primary radical ion pairs in photosystem II core complexes. BIOCHEMISTRY (MOSCOW) 2014; 79:197-204. [PMID: 24821445 DOI: 10.1134/s0006297914030043] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Ultrafast absorption spectroscopy with 20-fs resolution was applied to study primary charge separation in spinach photosystem II (PSII) reaction center (RC) and PSII core complex (RC complex with integral antenna) upon excitation at maximum wavelength 700-710 nm at 278 K. It was found that the initial charge separation between P680* and ChlD1 (Chl-670) takes place with a time constant of ~1 ps with the formation of the primary charge-separated state P680* with an admixture of: P680*((1-δ)) (P680(δ+)ChlD1(δ-)), where δ ~ 0.5. The subsequent electron transfer from P680(δ+)ChlD1(δ-) to pheophytin (Pheo) occurs within 13 ps and is accompanied by a relaxation of the absorption band at 670 nm (ChlD1(δ-)) and bleaching of the PheoD1 bands at 420, 545, and 680 nm with development of the Pheo(-) band at 460 nm. Further electron transfer to QA occurs within 250 ps in accordance with earlier data. The spectra of P680(+) and Pheo(-) formation include a bleaching band at 670 nm; this indicates that Chl-670 is an intermediate between P680 and Pheo. Stimulated emission kinetics at 685 nm demonstrate the existence of two decaying components with time constants of ~1 and ~13 ps due to the formation of P680(δ+)ChlD1(δ-) and P680(+)PheoD1(-), respectively.
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Affiliation(s)
- V A Nadtochenko
- Semenov Institute of Chemical Physics, Russian Academy of Sciences, Moscow, 119991, Russia
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Allakhverdiev SI, Tomo T. International conference on "Photosynthesis Research for Sustainability-2014: in honor of Vladimir A. Shuvalov", held on June 2-7, 2014, in Pushchino, Russia. PHOTOSYNTHESIS RESEARCH 2014; 122:337-347. [PMID: 25214184 DOI: 10.1007/s11120-014-0032-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
In this article, we provide a News Report on an international conference "Photosynthesis Research for Sustainability-2014" that was held in honor of Vladimir A. Shuvalov at the Biological Research Center of the Russian Academy of Sciences, in Pushchino, Russia, during June 2-7, 2014 (http://photosynthesis2014.cellreg.org/). We begin this report with a short description of Vladimir A. Shuvalov, the honored scientist. We then provide some information on the conference, and the program. A special feature of this conference was awards given to nine young investigators; they are recognized in this Report. We have also included several photographs to show the pleasant ambiance at this conference. We invite the readers to the next two conferences on ''Photosynthesis Research for Sustainability-2015: the first one to be held in Baku in May or June, 2015, and the second one, which will honor George C. Papageorgiou, will be held in Greece (in Colymbari, near Chania in Crete) during September 21-26, 2015. Information will be posted at: http://photosynthesis2015.cellreg.org/.
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Affiliation(s)
- Suleyman I Allakhverdiev
- Institute of Plant Physiology, Russian Academy of Sciences, Botanicheskaya Street 35, Moscow, 127276, Russia,
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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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Vibronic coherence in oxygenic photosynthesis. Nat Chem 2014; 6:706-11. [DOI: 10.1038/nchem.2005] [Citation(s) in RCA: 303] [Impact Index Per Article: 30.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2014] [Accepted: 06/16/2014] [Indexed: 01/05/2023]
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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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Kaminskaya OP, Shuvalov VA. Biphasic reduction of cytochrome b559 by plastoquinol in photosystem II membrane fragments: evidence for two types of cytochrome b559/plastoquinone redox equilibria. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2013; 1827:471-83. [PMID: 23357332 DOI: 10.1016/j.bbabio.2013.01.007] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/19/2012] [Revised: 01/14/2013] [Accepted: 01/16/2013] [Indexed: 10/27/2022]
Abstract
In photosystem II membrane fragments with oxidized cytochrome (Cyt) b559 reduction of Cyt b559 by plastoquinol formed in the membrane pool under illumination and by exogenous decylplastoquinol added in the dark was studied. Reduction of oxidized Cyt b559 by plastoquinols proceeds biphasically comprising a fast component with a rate constant higher than (10s)(-1), named phase I, followed by a slower dark reaction with a rate constant of (2.7min)(-1) at pH6.5, termed phase II. The extents of both components of Cyt b559 reduction increased with increasing concentrations of the quinols, with that, maximally a half of oxidized Cyt b559 can be photoreduced or chemically reduced in phase I at pH6.5. The photosystem II herbicide dinoseb but not 3-(3,4-dichlorophenyl)-1,1-dimethylurea (DCMU) competed with the quinol reductant in phase I. The results reveal that the two components of the Cyt b559 redox reaction reflect two redox equilibria attaining in different time domains. One-electron redox equilibrium between oxidized Cyt b559 and the photosystem II-bound plastoquinol is established in phase I of Cyt b559 reduction. Phase II is attributed to equilibration of Cyt b559 redox forms with the quinone pool. The quinone site involved in phase I of Cyt b559 reduction is considered to be the site regulating the redox potential of Cyt b559 which can accommodate quinone, semiquinone and quinol forms. The properties of this site designated here as QD clearly suggest that it is distinct from the site QC found in the photosystem II crystal structure.
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Affiliation(s)
- Olga P Kaminskaya
- Institute of Basic Biological Problems, Russian Academy of Sciences, Pushchino, Moscow Region 142290, Russia.
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Nadtochenko VA, Smitienko OA, Feldman TB, Mozgovaya MN, Shelaev IV, Gostev FE, Sarkisov OM, Ostrovsky MA. Conical intersection participation in femtosecond dynamics of visual pigment rhodopsin chromophore cis-trans photoisomerization. DOKL BIOCHEM BIOPHYS 2012; 446:242-6. [DOI: 10.1134/s1607672912050080] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2012] [Indexed: 11/22/2022]
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Acharya K, Neupane B, Zazubovich V, Sayre RT, Picorel R, Seibert M, Jankowiak R. Site energies of active and inactive pheophytins in the reaction center of Photosystem II from Chlamydomonas reinhardtii. J Phys Chem B 2012; 116:3890-9. [PMID: 22397491 DOI: 10.1021/jp3007624] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
It is widely accepted that the primary electron acceptor in various Photosystem II (PSII) reaction center (RC) preparations is pheophytin a (Pheo a) within the D1 protein (Pheo(D1)), while Pheo(D2) (within the D2 protein) is photochemically inactive. The Pheo site energies, however, have remained elusive, due to inherent spectral congestion. While most researchers over the past two decades placed the Q(y)-states of Pheo(D1) and Pheo(D2) bands near 678-684 and 668-672 nm, respectively, recent modeling [Raszewski et al. Biophys. J. 2005, 88, 986 - 998; Cox et al. J. Phys. Chem. B 2009, 113, 12364 - 12374] of the electronic structure of the PSII RC reversed the assignment of the active and inactive Pheos, suggesting that the mean site energy of Pheo(D1) is near 672 nm, whereas Pheo(D2) (~677.5 nm) and Chl(D1) (~680 nm) have the lowest energies (i.e., the Pheo(D2)-dominated exciton is the lowest excited state). In contrast, chemical pigment exchange experiments on isolated RCs suggested that both pheophytins have their Q(y) absorption maxima at 676-680 nm [Germano et al. Biochemistry 2001, 40, 11472 - 11482; Germano et al. Biophys. J. 2004, 86, 1664 - 1672]. To provide more insight into the site energies of both Pheo(D1) and Pheo(D2) (including the corresponding Q(x) transitions, which are often claimed to be degenerate at 543 nm) and to attest that the above two assignments are most likely incorrect, we studied a large number of isolated RC preparations from spinach and wild-type Chlamydomonas reinhardtii (at different levels of intactness) as well as the Chlamydomonas reinhardtii mutant (D2-L209H), in which the active branch Pheo(D1) is genetically replaced with chlorophyll a (Chl a). We show that the Q(x)-/Q(y)-region site energies of Pheo(D1) and Pheo(D2) are ~545/680 nm and ~541.5/670 nm, respectively, in good agreement with our previous assignment [Jankowiak et al. J. Phys. Chem. B 2002, 106, 8803 - 8814]. The latter values should be used to model excitonic structure and excitation energy transfer dynamics of the PSII RCs.
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Affiliation(s)
- K Acharya
- Department of Chemistry, Kansas State University, Manhattan, Kansas 66506, United States
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Femtosecond dynamics of photocyclization of 1-[(4-{5-[4-chloromethyl-2,5-dimethyl-3-thienyl]-2-oxo-1,3-dioxol-4-yl}-2,5-dimethyl-3-thienyl)methyl]pyridinium chloride. Russ Chem Bull 2012. [DOI: 10.1007/s11172-011-0176-x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/14/2022]
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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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Renger T, Schlodder E. Optical properties, excitation energy and primary charge transfer in photosystem II: theory meets experiment. JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY B-BIOLOGY 2011; 104:126-41. [PMID: 21531572 DOI: 10.1016/j.jphotobiol.2011.03.016] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/23/2010] [Revised: 03/04/2011] [Accepted: 03/21/2011] [Indexed: 11/29/2022]
Abstract
In this review we discuss structure-function relationships of the core complex of photosystem II, as uncovered from analysis of optical spectra of the complex and its subunits. Based on descriptions of optical difference spectra including site directed mutagenesis we propose a revision of the multimer model of the symmetrically arranged reaction center pigments, described by an asymmetric exciton Hamiltonian. Evidence is provided for the location of the triplet state, the identity of the primary electron donor, the localization of the cation and the secondary electron transfer pathway in the reaction center. We also discuss the stationary and time-dependent optical properties of the CP43 and CP47 subunits and the excitation energy transfer and trapping-by-charge-transfer kinetics in the core complex.
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Affiliation(s)
- Thomas Renger
- Institut für Theoretische Physik, Johannes Kepler Universität, Abteilung Theoretische Biophysik, Austria.
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Semenov AY, Kurashov VN, Mamedov MD. Transmembrane charge transfer in photosynthetic reaction centers: some similarities and distinctions. JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY B-BIOLOGY 2011; 104:326-32. [PMID: 21356596 DOI: 10.1016/j.jphotobiol.2011.02.004] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/22/2010] [Revised: 02/02/2011] [Accepted: 02/03/2011] [Indexed: 12/17/2022]
Abstract
This mini review presents a general comparison of structural and functional peculiarities of three types of photosynthetic reaction centers (RCs)--photosystem (PS) II, RC from purple bacteria (bRC) and PS I. The nature and mechanisms of the primary electron transfer reactions, as well as specific features of the charge transfer reactions at the donor and acceptor sides of RCs are considered. Comparison of photosynthetic RCs shows general similarity between the core central parts of all three types, between the acceptor sides of bRC and PS II, and between the donor sides of bRC and PS I. In the latter case, the similarity covers thermodynamic, kinetic and dielectric properties, which determine the resemblance of mechanisms of electrogenic reduction of the photooxidized primary donors. Significant distinctions between the donor and acceptor sides of PS I and PS II are also discussed. The results recently obtained in our laboratory indicate in favor of the following sequence of the primary and secondary electron transfer reactions: in PS II (bRC): Р(680)(Р(870)) → Chl(D1)(В(А)) → Phe(bPhe) → Q(A); and in PS I: Р(700) → А(0А)/A(0B) → Q(A)/Q(B).
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Affiliation(s)
- Alexey Yu Semenov
- A.N. Belozersky Institute of Physical-Chemical Biology, Moscow State University, 119992 Moscow, Leninskie Gory, Russia.
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Novoderezhkin VI, Romero E, Dekker JP, van Grondelle R. Multiple charge-separation pathways in photosystem II: modeling of transient absorption kinetics. Chemphyschem 2011; 12:681-8. [PMID: 21322104 DOI: 10.1002/cphc.201000830] [Citation(s) in RCA: 91] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2011] [Revised: 01/17/2011] [Indexed: 11/11/2022]
Abstract
We explain the transient absorption kinetics (E. Romero, I. H. M. van Stokkum, V. I. Novoderezhkin, J. P. Dekker, R. van Grondelle, Biochemistry 2010, 49, 4300) measured for isolated reaction centers of photosystem II at 77 K upon excitation of the primary donor band (680 nm). The excited-state dynamics is modeled on the basis of the exciton states of 6 cofactors coupled to 4 charge-transfer (CT) states. One CT state (corresponding to charge separation within the special pair) is supposed to be strongly coupled with the excited states, whereas the other radical pairs are supposed to be localized. Relaxation within the strongly coupled manifold and transfer to localized CT's are described by the modified Redfield and generalized Förster theories, respectively. A simultaneous and quantitative fit of the 680, 545, and 460 nm kinetics (corresponding to respectively the Q(y) transitions of the red-most cofactors, Q(x) transition of pheophytin, and pheophytin anion absorption) enables us to define the pathways and time scales of primary electron transfer. A consistent modeling of the data is only possible with a Scheme where charge separation occurs from both the accessory chlorophyll and from the special pair, giving rise to fast and slow components of the pheophytin anion formation, respectively.
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Affiliation(s)
- Vladimir I Novoderezhkin
- Institute of Physico-Chemical Biology, Moscow State University, Leninsky Gory, 119992, Moscow, Russia
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Mozgovaya MN, Smitienko OA, Shelaev IV, Gostev FE, Feldman TB, Nadtochenko VA, Sarkisov OM, Ostrovsky MA. Photochromism of visual pigment rhodopsin on the femtosecond time scale: Coherent control of retinal chromophore isomerization. DOKL BIOCHEM BIOPHYS 2010; 435:302-6. [DOI: 10.1134/s1607672910060062] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2010] [Indexed: 11/23/2022]
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Femtosecond primary charge separation in Synechocystis sp. PCC 6803 photosystem I. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2010; 1797:1410-20. [PMID: 20219440 DOI: 10.1016/j.bbabio.2010.02.026] [Citation(s) in RCA: 78] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/27/2009] [Revised: 01/25/2010] [Accepted: 02/23/2010] [Indexed: 11/21/2022]
Abstract
The ultrafast (<100 fs) conversion of delocalized exciton into charge-separated state between the primary donor P700 (bleaching at 705 nm) and the primary acceptor A0 (bleaching at 690 nm) in photosystem I (PS I) complexes from Synechocystis sp. PCC 6803 was observed. The data were obtained by application of pump-probe technique with 20-fs low-energy pump pulses centered at 720 nm. The earliest absorbance changes (close to zero delay) with a bleaching at 690 nm are similar to the product of the absorption spectrum of PS I complex and the laser pulse spectrum, which represents the efficiency spectrum of the light absorption by PS I upon femtosecond excitation centered at 720 nm. During the first approximately 60 fs the energy transfer from the chlorophyll (Chl) species bleaching at 690 nm to the Chl bleaching at 705 nm occurs, resulting in almost equal bleaching of the two forms with the formation of delocalized exciton between 690-nm and 705-nm Chls. Within the next approximately 40 fs the formation of a new broad band centered at approximately 660 nm (attributed to the appearance of Chl anion radical) is observed. This band decays with time constant simultaneously with an electron transfer to A1 (phylloquinone). The subtraction of kinetic difference absorption spectra of the closed (state P700+A0A1) PS I reaction center (RC) from that of the open (state P700A0A1) RC reveals the pure spectrum of the P700+A0- ion-radical pair. The experimental data were analyzed using a simple kinetic scheme: An*-->k1[(PA0)*A1--><100 fs P+A0-A1]-->k2P+A0A1-, and a global fitting procedure based on the singular value decomposition analysis. The calculated kinetics of transitions between intermediate states and their spectra were similar to the kinetics recorded at 694 and 705 nm and the experimental spectra obtained by subtraction of the spectra of closed RCs from the spectra of open RCs. As a result, we found that the main events in RCs of PS I under our experimental conditions include very fast (<100 fs) charge separation with the formation of the P700+A0-A1 state in approximately one half of the RCs, the approximately 5-ps energy transfer from antenna Chl* to P700A0A1 in the remaining RCs, and approximately 25-ps formation of the secondary radical pair P700+A0A1-.
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Smitienko OA, Mozgovaya MN, Shelaev IV, Gostev FE, Feldman TB, Nadtochenko VA, Sarkisov OM, Ostrovsky MA. Femtosecond formation dynamics of primary photoproducts of visual pigment rhodopsin. BIOCHEMISTRY (MOSCOW) 2010; 75:25-35. [DOI: 10.1134/s0006297910010049] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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