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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. Biochim Biophys Acta Bioenerg 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] [What about the content of this article? (0)] [Affiliation(s)] [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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Knox PP, Lukashev EP, Korvatovsky BN, Mamedov MD, Strakhovskaya MG, Gvozdev DA, Paschenko VZ, Rubin AB. The influence of cationic antiseptics on the processes of light energy conversion in various photosynthetic pigment-protein complexes. Photosynth Res 2024:10.1007/s11120-024-01082-w. [PMID: 38466457 DOI: 10.1007/s11120-024-01082-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/20/2023] [Accepted: 01/29/2024] [Indexed: 03/13/2024]
Abstract
The widespread use of disinfectants and antiseptics, and consequently their release into the environment, determines the relevance of studying their potential impact on the main producers of organic matter on the planet-photosynthetic organisms. The review examines the effects of some biguanides and quaternary ammonium compounds, octenidine, miramistin, chlorhexidine, and picloxidine, on the functioning of the photosynthetic apparatus of various organisms (Strakhovskaya et al. in Photosynth Res 147:197-209, 2021; Knox et al. in Photosynth Res 153:103, 2022; Paschenko et al. in Photosynth Res 155:93-105, 2023a, Photosynth Res 2023b). A common feature of these antiseptics is the combination of hydrophobic and hydrophilic regions in the molecules, the latter carrying a positive charge(s). The comparison of the results obtained with intact bacterial membrane vesicles (chromatophores) and purified pigment-protein complexes (photosystem II and I) of oxygenic organisms allows us to draw conclusions about the mechanisms of the cationic antiseptic action on the functional properties of the components of the photosynthetic apparatus.
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Affiliation(s)
- Peter P Knox
- Biophysical Department, Faculty of Biology, Moscow State University, Leninskye Gory 1, Build. 24, Moscow, Russia, 119234
| | - Eugene P Lukashev
- Biophysical Department, Faculty of Biology, Moscow State University, Leninskye Gory 1, Build. 24, Moscow, Russia, 119234
| | - Boris N Korvatovsky
- Biophysical Department, Faculty of Biology, Moscow State University, Leninskye Gory 1, Build. 24, Moscow, Russia, 119234
| | - Mahir D Mamedov
- A.N. Belozersky Institute of Physico-Chemical Biology, Moscow State University, Leninskye Gory 1, Build. 40, Moscow, Russia, 119992
| | - Marina G Strakhovskaya
- Synthetic Biology Department, Faculty of Biology, Moscow State University, Leninskye Gory 1, Build. 12, Moscow, Russia, 119234
| | - Daniil A Gvozdev
- Biophysical Department, Faculty of Biology, Moscow State University, Leninskye Gory 1, Build. 24, Moscow, Russia, 119234.
| | - Vladimir Z Paschenko
- Biophysical Department, Faculty of Biology, Moscow State University, Leninskye Gory 1, Build. 24, Moscow, Russia, 119234
| | - Andrew B Rubin
- Biophysical Department, Faculty of Biology, Moscow State University, Leninskye Gory 1, Build. 24, Moscow, Russia, 119234
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Paschenko VZ, Lukashev EP, Mamedov MD, Gvozdev DA, Knox PP. Effect of cationic antiseptics on fluorescent characteristics and electron transfer in cyanobacterial photosystem I complexes. Photosynth Res 2024; 159:241-251. [PMID: 37480468 DOI: 10.1007/s11120-023-01039-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/17/2023] [Accepted: 07/09/2023] [Indexed: 07/24/2023]
Abstract
In this study, the effects of cationic antiseptics such as chlorhexidine, picloxidine, miramistin, and octenidine at concentrations up to 150 µM on fluorescence spectra and its lifetimes, as well as on light-induced electron transfer in protein-pigment complexes of photosystem I (PSI) isolated from cyanobacterium Synechocystis sp. PCC 6803 have been studied. In doing so, octenidine turned out to be the most "effective" in terms of its influence on the spectral and functional characteristics of PSI complexes. It has been shown that the rate of energy migration from short-wavelength forms of light-harvesting chlorophyll to long-wavelength ones slows down upon addition of octenidine to the PSI suspension. After photo-separation of charges between the primary electron donor P700 and the terminal iron-sulfur center(s) FA/FB, the rate of forward electron transfer from (FA/FB)- to the external medium slows down while the rate of charge recombination between reduced FA/FB- and photooxidized P700+ increases. The paper considers the possible causes of the observed action of the antiseptic.
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Affiliation(s)
- Vladimir Z Paschenko
- Biophysical Department, Faculty of Biology, M.V. Lomonosov Moscow State University, Leninskye Gory 1, Build. 12, Moscow, Russia, 119234
| | - Eugene P Lukashev
- Biophysical Department, Faculty of Biology, M.V. Lomonosov Moscow State University, Leninskye Gory 1, Build. 12, Moscow, Russia, 119234
| | - Mahir D Mamedov
- A.N. Belozersky Institute of Physico-Chemical Biology, Moscow State University, Leninskye Gory 1, Build. 40, Moscow, Russia, 119992
| | - Daniil A Gvozdev
- Biophysical Department, Faculty of Biology, M.V. Lomonosov Moscow State University, Leninskye Gory 1, Build. 12, Moscow, Russia, 119234.
| | - Peter P Knox
- Biophysical Department, Faculty of Biology, M.V. Lomonosov Moscow State University, Leninskye Gory 1, Build. 12, Moscow, Russia, 119234
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Petrovskaya LE, Siletsky SA, Mamedov MD, Lukashev EP, Balashov SP, Dolgikh DA, Kirpichnikov MP. Features of the Mechanism of Proton Transport in ESR, Retinal Protein from Exiguobacterium sibiricum. Biochemistry Moscow 2023; 88:1544-1554. [PMID: 38105023 DOI: 10.1134/s0006297923100103] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/06/2023] [Revised: 07/11/2023] [Accepted: 07/11/2023] [Indexed: 12/19/2023]
Abstract
Retinal-containing light-sensitive proteins - rhodopsins - are found in many microorganisms. Interest in them is largely explained by their role in light energy storage and photoregulation in microorganisms, as well as the prospects for their use in optogenetics to control neuronal activity, including treatment of various diseases. One of the representatives of microbial rhodopsins is ESR, the retinal protein of Exiguobacterium sibiricum. What distinguishes ESR from homologous proteins is the presence of a lysine residue (Lys96) as a proton donor for the Schiff base. This feature, along with the hydrogen bond of the proton acceptor Asp85 with the His57 residue, determines functional characteristics of ESR as a proton pump. This review examines the results of ESR studies conducted using various methods, including direct electrometry. Comparison of the obtained data with the results of structural studies and with other retinal proteins allows us to draw conclusions about the mechanisms of transport of hydrogen ions in ESR and similar retinal proteins.
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Affiliation(s)
- Lada E Petrovskaya
- Shemyakin and Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Moscow, 117997, Russia.
| | - Sergei A Siletsky
- Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, Moscow, 119992, Russia
| | - Mahir D Mamedov
- Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, Moscow, 119992, Russia
| | - Eugene P Lukashev
- Faculty of Biology, Lomonosov Moscow State University, Moscow, 119234, Russia
| | - Sergei P Balashov
- Department of Physiology and Biophysics, University of California, Irvine, CA 92697
| | - Dmitry A Dolgikh
- Shemyakin and Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Moscow, 117997, Russia
- Faculty of Biology, Lomonosov Moscow State University, Moscow, 119234, Russia
| | - Mikhail P Kirpichnikov
- Shemyakin and Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Moscow, 117997, Russia
- Faculty of Biology, Lomonosov Moscow State University, Moscow, 119234, Russia
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Vitukhnovskaya LA, Zaspa AA, Mamedov MD. Generation of Electric Potential Difference by Chromatophores from Photosynthetic Bacteria in the Presence of Trehalose under Continuous Illumination. Biochemistry (Mosc) 2023; 88:1428-1437. [PMID: 38105015 DOI: 10.1134/s0006297923100024] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/27/2023] [Revised: 07/20/2023] [Accepted: 08/26/2023] [Indexed: 12/19/2023]
Abstract
Measurement of electrical potential difference (Δψ) in membrane vesicles (chromatophores) from the purple bacterium Rhodobacter sphaeroides associated with the surface of a nitrocellulose membrane filter (MF) impregnated with a phospholipid solution in decane or immersed into it in the presence of exogenous mediators and disaccharide trehalose demonstrated an increase in the amplitude and stabilization of the signal under continuous illumination. The mediators were the ascorbate/N,N,N'N'-tetramethyl-p-phenylenediamine pair and ubiquinone-0 (electron donor and acceptor, respectively). Although stabilization of photoelectric responses upon long-term continuous illumination was observed for both variants of chromatophore immobilization, only the samples immersed into the MF retained the functional activity of reaction centers (RCs) for a month when stored in the dark at room temperature, which might be due to the preservation of integrity of chromatophore proteins inside the MF pores. The stabilizing effect of the bioprotector trehalose could be related to its effect on both the RC proteins and the phospholipid bilayer membrane. The results obtained will expand current ideas on the use of semi-synthetic structures based on various intact photosynthetic systems capable of converting solar energy into its electrochemical form.
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Affiliation(s)
- Liya A Vitukhnovskaya
- Belozersky Institute of Physical-Chemical Biology, Moscow State University, Moscow, 119992, Russia
- Semenov Federal Research Center for Chemical Physics, Russian Academy of Sciences, Moscow, 119991, Russia
| | - Andrei A Zaspa
- Belozersky Institute of Physical-Chemical Biology, Moscow State University, Moscow, 119992, Russia
| | - Mahir D Mamedov
- Belozersky Institute of Physical-Chemical Biology, Moscow State University, Moscow, 119992, Russia.
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Petrovskaya LE, Lukashev EP, Mamedov MD, Kryukova EA, Balashov SP, Dolgikh DA, Rubin AB, Kirpichnikov MP, Siletsky SA. Oriented Insertion of ESR-Containing Hybrid Proteins in Proteoliposomes. Int J Mol Sci 2023; 24:ijms24087369. [PMID: 37108532 PMCID: PMC10138546 DOI: 10.3390/ijms24087369] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2023] [Revised: 04/13/2023] [Accepted: 04/15/2023] [Indexed: 04/29/2023] Open
Abstract
Microbial rhodopsins comprise a diverse family of retinal-containing membrane proteins that convert absorbed light energy to transmembrane ion transport or sensory signals. Incorporation of these proteins in proteoliposomes allows their properties to be studied in a native-like environment; however, unidirectional protein orientation in the artificial membranes is rarely observed. We aimed to obtain proteoliposomes with unidirectional orientation using a proton-pumping retinal protein from Exiguobacterium sibiricum, ESR, as a model. Three ESR hybrids with soluble protein domains (mCherry or thioredoxin at the C-terminus and Caf1M chaperone at the N-terminus) were obtained and characterized. The photocycle of the hybrid proteins incorporated in proteoliposomes demonstrated a higher pKa of the M state accumulation compared to that of the wild-type ESR. Large negative electrogenic phases and an increase in the relative amplitude of kinetic components in the microsecond time range in the kinetics of membrane potential generation of ESR-Cherry and ESR-Trx indicate a decrease in the efficiency of transmembrane proton transport. On the contrary, Caf-ESR demonstrates a native-like kinetics of membrane potential generation and the corresponding electrogenic stages. Our experiments show that the hybrid with Caf1M promotes the unidirectional orientation of ESR in proteoliposomes.
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Affiliation(s)
- Lada E Petrovskaya
- Shemyakin & Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Ul. Miklukho-Maklaya, 16/10, 117997 Moscow, Russia
| | - Evgeniy P Lukashev
- Department of Biology, Lomonosov Moscow State University, Leninskie Gory, 1, 119234 Moscow, Russia
| | - Mahir D Mamedov
- Belozersky Institute of Physical-Chemical Biology, Lomonosov Moscow State University, 119991 Moscow, Russia
| | - Elena A Kryukova
- Shemyakin & Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Ul. Miklukho-Maklaya, 16/10, 117997 Moscow, Russia
| | - Sergei P Balashov
- Department of Physiology and Biophysics, University of California, Irvine, CA 92697, USA
| | - Dmitry A Dolgikh
- Shemyakin & Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Ul. Miklukho-Maklaya, 16/10, 117997 Moscow, Russia
- Department of Biology, Lomonosov Moscow State University, Leninskie Gory, 1, 119234 Moscow, Russia
| | - Andrei B Rubin
- Department of Biology, Lomonosov Moscow State University, Leninskie Gory, 1, 119234 Moscow, Russia
| | - Mikhail P Kirpichnikov
- Shemyakin & Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Ul. Miklukho-Maklaya, 16/10, 117997 Moscow, Russia
- Department of Biology, Lomonosov Moscow State University, Leninskie Gory, 1, 119234 Moscow, Russia
| | - Sergey A Siletsky
- Belozersky Institute of Physical-Chemical Biology, Lomonosov Moscow State University, 119991 Moscow, Russia
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Vitukhnovskya LA, Zaspa AA, Semenov AY, Mamedov MD. Conversion of light into electricity in a semi-synthetic system based on photosynthetic bacterial chromatophores. Biochimica et Biophysica Acta (BBA) - Bioenergetics 2023; 1864:148975. [PMID: 37001791 DOI: 10.1016/j.bbabio.2023.148975] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/29/2022] [Revised: 02/02/2023] [Accepted: 03/25/2023] [Indexed: 03/31/2023]
Abstract
Chromatophores (Chr) from photosynthetic nonsulfur purple bacterium Rhodobacter sphaeroides immobilized onto a Millipore membrane filter (MF) and sandwiched between two semiconductor indium tin oxide (ITO) electrodes (termed ITO|Chr - MF|ITO) have been used to measure voltage (ΔV) induced by continuous illumination. The maximum ΔV was detected in the presence of ascorbate / N,N,N'N'-tetramethyl-p-phenylenediamine couple, coenzyme UQ0, disaccaride trehalose and antimycin A, an inhibitor of cytochrome bc1 complex. In doing so, the light-induced electron transfer in the reaction centers was the major source of photovoltages. The stability of the voltage signal upon prolonged irradiation (>1 h) may be due to the maintenance of a conformation that is optimal for the functioning of integral protein complexes and stabilization of lipid bilayer membranes in the presence of trehalose. Retaining ∼70 % of the original photovoltage performance on the 30th day of storage at 23 °C in the dark under air was achieved after re-injection of fresh buffer (∼40 μL) containing redox mediators into the ITO|Chr - MF|ITO system. The approach we use is easy and can be extended to other biological intact systems (cells, thylakoid membranes) capable of converting energy of light.
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Paschenko VZ, Lukashev EP, Mamedov MD, Korvatovskiy BN, Knox PP. Influence of the antiseptic octenidine on spectral characteristics and energy migration processes in photosystem II core complexes. Photosynth Res 2023; 155:93-105. [PMID: 36335236 PMCID: PMC9638271 DOI: 10.1007/s11120-022-00972-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/03/2022] [Accepted: 09/29/2022] [Indexed: 06/16/2023]
Abstract
Herein, the effect of cationic antiseptics (chlorhexidine, picloxidine, miramistin, octenidine) on the initial processes of the delivery of light energy and its efficient use by the reaction centers in intact spinach photosystem II core complexes has been investigated. The characteristic effects-an increase in the fluorescence yield of light-harvesting pigments and a slowdown in the rate of energy migration in bacterial photosynthetic chromatophores has been recently demonstrated mainly in the presence of octenidine (Strakhovskaya et al., in Photosynth Res 147:197-209, 2021; Knox et al., in Photosynth Res, https://doi.org/10.1007/s11120-022-00909-8 , 2022). In this study, we also observed that in the presence of octenidine, the fluorescence intensity of photosystem II core complexes increases by 5-10 times, and the rate of energy migration from antennae to the reaction centers decreases by 3 times. In addition, with an increase in the concentration of this antiseptic, a new effect related to a shift of the spectrum, absorption and fluorescence to the short-wavelength region has been found. Similar effects were observed when detergent Triton X-100 was added to photosystem II samples. We concluded that the antiseptic primarily affects the structure of the internal light-harvesting antenna (CP43 and CP47), through which the excitation energy is delivered to the reaction center. As a result of such an impact, the chlorophyll molecules in this structure are destabilized and their optical and functional characteristics change.
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Affiliation(s)
- Vladimir Z Paschenko
- Biophysical Department, Faculty of Biology, M.V.Lomonosov Moscow State University, Leninskye Gory 1, Build. 12, Moscow, Russia, 119234
| | - Eugene P Lukashev
- Biophysical Department, Faculty of Biology, M.V.Lomonosov Moscow State University, Leninskye Gory 1, Build. 12, Moscow, Russia, 119234
| | - Mahir D Mamedov
- A.N.Belozersky Institute of Physico-Chemical Biology, Moscow State University, Leninskye Gory 1, Build. 40, Moscow, Russia, 119992
| | - Boris N Korvatovskiy
- Biophysical Department, Faculty of Biology, M.V.Lomonosov Moscow State University, Leninskye Gory 1, Build. 12, Moscow, Russia, 119234
| | - Peter P Knox
- Biophysical Department, Faculty of Biology, M.V.Lomonosov Moscow State University, Leninskye Gory 1, Build. 12, Moscow, Russia, 119234.
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Cherepanov DA, Petrova AA, Mamedov MD, Vishnevskaya AI, Gostev FE, Shelaev IV, Aybush AV, Nadtochenko VA. Comparative Absorption Dynamics of the Singlet Excited States of Chlorophylls a and d. Biochemistry (Mosc) 2022; 87:1179-1186. [PMID: 36273886 DOI: 10.1134/s000629792210011x] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/17/2022] [Revised: 04/19/2022] [Accepted: 05/06/2022] [Indexed: 06/16/2023]
Abstract
Transient absorption dynamics of chlorophylls a and d dissolved in tetrahydrofuran was measured by the broadband femtosecond laser pump-probe spectroscopy in a spectral range from 400 to 870 nm. The absorption spectra of the excited S1 singlet states of chlorophylls a and d were recorded, and the dynamics of the of the Qy band shift of the stimulated emission (Stokes shift of fluorescence) was determined in a time range from 60 fs to 4 ps. The kinetics of the intramolecular conversion Qx→Qy (electronic transition S2→S1) was measured; the characteristic relaxation time was 54 ± 3 and 45 ± 9 fs for chlorophylls a and d, respectively.
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Affiliation(s)
- Dmitry A Cherepanov
- N. N. Semenov Federal Research Center for Chemical Physics, Russian Academy of Sciences, Moscow, 119991, Russia.
- A. N. Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, Moscow, 119992, Russia
| | - Anastasia A Petrova
- A. N. Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, Moscow, 119992, Russia
| | - Mahir D Mamedov
- A. N. Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, Moscow, 119992, Russia
| | - Anna I Vishnevskaya
- A. N. Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, Moscow, 119992, Russia
| | - Fedor E Gostev
- N. N. Semenov Federal Research Center for Chemical Physics, Russian Academy of Sciences, Moscow, 119991, Russia
| | - Ivan V Shelaev
- N. N. Semenov Federal Research Center for Chemical Physics, Russian Academy of Sciences, Moscow, 119991, Russia
- A. N. Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, Moscow, 119992, Russia
| | - Arseniy V Aybush
- N. N. Semenov Federal Research Center for Chemical Physics, Russian Academy of Sciences, Moscow, 119991, Russia
| | - Victor A Nadtochenko
- N. N. Semenov Federal Research Center for Chemical Physics, Russian Academy of Sciences, Moscow, 119991, Russia
- Faculty of Chemistry, Lomonosov Moscow State University, Moscow, 119991, Russia
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Sukhanov AA, Mamedov MD, Milanovsky GE, Salikhov KM, Semenov AY. Changes in the Electron Transfer Symmetry in the Photosystem I Reaction Centers upon Removal of Iron-Sulfur Clusters. Biochemistry (Mosc) 2022; 87:1109-1118. [PMID: 36273879 DOI: 10.1134/s0006297922100042] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/04/2022] [Revised: 08/09/2022] [Accepted: 08/16/2022] [Indexed: 06/16/2023]
Abstract
In photosynthetic reaction centers of intact photosystem I (PSI) complexes from cyanobacteria, electron transfer at room temperature occurs along two symmetrical branches of redox cofactors A and B at a ratio of ~3 : 1 in favor of branch A. Previously, this has been indirectly demonstrated using pulsed absorption spectroscopy and more directly by measuring the decay modulation frequencies of electron spin echo signals (electron spin echo envelope modulation, ESEEM), which allows to determine the distance between the separated charges of the primary electron donor P700+ and phylloquinone acceptors A1A- and A1B- in the symmetric redox cofactors branches A and B. In the present work, these distances were determined using ESEEM in PSI complexes lacking three 4Fe-4S clusters, FX, FA, and FB, and the PsaC protein subunit (the so-called P700-A1 core), in which phylloquinone molecules A1A and A1B serve as the terminal electron acceptors. It was shown that in the P700-A1 core preparations, the average distance between the centers of the P700+A1- ion-radical pair at a temperature of 150 K in an aqueous glycerol solution and in a dried trehalose matrix, as well as in a trehalose matrix at 280 K, is ~25.5 Å, which corresponds to the symmetrical electron transfer along the A and B branches of redox cofactors at a ratio of 1 : 1. Possible reasons for the change in the electron transfer symmetry in PSI upon removal of the PsaC subunit and 4Fe-4S clusters FX, FA, and FB are discussed.
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Affiliation(s)
- Andrey A Sukhanov
- Zavoisky Physical-Technical Institute, FRC Kazan Scientific Center, Russian Academy of Sciences, Kazan, 420029, Russia
| | - Mahir D Mamedov
- Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, Moscow, 119234, Russia
| | - Georgy E Milanovsky
- Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, Moscow, 119234, Russia
| | - Kev M Salikhov
- Zavoisky Physical-Technical Institute, FRC Kazan Scientific Center, Russian Academy of Sciences, Kazan, 420029, Russia
| | - Alexey Yu Semenov
- Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, Moscow, 119234, Russia.
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Petrovskaya LE, Lukashev EP, Siletsky SA, Imasheva ES, Wang JM, Mamedov MD, Kryukova EA, Dolgikh DA, Rubin AB, Kirpichnikov MP, Balashov SP, Lanyi JK. Proton transfer reactions in donor site mutants of ESR, a retinal protein from Exiguobacterium sibiricum. J Photochem Photobiol B 2022; 234:112529. [PMID: 35878544 DOI: 10.1016/j.jphotobiol.2022.112529] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/06/2022] [Revised: 07/04/2022] [Accepted: 07/14/2022] [Indexed: 06/15/2023]
Abstract
Light-driven proton transport by microbial retinal proteins such as archaeal bacteriorhodopsin involves carboxylic residues as internal proton donors to the catalytic center which is a retinal Schiff base (SB). The proton donor, Asp96 in bacteriorhodopsin, supplies a proton to the transiently deprotonated Schiff base during the photochemical cycle. Subsequent proton uptake resets the protonated state of the donor. This two step process became a distinctive signature of retinal based proton pumps. Similar steps are observed also in many natural variants of bacterial proteorhodopsins and xanthorhodopsins where glutamic acid residues serve as a proton donor. Recently, however, an exception to this rule was found. A retinal protein from Exiguobacterium sibiricum, ESR, contains a Lys residue in place of Asp or Glu, which facilitates proton transfer from the bulk to the SB. Lys96 can be functionally replaced with the more common donor residues, Asp or Glu. Proton transfer to the SB in the mutants containing these replacements (K96E and K96D/A47T) is much faster than in the proteins lacking the proton donor (K96A and similar mutants), and in the case of K96D/A47T, comparable with that in the wild type, indicating that carboxylic residues can replace Lys96 as proton donors in ESR. We show here that there are important differences in the functioning of these residues in ESR from the way Asp96 functions in bacteriorhodopsin. Reprotonation of the SB and proton uptake from the bulk occur almost simultaneously during the M to N transition (as in the wild type ESR at neutral pH), whereas in bacteriorhodopsin these two steps are well separated in time and occur during the M to N and N to O transitions, respectively.
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Affiliation(s)
- Lada E Petrovskaya
- Shemyakin & Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, ul. Miklukho-Maklaya, 16/10, Moscow 117997, Russia.
| | - Evgeniy P Lukashev
- M. V. Lomonosov Moscow State University, Department of Biology, Leninskie gory, 1, Moscow 119234, Russia
| | - Sergey A Siletsky
- Belozersky Institute of Physical-Chemical Biology, Lomonosov Moscow State University, 119991 Moscow, Russian Federation.
| | - Eleonora S Imasheva
- Department of Physiology and Biophysics, University of California, Irvine, CA 92697, USA
| | - Jennifer M Wang
- Department of Physiology and Biophysics, University of California, Irvine, CA 92697, USA
| | - Mahir D Mamedov
- Belozersky Institute of Physical-Chemical Biology, Lomonosov Moscow State University, 119991 Moscow, Russian Federation
| | - Elena A Kryukova
- Shemyakin & Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, ul. Miklukho-Maklaya, 16/10, Moscow 117997, Russia; Emanuel Institute of Biochemical Physics, Kosygina str., 4, Moscow 119334, Russia
| | - Dmitriy A Dolgikh
- Shemyakin & Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, ul. Miklukho-Maklaya, 16/10, Moscow 117997, Russia; M. V. Lomonosov Moscow State University, Department of Biology, Leninskie gory, 1, Moscow 119234, Russia; Emanuel Institute of Biochemical Physics, Kosygina str., 4, Moscow 119334, Russia
| | - Andrei B Rubin
- M. V. Lomonosov Moscow State University, Department of Biology, Leninskie gory, 1, Moscow 119234, Russia
| | - Mikhail P Kirpichnikov
- Shemyakin & Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, ul. Miklukho-Maklaya, 16/10, Moscow 117997, Russia; M. V. Lomonosov Moscow State University, Department of Biology, Leninskie gory, 1, Moscow 119234, Russia
| | - Sergei P Balashov
- Department of Physiology and Biophysics, University of California, Irvine, CA 92697, USA.
| | - Janos K Lanyi
- Department of Physiology and Biophysics, University of California, Irvine, CA 92697, USA
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12
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Cherepanov DA, Semenov AY, Mamedov MD, Aybush AV, Gostev FE, Shelaev IV, Shuvalov VA, Nadtochenko VA. Current state of the primary charge separation mechanism in photosystem I of cyanobacteria. Biophys Rev 2022; 14:805-820. [PMID: 36124265 PMCID: PMC9481807 DOI: 10.1007/s12551-022-00983-1] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2022] [Accepted: 07/10/2022] [Indexed: 11/24/2022] Open
Abstract
This review analyzes new data on the mechanism of ultrafast reactions of primary charge separation in photosystem I (PS I) of cyanobacteria obtained in the last decade by methods of femtosecond absorption spectroscopy. Cyanobacterial PS I from many species harbours 96 chlorophyll a (Chl a) molecules, including six specialized Chls denoted Chl1A/Chl1B (dimer P700, or PAPB), Chl2A/Chl2B, and Chl3A/Chl3B arranged in two branches, which participate in electron transfer reactions. The current data indicate that the primary charge separation occurs in a symmetric exciplex, where the special pair P700 is electronically coupled to the symmetrically located monomers Chl2A and Chl2B, which can be considered together as a symmetric exciplex Chl2APAPBChl2B with the mixed excited (Chl2APAPBChl2B)* and two charge-transfer states P700 +Chl2A - and P700 +Chl2B -. The redistribution of electrons between the branches in favor of the A-branch occurs after reduction of the Chl2A and Chl2B monomers. The formation of charge-transfer states and the symmetry breaking mechanisms were clarified by measuring the electrochromic Stark shift of β-carotene and the absorption dynamics of PS I complexes with the genetically altered Chl 2B or Chl 2A monomers. The review gives a brief description of the main methods for analyzing data obtained using femtosecond absorption spectroscopy. The energy levels of excited and charge-transfer intermediates arising in the cyanobacterial PS I are critically analyzed.
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Affiliation(s)
- Dmitry A. Cherepanov
- N.N. Semenov Federal Research Center for Chemical Physics, Russian Academy of Sciences, 119991, Kosygina Street 1, Moscow, Russia
| | - Alexey Yu Semenov
- N.N. Semenov Federal Research Center for Chemical Physics, Russian Academy of Sciences, 119991, Kosygina Street 1, Moscow, Russia
- A.N. Belozersky Institute of Physical-Chemical Biology, M.V. Lomonosov Moscow State University, 119992 Leninskye gory 1 building, 40 Moscow, Russia
| | - Mahir D. Mamedov
- A.N. Belozersky Institute of Physical-Chemical Biology, M.V. Lomonosov Moscow State University, 119992 Leninskye gory 1 building, 40 Moscow, Russia
| | - Arseniy V. Aybush
- N.N. Semenov Federal Research Center for Chemical Physics, Russian Academy of Sciences, 119991, Kosygina Street 1, Moscow, Russia
| | - Fedor E. Gostev
- N.N. Semenov Federal Research Center for Chemical Physics, Russian Academy of Sciences, 119991, Kosygina Street 1, Moscow, Russia
| | - Ivan V. Shelaev
- N.N. Semenov Federal Research Center for Chemical Physics, Russian Academy of Sciences, 119991, Kosygina Street 1, Moscow, Russia
| | - Vladimir A. Shuvalov
- N.N. Semenov Federal Research Center for Chemical Physics, Russian Academy of Sciences, 119991, Kosygina Street 1, Moscow, Russia
| | - Victor A. Nadtochenko
- N.N. Semenov Federal Research Center for Chemical Physics, Russian Academy of Sciences, 119991, Kosygina Street 1, Moscow, Russia
- Department of Chemistry, Lomonosov Moscow State University, 119991, Leninskiye Gory 1-3, Moscow, Russia
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Bogachev AV, Baykov AA, Bertsova YV, Mamedov MD. Mechanism of Ion Translocation by Na+-Rhodopsin. Biochemistry Moscow 2022; 87:731-741. [DOI: 10.1134/s0006297922080053] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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Mamedov MD, Milanovsky GE, Vitukhnovskaya L, Semenov AY. Measurements of the light-induced steady state electric potential generation by photosynthetic pigment-protein complexes. Biophys Rev 2022; 14:933-939. [DOI: 10.1007/s12551-022-00966-2] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2022] [Accepted: 05/26/2022] [Indexed: 12/17/2022] Open
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Vitukhnovskaya LA, Simonyan RA, Semenov AY, Mamedov MD. Generation of Photoelectric Responses by Photosystem II Core Complexes in the Presence of Externally Added Cytochrome c. Biochemistry (Mosc) 2021; 86:1369-1376. [PMID: 34906039 DOI: 10.1134/s0006297921110018] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/10/2021] [Revised: 09/20/2021] [Accepted: 09/20/2021] [Indexed: 06/14/2023]
Abstract
The effect of exogenous cytochrome c (cyt c) on kinetics of photoelectric responses (Δψ) of two types of photosystem II (PSII) core complexes (intact - PSII with active water-oxidizing complex and Mn-depleted complex) reconstituted into liposomes has been investigated by direct electrometric technique. PSII complexes were localized in the proteoliposome membranes with their donor side outward. An additional electrogenic phase was observed in the kinetics of Δψ generation in response to a laser flash besides the main fast (<0.3 µs) electrogenic component due to electron transfer from the redox-active tyrosine YZ to the primary quinone acceptor QA in the presence of oxidized cyt c (cyt c3+) entrapped in the internal space of proteoliposomes with intact PSII complexes. This component with characteristic time τ ≈ 40 µs and relative amplitude of ~10% of the total Δψ was attributed to the vectorial electron transfer from QA- to cyt c3+ serving as an external acceptor. An additional electrogenic component with τ ~ 70 µs and a relative amplitude of ~20% of the total Δψ also appeared in the kinetics of Δψ formation, when cyt c2+ was added to the suspension of proteoliposomes containing Mn-depleted PSII core complexes. This component was attributed to the electrogenic transfer of an electron from cyt c2+ to photooxidized tyrosine YZ. These data imply that cyt c3+ serves as a very effective exogenous electron acceptor for QA- in the case of intact PSII core complexes, and cyt c2+ is an extremely efficient artificial electron donor for YZ in the Mn-depleted PSII. The obtained data on the roles of cyt c2+ and cyt c3+ as an electron donor and acceptor for PSII, respectively, can be used to develop hybrid photoelectrochemical solar energy-converting systems based on photosynthetic pigment-protein complexes.
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Affiliation(s)
- Liya A Vitukhnovskaya
- Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, Moscow, 119992, Russia
- Semenov Federal Research Center for Chemical Physics, Russian Academy of Sciences, Moscow, 119991, Russia
| | - Ruben A Simonyan
- Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, Moscow, 119992, Russia
| | - Alexey Yu Semenov
- Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, Moscow, 119992, Russia
- Semenov Federal Research Center for Chemical Physics, Russian Academy of Sciences, Moscow, 119991, Russia
| | - Mahir D Mamedov
- Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, Moscow, 119992, Russia.
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Mamedov MD, Milanovsky GE, Malferrari M, Vitukhnovskaya LA, Francia F, Semenov AY, Venturoli G. Trehalose matrix effects on electron transfer in Mn-depleted protein-pigment complexes of Photosystem II. Biochim Biophys Acta Bioenerg 2021; 1862:148413. [PMID: 33716033 DOI: 10.1016/j.bbabio.2021.148413] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Received: 12/08/2020] [Revised: 02/15/2021] [Accepted: 03/07/2021] [Indexed: 11/18/2022]
Abstract
The kinetics of flash-induced re-reduction of the Photosystem II (PS II) primary electron donor P680 was studied in solution and in trehalose glassy matrices at different relative humidity. In solution, and in the re-dissolved glass, kinetics were dominated by two fast components with lifetimes in the range of 2-7 μs, which accounted for >85% of the decay. These components were ascribed to the direct electron transfer from the redox-active tyrosine YZ to P680+. The minor slower components were due to charge recombination between the primary plastoquinone acceptor QA- and P680+. Incorporation of the PS II complex into the trehalose glassy matrix and its successive dehydration caused a progressive increase in the lifetime of all kinetic phases, accompanied by an increase of the amplitudes of the slower phases at the expense of the faster phases. At 63% relative humidity the fast components contribution dropped to ~50%. A further dehydration of the trehalose glass did not change the lifetimes and contribution of the kinetic components. This effect was ascribed to the decrease of conformational mobility of the protein domain between YZ and P680, which resulted in the inhibition of YZ → P680+ electron transfer in about half of the PS II population, wherein the recombination between QA- and P680+ occurred. The data indicate that PS II binds a larger number of water molecules as compared to PS I complexes. We conclude that our data disprove the "water replacement" hypothesis of trehalose matrix biopreservation.
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Affiliation(s)
- Mahir D Mamedov
- A.N. Belozersky Institute of Physical-Chemical Biology, Lomonosov Moscow State University, 119992 Moscow, Leninskye gory, 1, b.40, Russia
| | - Georgy E Milanovsky
- A.N. Belozersky Institute of Physical-Chemical Biology, Lomonosov Moscow State University, 119992 Moscow, Leninskye gory, 1, b.40, Russia
| | - Marco Malferrari
- Laboratory of Biochemistry and Molecular Biophysics, Department of Pharmacy and Biotechnology, FaBiT, University of Bologna, Bologna, Via Irnerio, 42, Italy
| | - Liya A Vitukhnovskaya
- A.N. Belozersky Institute of Physical-Chemical Biology, Lomonosov Moscow State University, 119992 Moscow, Leninskye gory, 1, b.40, Russia; N.N. Semenov Federal Research Center for Chemical Physics, Russian Academy of Sciences, Moscow, 119991, Kosygina Street, 4, b.1, Russia
| | - Francesco Francia
- Laboratory of Biochemistry and Molecular Biophysics, Department of Pharmacy and Biotechnology, FaBiT, University of Bologna, Bologna, Via Irnerio, 42, Italy
| | - Alexey Yu Semenov
- A.N. Belozersky Institute of Physical-Chemical Biology, Lomonosov Moscow State University, 119992 Moscow, Leninskye gory, 1, b.40, Russia; N.N. Semenov Federal Research Center for Chemical Physics, Russian Academy of Sciences, Moscow, 119991, Kosygina Street, 4, b.1, Russia.
| | - Giovanni Venturoli
- Laboratory of Biochemistry and Molecular Biophysics, Department of Pharmacy and Biotechnology, FaBiT, University of Bologna, Bologna, Via Irnerio, 42, Italy; Consorzio Nazionale Interuniversitario per le Scienze Fisiche della Materia, CNISM, c/o Department of Physics and Astronomy "Augusto Righi", DIFA, University of Bologna, Bologna, Via Irnerio, 46, Italy.
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17
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Cherepanov DA, Shelaev IV, Gostev FE, Aybush AV, Mamedov MD, Shuvalov VA, Semenov AY, Nadtochenko VA. Generation of ion-radical chlorophyll states in the light-harvesting antenna and the reaction center of cyanobacterial photosystem I. Photosynth Res 2020; 146:55-73. [PMID: 32144697 DOI: 10.1007/s11120-020-00731-0] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/15/2019] [Accepted: 02/24/2020] [Indexed: 05/09/2023]
Abstract
The energy and charge-transfer processes in photosystem I (PS I) complexes isolated from cyanobacteria Thermosynechococcus elongatus and Synechocystis sp. PCC 6803 were investigated by pump-to-probe femtosecond spectroscopy. The formation of charge-transfer (CT) states in excitonically coupled chlorophyll a complexes (exciplexes) was monitored by measuring the electrochromic shift of β-carotene in the spectral range 500-510 nm. The excitation of high-energy chlorophyll in light-harvesting antenna of both species was not accompanied by immediate appearance of an electrochromic shift. In PS I from T. elongatus, the excitation of long-wavelength chlorophyll (LWC) caused a pronounced electrochromic effect at 502 nm assigned to the appearance of CT states of chlorophyll exciplexes. The formation of ion-radical pair P700+A1- at 40 ps was limited by energy transfer from LWC to the primary donor P700 and accompanied by carotenoid bleach at 498 nm. In PS I from Synechocystis 6803, the excitation at 720 nm produced an immediate bidentate bleach at 690/704 nm and synchronous carotenoid response at 508 nm. The bidentate bleach was assigned to the formation of primary ion-radical state PB+Chl2B-, where negative charge is localized predominantly at the accessory chlorophyll molecule in the branch B, Chl2B. The following decrease of carotenoid signal at ~ 5 ps was ascribed to electron transfer to the more distant molecule Chl3B. The reduction of phylloquinone in the sites A1A and A1B was accompanied by a synchronous blue-shift of the carotenoid response to 498 nm, pointing to fast redistribution of unpaired electron between two branches in favor of the state PB+A1A-.
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Affiliation(s)
- Dmitry A Cherepanov
- N.N. Semenov Federal Research Center for Chemical Physics, Russian Academy of Sciences, Moscow, Russia.
| | - Ivan V Shelaev
- N.N. Semenov Federal Research Center for Chemical Physics, Russian Academy of Sciences, Moscow, Russia
| | - Fedor E Gostev
- N.N. Semenov Federal Research Center for Chemical Physics, Russian Academy of Sciences, Moscow, Russia
| | - Arseniy V Aybush
- N.N. Semenov Federal Research Center for Chemical Physics, Russian Academy of Sciences, Moscow, Russia
| | - Mahir D Mamedov
- A.N. Belozersky Institute of Physical-Chemical Biology, Moscow State University, Kosygina st., 4, Moscow, Russia, 117991
| | - Vladimir A Shuvalov
- N.N. Semenov Federal Research Center for Chemical Physics, Russian Academy of Sciences, Moscow, Russia
- A.N. Belozersky Institute of Physical-Chemical Biology, Moscow State University, Kosygina st., 4, Moscow, Russia, 117991
- Institute of Basic Biological Problems, Pushchino Scientific Center for Biological Research, Russian Academy of Sciences, Pushchino, Moscow Region, Russia
| | - Alexey Yu Semenov
- N.N. Semenov Federal Research Center for Chemical Physics, Russian Academy of Sciences, Moscow, Russia
- A.N. Belozersky Institute of Physical-Chemical Biology, Moscow State University, Kosygina st., 4, Moscow, Russia, 117991
| | - Victor A Nadtochenko
- N.N. Semenov Federal Research Center for Chemical Physics, Russian Academy of Sciences, Moscow, Russia
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Zaspa AA, Vitukhnovskaya LA, Mamedova AM, Semenov AY, Mamedov MD. Photovoltage generation by photosystem II core complexes immobilized onto a Millipore filter on an indium tin oxide electrode. J Bioenerg Biomembr 2020; 52:495-504. [PMID: 33190172 DOI: 10.1007/s10863-020-09857-1] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2020] [Accepted: 10/28/2020] [Indexed: 10/23/2022]
Abstract
The light-induced functioning of photosynthetic pigment-protein complex of photosystem II (PSII) is linked to the vectorial translocation of charges across the membrane, which results in the formation of voltage. Direct measurement of the light-induced voltage (∆V) generated by spinach oxygen-evolving PSII core complexes adsorbed onto a Millipore membrane filter (MF) on an indium tin oxide (ITO) electrode under continuous illumination has been performed. PSII was shown to participate in electron transfer from water to the ITO electrode, resulting in ∆V generation. No photovoltage was detected in PSII deprived of the water-oxidizing complex. The maximal and stable photoelectric signal was observed in the presence of disaccharide trehalose and 2,6-dichloro-1,4-benzoquinone, acting as a redox mediator between the primary quinone acceptor QA of PSII and electrode surface. Long time preservation of the steady-state photoactivity at room temperature in a simple in design ITO|PSII-MF|ITO system may be related to the retention of water molecules attached to the PSII surface in the presence of trehalose.
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Affiliation(s)
- Andrey A Zaspa
- A.N. Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, Moscow, Russia
| | - Liya A Vitukhnovskaya
- A.N. Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, Moscow, Russia.,N.N. Semenov Federal Research Center for Chemical Physics, Russian Academy of Sciences, Moscow, Russia
| | - Aida M Mamedova
- A.N. Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, Moscow, Russia.,First Moscow State Medical University, Moscow, Russia
| | - Alexey Yu Semenov
- A.N. Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, Moscow, Russia.,N.N. Semenov Federal Research Center for Chemical Physics, Russian Academy of Sciences, Moscow, Russia
| | - Mahir D Mamedov
- A.N. Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, Moscow, Russia.
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Cherepanov DA, Brady NG, Shelaev IV, Nguyen J, Gostev FE, Mamedov MD, Nadtochenko VA, Bruce BD. PSI-SMALP, a Detergent-free Cyanobacterial Photosystem I, Reveals Faster Femtosecond Photochemistry. Biophys J 2020; 118:337-351. [PMID: 31882247 PMCID: PMC6976803 DOI: 10.1016/j.bpj.2019.11.3391] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2019] [Revised: 11/17/2019] [Accepted: 11/26/2019] [Indexed: 12/12/2022] Open
Abstract
Cyanobacterial photosystem I (PSI) functions as a light-driven cyt c6-ferredoxin/oxidoreductase located in the thylakoid membrane. In this work, the energy and charge transfer processes in PSI complexes isolated from Thermosynechococcus elongatus via conventional n-dodecyl-β-D-maltoside solubilization (DM-PSI) and a, to our knowledge, new detergent-free method using styrene-maleic acid copolymers (SMA-PSI) have been investigated by pump-to-probe femtosecond laser spectroscopy. In DM-PSI preparations excited at 740 nm, the excitation remained localized on the long-wavelength chlorophyll forms within 0.1-20 ps and revealed little or no charge separation and oxidation of the special pair, P700. The formation of ion-radical pair P700+A1- occurred with a characteristic time of 36 ps, being kinetically controlled by energy transfer from the long-wavelength chlorophyll to P700. Quite surprisingly, the detergent-free SMA-PSI complexes upon excitation by these long-wave pulses undergo an ultrafast (<100 fs) charge separation in ∼45% of particles. In the remaining complexes (∼55%), the energy transfer to P700 occurred at ∼36 ps, similar to the DM-PSI. Both isolation methods result in a trimeric form of PSI, yet the SMA-PSI complexes display a heterogenous kinetic behavior. The much faster rate of charge separation suggests the existence of an ultrafast pathway for charge separation in the SMA-PSI that may be disrupted during detergent isolation.
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Affiliation(s)
- Dmitry A Cherepanov
- N. N. Semenov Federal Research Center for Chemical Physics, Russian Academy of Sciences, Moscow, Russia
| | - Nathan G Brady
- Biochemistry and Cellular and Molecular Biology Department, University of Tennessee, Knoxville, Tennessee
| | - Ivan V Shelaev
- N. N. Semenov Federal Research Center for Chemical Physics, Russian Academy of Sciences, Moscow, Russia
| | - Jon Nguyen
- Biochemistry and Cellular and Molecular Biology Department, University of Tennessee, Knoxville, Tennessee
| | - Fedor E Gostev
- N. N. Semenov Federal Research Center for Chemical Physics, Russian Academy of Sciences, Moscow, Russia
| | - Mahir D Mamedov
- A. N. Belozersky Institute of Physical-Chemical Biology, Moscow State University, Moscow, Russia
| | - Victor A Nadtochenko
- N. N. Semenov Federal Research Center for Chemical Physics, Russian Academy of Sciences, Moscow, Russia.
| | - Barry D Bruce
- Biochemistry and Cellular and Molecular Biology Department, University of Tennessee, Knoxville, Tennessee; Energy Science & Engineering Program, The Bredesen Center, University of Tennessee, Knoxville, Tennessee.
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Bertsova YV, Mamedov MD, Bogachev AV. Na+-Translocating Ferredoxin:NAD+ Oxidoreductase Is a Component of Photosynthetic Electron Transport Chain in Green Sulfur Bacteria. Biochemistry (Mosc) 2019; 84:1403-1410. [PMID: 31760926 DOI: 10.1134/s0006297919110142] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Genomes of photoautotrophic organisms containing type I photosynthetic reaction center were searched for the rnf genes encoding Na+-translocating ferredoxin:NAD+ oxidoreductase (RNF). These genes were absent in heliobacteria, cyanobacteria, algae, and plants; however, genomes of many green sulfur bacteria (especially marine ones) were found to contain the full rnf operon. Analysis of RNA isolated from the marine green sulfur bacterium Chlorobium phaeovibrioides revealed a high level of rnf expression. It was found that the activity of Na+-dependent flavodoxin:NAD+ oxidoreductase detected in the membrane fraction of Chl. phaeovibrioides was absent in the membrane fraction of the freshwater green sulfur bacterium Chlorobaculum limnaeum, which is closely related to Chl. phaeovibrioides but whose genome lacks the rnf genes. Illumination of the membrane fraction of Chl. phaeovibrioides but not of Cba. limnaeum resulted in the light-induced NAD+ reduction. Based on the obtained data, we concluded that in some green sulfur bacteria, RNF may be involved in the NADH formation that should increase the efficiency of light energy conservation in these microorganisms and can serve as the first example of the use of Na+ energetics in photosynthetic electron transport chains.
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Affiliation(s)
- Y V Bertsova
- Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, Moscow, 119234, Russia
| | - M D Mamedov
- Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, Moscow, 119234, Russia
| | - A V Bogachev
- Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, Moscow, 119234, Russia.
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Bertsova YV, Kulik LV, Mamedov MD, Baykov AA, Bogachev AV. Flavodoxin with an air-stable flavin semiquinone in a green sulfur bacterium. Photosynth Res 2019; 142:127-136. [PMID: 31302833 DOI: 10.1007/s11120-019-00658-1] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/29/2019] [Accepted: 07/04/2019] [Indexed: 06/10/2023]
Abstract
Flavodoxins are small proteins with a non-covalently bound FMN that can accept two electrons and accordingly adopt three redox states: oxidized (quinone), one-electron reduced (semiquinone), and two-electron reduced (quinol). In iron-deficient cyanobacteria and algae, flavodoxin can substitute for ferredoxin as the electron carrier in the photosynthetic electron transport chain. Here, we demonstrate a similar function for flavodoxin from the green sulfur bacterium Chlorobium phaeovibrioides (cp-Fld). The expression of the cp-Fld gene, found in a close proximity with the genes for other proteins associated with iron transport and storage, increased in a low-iron medium. cp-Fld produced in Escherichia coli exhibited the optical, ERP, and electron-nuclear double resonance spectra that were similar to those of known flavodoxins. However, unlike all other flavodoxins, cp-Fld exhibited unprecedented stability of FMN semiquinone to oxidation by air and difference in midpoint redox potentials for the quinone-semiquinone and semiquinone-quinol couples (- 110 and - 530 mV, respectively). cp-Fld could be reduced by pyruvate:ferredoxin oxidoreductase found in the membrane-free extract of Chl. phaeovibrioides cells and photo-reduced by the photosynthetic reaction center found in membrane vesicles from these cells. The green sulfur bacterium Chl. phaeovibrioides appears thus to be a new type of the photosynthetic organisms that can use flavodoxin as an alternative electron carrier to cope with iron deficiency.
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Affiliation(s)
- Yulia V Bertsova
- Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, Moscow, Russia, 119234
| | - Leonid V Kulik
- Institute of Chemical Kinetics and Combustion, Russian Academy of Sciences, Novosibirsk, Russia, 630090
- Novosibirsk State University, Novosibirsk, Russia, 630090
| | - Mahir D Mamedov
- Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, Moscow, Russia, 119234
| | - Alexander A Baykov
- Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, Moscow, Russia, 119234
| | - Alexander V Bogachev
- Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, Moscow, Russia, 119234.
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Vitukhnovskaya LA, Fedorenko EV, Mamedov MD. Electron Transfer on the Donor Side of Manganese-Depleted Photosystem 2. Biochemistry (Mosc) 2019; 84:1057-1064. [PMID: 31693465 DOI: 10.1134/s0006297919090086] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/10/2019] [Revised: 06/05/2019] [Accepted: 06/05/2019] [Indexed: 06/10/2023]
Abstract
After removal of manganese ions responsible for light-driven water oxidation, redox-active tyrosine YZ (tyrosine 161 of the D1 subunit) still remains the dominant electron donor to the photooxidized chlorophyll P680 (P680+) in the reaction center of photosystem 2 (PS2). Here, we investigated P680+ reduction by YZ under single-turnover flashes in Mn-depleted PS2 core complexes in the presence of weak acids and NH4Cl. Analysis of changes in the light-induced absorption at 830 nm (reflecting P680 redox transitions) at pH 6.0 showed that P680+ reduction is well approximated by two kinetic components with the characteristic times (τ) of ~7 and ~31 μs and relative contributions of ~54 and ~37%, respectively. In contrast to the very small effect of sodium formate (200 mM), addition of sodium acetate and NH4Cl increased the rate of electron transfer between YZ and P680+ approx. by a factor of 5. The suggestion that direct electron transfer from YZ to P680+ has a biphasic kinetics and reflects the presence of two different populations of PS2 centers was confirmed by the data obtained using direct electrometrical technique. It was demonstrated that the submillisecond two-phase kinetics of the additional electrogenic phase in the kinetics of photoelectric response due to the electron transfer between YZ and P680+ is significantly accelerated in the presence of acetate or ammonia. These results contribute to the understanding of the mechanism of interaction between the oxidized tyrosine YZ and exogenous substances (including synthetic manganese-containing compounds) capable of photooxidation of water molecule in the manganese-depleted PS2 complexes.
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Affiliation(s)
- L A Vitukhnovskaya
- Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, Moscow, 119992, Russia
- Semenov Institute of Chemical Physics, Russian Academy of Sciences, Moscow, 119334, Russia
| | - E V Fedorenko
- Moscow Institute of Physics and Technology, Dolgoprudny, Moscow Region, 141701, Russia
| | - M D Mamedov
- Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, Moscow, 119992, Russia.
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23
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Yanykin DV, Malferrari M, Rapino S, Venturoli G, Semenov AY, Mamedov MD. Hydroxyectoine protects Mn-depleted photosystem II against photoinhibition acting as a source of electrons. Photosynth Res 2019; 141:165-179. [PMID: 30701483 DOI: 10.1007/s11120-019-00617-w] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/08/2018] [Accepted: 01/17/2019] [Indexed: 06/09/2023]
Abstract
In the present study, we have investigated the effect of hydroxyectoine (Ect-OH), a heterocyclic amino acid, on oxygen evolution in photosystem II (PS II) membrane fragments and on photoinhibition of Mn-depleted PS II (apo-WOC-PS II) preparations. The degree of photoinhibition of apo-WOC-PS II preparations was estimated by the loss of the capability of exogenous electron donor (sodium ascorbate) to restore the amplitude of light-induced changes of chlorophyll fluorescence yield (∆F). It was found that Ect-OH (i) stimulates the oxygen-evolving activity of PS II, (ii) accelerates the electron transfer from exogenous electron donors (K4[Fe(CN)6], DPC, TMPD, Fe2+, and Mn2+) to the reaction center of apo-WOC-PS II, (iii) enhances the protective effect of exogenous electron donors against donor-side photoinhibition of apo-WOC-PS II preparations. It is assumed that Ect-OH can serve as an artificial electron donor for apo-WOC-PS II, which does not directly interact with either the donor or acceptor side of the reaction center. We suggest that the protein conformation in the presence of Ect-OH, which affects the extent of hydration, becomes favorable for accepting electrons from exogenous donors. To our knowledge, this is the first study dealing with redox activity of Ect-OH towards photosynthetic pigment-protein complexes.
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Affiliation(s)
- D V Yanykin
- Institute of Basic Biological Problems, FRC PSCBR RAS, Pushchino, Moscow Region, Russia, 142290.
| | - M Malferrari
- Department of Chemistry "Giacomo Ciamician", University of Bologna, Via F. Selmi 2, 40126, Bologna, Italy
| | - S Rapino
- Department of Chemistry "Giacomo Ciamician", University of Bologna, Via F. Selmi 2, 40126, Bologna, Italy
| | - G Venturoli
- Laboratory of Biochemistry and Molecular Biophysics, Department of Pharmacy and Biotechnology, FaBiT, University of Bologna, 40126, Bologna, Italy
| | - A Yu Semenov
- Belozersky Institute of Physical-Chemical Biology, Lomonosov Moscow State University, Leninskie Gory 1-40, Moscow, Russia, 119992
| | - M D Mamedov
- Belozersky Institute of Physical-Chemical Biology, Lomonosov Moscow State University, Leninskie Gory 1-40, Moscow, Russia, 119992
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24
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Knox PP, Korvatovskiy BN, Gorokhov VV, Goryachev SN, Mamedov MD, Paschenko VZ. Comparison of tryptophan fluorescence lifetimes in cyanobacterial photosystem I frozen in the light and in the dark. Photosynth Res 2019; 139:441-448. [PMID: 30353420 DOI: 10.1007/s11120-018-0595-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/27/2018] [Accepted: 10/09/2018] [Indexed: 06/08/2023]
Abstract
The dependence on temperature of tryptophan fluorescence lifetime in trimeric photosystem I (PSI) complexes from cyanobacteria Synechocystis sp. PCC 6803 during the heating of pre-frozen to - 180 °C in the dark or in the light-activated preparations has been studied. Fluorescence lifetime in samples frozen in the light was longer than in samples frozen in the dark. For samples in 65% glycerol at λreg = 335 nm and at 20 °C, the lifetime of components were as follows: τ1 ≈ 1.2 ns, τ2 ≈ 4.9 ns, and τ3 ≈ 20 ns. The contribution of the first component was negligible. To analyze the contribution of components 2 and 3 derived from frozen-thawed samples, two temperature ranges from - 180 to - 90 °C and above - 90 °C are considered. In doing so, the contributions of these components appear antiphase course to each other. The dependence on temperature of these contributions is explained by the influence of the microconformational protein dynamics on the tryptophan fluorescence lifetime. In the present work, a comparative analysis of temperature-dependent conformational dynamics and electron transfer in cyanobacterial PSI (Schlodder et al., in Biochemistry 37:9466-9476, 1998) and Rhodobacter sphaeroides reaction center complexes (Knox et al., in J Photochem Photobiol B 180:140-148, 2018) was also carried out.
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Affiliation(s)
- Peter P Knox
- Department of Biophysics, Biological Faculty of the M.V. Lomonosov Moscow State University, Moscow, Russia, 119991
| | - Boris N Korvatovskiy
- Department of Biophysics, Biological Faculty of the M.V. Lomonosov Moscow State University, Moscow, Russia, 119991
| | - Vladimir V Gorokhov
- Department of Biophysics, Biological Faculty of the M.V. Lomonosov Moscow State University, Moscow, Russia, 119991
| | - Sergey N Goryachev
- Department of Biophysics, Biological Faculty of the M.V. Lomonosov Moscow State University, Moscow, Russia, 119991
| | - Mahir D Mamedov
- A.N. Belozersky Institute of Physical-Chemical Biology, M.V. Lomonosov Moscow State University, Moscow, Russia, 119991
| | - Vladimir Z Paschenko
- Department of Biophysics, Biological Faculty of the M.V. Lomonosov Moscow State University, Moscow, Russia, 119991.
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25
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Vitukhnovskaya LA, Zharmukhamedov SK, Najafpour MM, Allakhverdiev SI, Semenov AY, Mamedov MD. Electrogenic reactions in Mn-depleted photosystem II core particles in the presence of synthetic binuclear Mn complexes. Biochem Biophys Res Commun 2018; 503:222-227. [PMID: 29879428 DOI: 10.1016/j.bbrc.2018.06.006] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2018] [Accepted: 06/04/2018] [Indexed: 11/26/2022]
Abstract
An electrometrical technique was used to investigate electron transfer between synthetic binuclear manganese (Mn) complexes, designated M - 2 and M - 3, and the redox-active neutral tyrosine radical (YZ•) in proteoliposomes containing Mn-depleted photosystem II (PS II) core particles in response to single laser flashes. In the absence of Mn-containing compounds, the observed flash-induced membrane potential (ΔΨ) decay was mainly due to charge recombination between the reduced primary quinone acceptor QA- and the oxidized YZ•. More significant slowing down of the ΔΨ decay in the presence of lower concentrations of M - 2 and M - 3 associated with electron donation from Mn in the Mn-binding site to YZ• indicates that these synthetic compounds are more effective electron donors than MnCl2. The exponential fitting of the kinetics of additional electrogenic components of ΔΨ rise in the presence of Mn-containing compounds revealed the following relative amplitudes (A) and lifetimes (τ): for MnCl2 - A∼ 3.5, τ∼150 μs, for M - 2 - A∼5%, τ∼1.4 ms, and for M - 3 - A∼5.5%, τ∼150 μs. This suggests that the efficiency of the manganese complexes in electron donation depends on the chemical nature of ligands. The experiments with EDTA-treated samples indicated that the ligands for M - 2 and M - 3 are required for their tight binding with the PS II reaction center. The obtained results demonstrate the importance of understanding the molecular mechanism(s) of flash-induced electrogenic reduction of the tyrosine radical YZ• by synthetic Mn complexes capable of splitting water into oxygen and reducing equivalents.
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Affiliation(s)
- Liya A Vitukhnovskaya
- A.N. Belozersky Institute of Physical-Chemical Biology, Moscow State University, Leninskie Gory 1-40, Moscow, 119992, Russia
| | | | - Mahdi M Najafpour
- Department of Chemistry, Institute of Advanced Studies in Basic Sciences (LASBS), Zanjan, Iran
| | | | - Alexey Yu Semenov
- A.N. Belozersky Institute of Physical-Chemical Biology, Moscow State University, Leninskie Gory 1-40, Moscow, 119992, Russia
| | - Mahir D Mamedov
- A.N. Belozersky Institute of Physical-Chemical Biology, Moscow State University, Leninskie Gory 1-40, Moscow, 119992, Russia.
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26
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Anashkin VA, Bertsova YV, Mamedov AM, Mamedov MD, Arutyunyan AM, Baykov AA, Bogachev AV. Engineering a carotenoid-binding site in Dokdonia sp. PRO95 Na +-translocating rhodopsin by a single amino acid substitution. Photosynth Res 2018; 136:161-169. [PMID: 28983723 DOI: 10.1007/s11120-017-0453-0] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/14/2017] [Accepted: 09/29/2017] [Indexed: 06/07/2023]
Abstract
Light-driven H+, Cl- and Na+ rhodopsin pumps all use a covalently bound retinal molecule to capture light energy. Some H+-pumping rhodopsins (xanthorhodopsins; XRs) additionally contain a carotenoid antenna for light absorption. Comparison of the available primary and tertiary structures of rhodopsins pinpointed a single Thr residue (Thr216) that presumably prevents carotenoid binding to Na+-pumping rhodopsins (NaRs). We replaced this residue in Dokdonia sp. PRO95 NaR with Gly, which is found in the corresponding position in XRs, and produced a variant rhodopsin in a ketocarotenoid-synthesising Escherichia coli strain. Unlike wild-type NaR, the isolated variant protein contained the tightly bound carotenoids canthaxanthin and echinenone. These carotenoids were visible in the absorption, circular dichroism and fluorescence excitation spectra of the Thr216Gly-substituted NaR, which indicates their function as a light-harvesting antenna. The amino acid substitution and the bound carotenoids did not affect the NaR photocycle. Our findings suggest that the antenna function was recently lost during NaR evolution but can be easily restored by site-directed mutagenesis.
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Affiliation(s)
- Viktor A Anashkin
- Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, Moscow, Russia, 119234
| | - Yulia V Bertsova
- Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, Moscow, Russia, 119234
| | - Adalyat M Mamedov
- Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, Moscow, Russia, 119234
| | - Mahir D Mamedov
- Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, Moscow, Russia, 119234
| | - Alexander M Arutyunyan
- Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, Moscow, Russia, 119234
| | - Alexander A Baykov
- Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, Moscow, Russia, 119234
| | - Alexander V Bogachev
- Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, Moscow, Russia, 119234.
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27
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Semin BK, Davletshina LN, Mamedov MD. Effect of different methods of Ca 2+ extraction from PSII oxygen-evolving complex on the Q A- oxidation kinetics. Photosynth Res 2018; 136:83-91. [PMID: 28895009 DOI: 10.1007/s11120-017-0441-4] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/20/2017] [Accepted: 09/05/2017] [Indexed: 06/07/2023]
Abstract
Lumenal extrinsic proteins PsbO, PsbP, and PsbQ of photosystem II (PSII) protect the catalytic cluster Mn4CaO5 of oxygen-evolving complex (OEC) from the bulk solution and from soluble compounds in the surrounding medium. Extraction of PsbP and PsbQ proteins by NaCl-washing together with chelator EGTA is followed also by the depletion of Ca2+ cation from OEC. In this study, the effects of PsbP and PsbQ proteins, as well as Ca2+ extraction from OEC on the kinetics of the reduced primary electron acceptor (QA-) oxidation, have been studied by fluorescence decay kinetics measurements in PSII membrane fragments. We found that in addition to the impairment of OEC, removal of PsbP and PsbQ significantly slows the rate of electron transfer from QA- to the secondary quinone acceptor QB. Electron transfer from QA- to QB in photosystem II membranes with an occupied QB site was slowed down by a factor of 8. However, addition of EGTA or CaCl2 to NaCl-washed PSII did not change the kinetics of fluorescence decay. Moreover, the kinetics of QA- oxidation by QB in Ca-depleted PSII membranes obtained by treatment with citrate buffer at pH 3.0 (such treatment keeps all extrinsic proteins in PSII but extracts Ca2+ from OEC) was not changed. The results obtained indicate that the effect of NaCl-washing on the QA- to QB electron transport is due to PsbP and PsbQ extrinsic proteins extraction, but not due to Ca2+ depletion.
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Affiliation(s)
- Boris K Semin
- Department of Biophysics, Faculty of Biology, M.V. Lomonosov Moscow State University, 119234, Moscow, Russia.
| | - Lira N Davletshina
- Department of Biophysics, Faculty of Biology, M.V. Lomonosov Moscow State University, 119234, Moscow, Russia
| | - Mahir D Mamedov
- A.N. Belozersky Institute of Physico-Chemical Biology, M.V. Lomonosov Moscow State University, 119234, Moscow, Russia
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28
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Mamedov AM, Bertsova YV, Anashkin VA, Mamedov MD, Baykov AA, Bogachev AV. Identification of the key determinant of the transport promiscuity in Na +-translocating rhodopsins. Biochem Biophys Res Commun 2018; 499:600-604. [PMID: 29601812 DOI: 10.1016/j.bbrc.2018.03.196] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2018] [Accepted: 03/26/2018] [Indexed: 02/07/2023]
Abstract
Bacterial Na+-transporting rhodopsins convert solar energy into transmembrane ion potential difference. Typically, they are strictly specific for Na+, but some can additionally transport H+. To determine the structural basis of cation promiscuity in Na+-rhodopsins, we compared their primary structures and found a single position that harbors a cysteine in strictly specific Na+-rhodopsins and a serine in the promiscuous Krokinobacter eikastus Na+-rhodopsin (Kr2). A Cys253Ser variant of the strictly specific Dokdonia sp. PRO95 Na+-rhodopsin (NaR) was indeed found to transport both Na+ and H+ in a light-dependent manner when expressed in retinal-producing Escherichia coli cells. The dual specificity of the NaR variant was confirmed by analysis of its photocycle, which revealed an acceleration of the cation-capture step by comparison with the wild-type NaR in a Na+-deficient medium. The structural basis for the dependence of the Na+/H+ specificity in Na+-rhodopsin on residue 253 remains to be determined.
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Affiliation(s)
- Adalyat M Mamedov
- Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, Moscow 119234, Russia
| | - Yulia V Bertsova
- Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, Moscow 119234, Russia
| | - Viktor A Anashkin
- Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, Moscow 119234, Russia
| | - Mahir D Mamedov
- Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, Moscow 119234, Russia
| | - Alexander A Baykov
- Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, Moscow 119234, Russia
| | - Alexander V Bogachev
- Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, Moscow 119234, Russia.
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29
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Shelaev IV, Mamedov MD, Gostev FE, Aybush AV, Li M, Nguyen J, Bruce BD, Nadtochenko VA. Comparisons of Electron Transfer Reactions in a Cyanobacterial Tetrameric and Trimeric Photosystem I Complexes. Photochem Photobiol 2018; 94:564-569. [DOI: 10.1111/php.12886] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2017] [Accepted: 12/05/2017] [Indexed: 11/30/2022]
Affiliation(s)
- Ivan V. Shelaev
- N.N. Semenov Institute of Chemical Physics Russian Academy of Sciences Moscow Russia
| | - Mahir D. Mamedov
- A.N. Belozersky Institute of Physical–Chemical Biology Moscow State University Moscow Russia
| | - Fedor E. Gostev
- N.N. Semenov Institute of Chemical Physics Russian Academy of Sciences Moscow Russia
| | - Arseny V. Aybush
- N.N. Semenov Institute of Chemical Physics Russian Academy of Sciences Moscow Russia
| | - Meng Li
- Department of Biochemistry and Cellular and Molecular Biology University of Tennessee Knoxville TN
- Bredesen Center for Interdisciplinary Research University of Tennessee Knoxville TN
| | - Jonathan Nguyen
- Department of Biochemistry and Cellular and Molecular Biology University of Tennessee Knoxville TN
| | - Barry D. Bruce
- Department of Biochemistry and Cellular and Molecular Biology University of Tennessee Knoxville TN
- Bredesen Center for Interdisciplinary Research University of Tennessee Knoxville TN
- Department of Microbiology University of Tennessee Knoxville TN
| | - Victor A. Nadtochenko
- N.N. Semenov Institute of Chemical Physics Russian Academy of Sciences Moscow Russia
- Moscow Institute of Physics and Technology Dolgoprudny Russia
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Petrova AA, Boskhomdzhieva BK, Milanovsky GE, Koksharova OA, Mamedov MD, Cherepanov DA, Semenov AY. Interaction of various types of photosystem I complexes with exogenous electron acceptors. Photosynth Res 2017; 133:175-184. [PMID: 28357617 DOI: 10.1007/s11120-017-0371-1] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/21/2016] [Accepted: 03/14/2017] [Indexed: 05/19/2023]
Abstract
Interaction of photosystem I (PS I) complexes from cyanobacteria Synechocystis sp. PCC 6803 containing various quinones in the A1-site (phylloquinone PhQ in the wild-type strain (WT), and plastoquinone PQ or 2,3-dichloronaphthoquinone Cl 2 NQ in the menB deletion strain) and different numbers of Fe4S4 clusters (intact WT and FX-core complexes depleted of FA/FB centers) with external acceptors has been studied. The efficiency of interaction was estimated by measuring the light-induced absorption changes at 820 nm due to the reduction of the special pair of chlorophylls (P700+) by an external acceptor(s). It was shown that externally added Cl 2 NQ is able to effectively accept electrons from the terminal iron-sulfur clusters of PS I. Moreover, the efficiency of Cl 2 NQ as external acceptor was higher than the efficiency of the commonly used artificial electron acceptor, methylviologen (MV) for both the intact WT PS I and for the FX-core complexes. The comparison of the efficiency of MV interaction with different types of PS I complexes revealed gradual decrease in the following order: intact WT > menB > FX-core. The effect of MV on the recombination kinetics in menB complexes of PS I with Cl 2 NQ in the A1-site differed significantly from all other PS I samples. The obtained effects are considered in terms of kinetic efficiency of electron acceptors in relation to thermodynamic and structural characteristics of PS I complexes.
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Affiliation(s)
- Anastasia A Petrova
- A.N. Belozersky Institute of Physical-Chemical Biology, Moscow State University, Moscow, Russia
| | - Baina K Boskhomdzhieva
- Department of Bioengineering and Bioinformatics, Moscow State University, Moscow, Russia
| | - Georgy E Milanovsky
- A.N. Belozersky Institute of Physical-Chemical Biology, Moscow State University, Moscow, Russia
| | - Olga A Koksharova
- A.N. Belozersky Institute of Physical-Chemical Biology, Moscow State University, Moscow, Russia
| | - Mahir D Mamedov
- A.N. Belozersky Institute of Physical-Chemical Biology, Moscow State University, Moscow, Russia
| | - Dmitry A Cherepanov
- A.N. Belozersky Institute of Physical-Chemical Biology, Moscow State University, Moscow, Russia
- A.N. Frumkin Institute of Physical Chemistry and Electrochemistry, Russian Academy of Sciences, Moscow, Russia
| | - Alexey Yu Semenov
- A.N. Belozersky Institute of Physical-Chemical Biology, Moscow State University, Moscow, Russia.
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31
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Paschenko VZ, Gorokhov VV, Grishanova NP, Korvatovskii BN, Ivanov MV, Maksimov EG, Mamedov MD. Non-photochemical Fluorescence Quenching in Photosystem II Antenna Complexes by the Reaction Center Cation Radical. Biochemistry (Mosc) 2017; 81:583-90. [PMID: 27301286 DOI: 10.1134/s0006297916060043] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
In direct experiments, rate constants of photochemical (kP) and non-photochemical (kP(+)) fluorescence quenching were determined in membrane fragments of photosystem II (PSII), in oxygen-evolving PSII core particles, as well as in core particles deprived of the oxygen-evolving complex. For this purpose, a new approach to the pulse fluorometry method was implemented. In the "dark" reaction center (RC) state, antenna fluorescence decay kinetics were measured under low-intensity excitation (532 nm, pulse repetition rate 1 Hz), and the emission was registered by a streak camera. To create a "closed" [P680(+)QA(-)] RC state, a high-intensity pre-excitation pulse (pump pulse, 532 nm) of the sample was used. The time advance of the pump pulse against the measuring pulse was 8 ns. In this experimental configuration, under the pump pulse, the [P680(+)QA(-)] state was formed in RC, whereupon antenna fluorescence kinetics was measured using a weak testing picosecond pulsed excitation light applied to the sample 8 ns after the pump pulse. The data were fitted by a two-exponential approximation. Efficiency of antenna fluorescence quenching by the photoactive RC pigment in its oxidized (P680(+)) state was found to be ~1.5 times higher than that of the neutral (P680) RC state. To verify the data obtained with a streak camera, control measurements of PSII complex fluorescence decay kinetics by the single-photon counting technique were carried out. The results support the conclusions drawn from the measurements registered with the streak camera. In this case, the fitting of fluorescence kinetics was performed in three-exponential approximation, using the value of τ1 obtained by analyzing data registered by the streak camera. An additional third component obtained by modeling the data of single photon counting describes the P680(+)Pheo(-) charge recombination. Thus, for the first time the ratio of kP(+)/kP = 1.5 was determined in a direct experiment. The mechanisms of higher efficiency for non-photochemical antenna fluorescence quenching by RC cation radical in comparison to that of photochemical quenching are discussed.
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Affiliation(s)
- V Z Paschenko
- Lomonosov Moscow State University, Faculty of Biology, Moscow, 119991, Russia.
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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. Photosynth Res 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] [What about the content of this article? (0)] [Affiliation(s)] [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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Yanykin DV, Khorobrykh AA, Mamedov MD, Klimov VV. Trehalose protects Mn-depleted photosystem 2 preparations against the donor-side photoinhibition. J Photochem Photobiol B 2016; 164:236-243. [PMID: 27693844 DOI: 10.1016/j.jphotobiol.2016.09.027] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/20/2016] [Revised: 09/15/2016] [Accepted: 09/21/2016] [Indexed: 11/30/2022]
Abstract
Recently, it has been shown that the addition of 1M trehalose leads to the increase of the rate of oxygen photoconsumption associated with activation of electron transport in the reaction center of photosystem 2 (PS2) in Mn-depleted PS2 membranes (apo-WOC-PS2) [37]. In the present work the effect of trehalose on photoinhibition of apo-WOC-PS2 preparations (which are characterized by a high sensitivity to the donor side photoinhibition of PS2) was investigated. The degree of photoinhibition was estimated by the loss of the capability of exogenous electron donor (sodium ascorbate) to reactivate the electron transport (measured by light-induced changes of chlorophyll fluorescence yield (∆F)) in apo-WOC-PS2. It was found that 1M trehalose enhanced the Mn2+-dependent suppression of photoinhibition of apo-WOC-PS2: in the presence of trehalose the addition of 0.2μM Mn2+ (corresponding to 2 Mn2+ per one reaction center) was sufficient for an almost complete suppression of the donor side photoinhibition of the complex. In the absence of trehalose it was necessary to add 100μM Mn2+ to achieve a similar result. The effect of trehalose was observed during photoinhibition of apo-WOC-PS2 at low (15μmolphotons-1m-2) and high (200μmolphotons-1m-2) light intensity. When Mn2+ was replaced by other PS2 electron donors (ferrocyanide, DPC) as well as by Ca2+ the protective effect of trehalose was not observed. It was also found that 1M trehalose decreased photoinhibition of apo-WOC-PS2 if the samples contained endogenous manganese (1-2 Mn ions per one RC was enough for the maximum protection effect). It is concluded that structural changes in PS2 caused by the addition of trehalose enhance the capability of photochemical reaction centers of apo-WOC-PS2 to accept electrons from manganese (both exogenous and endogenous), which in turn leads to a considerable suppression of the donor side photoinhibition of PS2.
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Affiliation(s)
- D V Yanykin
- Institute of Basic Biological Problems, Russian Academy of Sciences, Pushchino 142290, Moscow Region, Russia.
| | - A A Khorobrykh
- Institute of Basic Biological Problems, Russian Academy of Sciences, Pushchino 142290, Moscow Region, Russia
| | - M D Mamedov
- Lomonosov Moscow State University, Belozersky Institute of Physical-Chemical Biology, Moscow 119991, Russia
| | - V V Klimov
- Institute of Basic Biological Problems, Russian Academy of Sciences, Pushchino 142290, Moscow Region, Russia
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Malferrari M, Savitsky A, Mamedov MD, Milanovsky GE, Lubitz W, Möbius K, Semenov AY, Venturoli G. Trehalose matrix effects on charge-recombination kinetics in Photosystem I of oxygenic photosynthesis at different dehydration levels. Biochimica et Biophysica Acta (BBA) - Bioenergetics 2016; 1857:1440-1454. [DOI: 10.1016/j.bbabio.2016.05.001] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/18/2015] [Revised: 05/03/2016] [Accepted: 05/06/2016] [Indexed: 10/21/2022]
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Mamedov MD, Mamedov AM, Bertsova YV, Bogachev AV. A single mutation converts bacterial Na(+) -transporting rhodopsin into an H(+) transporter. FEBS Lett 2016; 590:2827-35. [PMID: 27447358 DOI: 10.1002/1873-3468.12324] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2016] [Revised: 07/10/2016] [Accepted: 07/13/2016] [Indexed: 11/10/2022]
Abstract
Na(+) -rhodopsins are light-driven pumps used by marine bacteria to extrude Na(+) ions from the cytoplasm. We show here that replacement of Gln123 on the cytoplasmic side of the ion-conductance channel with aspartate or glutamate confers H(+) transport activity to the Na(+) -rhodopsin from Dokdonia sp. PRO95. The Q123E variant could transport H(+) out of Escherichia coli cells in a medium containing 100 mm Na(+) and SCN(-) as the penetrating anion. The rates of the photocycle steps of this variant were only marginally dependent on Na(+) , and the major electrogenic steps were the decays of the K and O intermediates.
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Affiliation(s)
- Mahir D Mamedov
- Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, Russia
| | - Adalyat M Mamedov
- Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, Russia
| | - Yulia V Bertsova
- Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, Russia
| | - Alexander V Bogachev
- Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, 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 (Mosc) 2014; 79:197-204. [PMID: 24821445 DOI: 10.1134/s0006297914030043] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [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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Trubitsin BV, Mamedov MD, Semenov AY, Tikhonov AN. Interaction of ascorbate with photosystem I. Photosynth Res 2014; 122:215-231. [PMID: 24965848 DOI: 10.1007/s11120-014-0023-7] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/18/2013] [Accepted: 05/28/2014] [Indexed: 06/03/2023]
Abstract
Ascorbate is one of the key participants of the antioxidant defense in plants. In this work, we have investigated the interaction of ascorbate with the chloroplast electron transport chain and isolated photosystem I (PSI), using the EPR method for monitoring the oxidized centers [Formula: see text] and ascorbate free radicals. Inhibitor analysis of the light-induced redox transients of P700 in spinach thylakoids has demonstrated that ascorbate efficiently donates electrons to [Formula: see text] via plastocyanin. Inhibitors (DCMU and stigmatellin), which block electron transport between photosystem II and Pc, did not disturb the ascorbate capacity for electron donation to [Formula: see text]. Otherwise, inactivation of Pc with CN(-) ions inhibited electron flow from ascorbate to [Formula: see text]. This proves that the main route of electron flow from ascorbate to [Formula: see text] runs through Pc, bypassing the plastoquinone (PQ) pool and the cytochrome b 6 f complex. In contrast to Pc-mediated pathway, direct donation of electrons from ascorbate to [Formula: see text] is a rather slow process. Oxidized ascorbate species act as alternative oxidants for PSI, which intercept electrons directly from the terminal electron acceptors of PSI, thereby stimulating photooxidation of P700. We investigated the interaction of ascorbate with PSI complexes isolated from the wild type cells and the MenB deletion strain of cyanobacterium Synechocystis sp. PCC 6803. In the MenB mutant, PSI contains PQ in the quinone-binding A1-site, which can be substituted by high-potential electron carrier 2,3-dichloro-1,4-naphthoquinone (Cl2NQ). In PSI from the MenB mutant with Cl2NQ in the A1-site, the outflow of electrons from PSI is impeded due to the uphill electron transfer from A1 to the iron-sulfur cluster FX and further to the terminal clusters FA/FB, which manifests itself as a decrease in a steady-state level of [Formula: see text]. The addition of ascorbate promoted photooxidation of P700 due to stimulation of electron outflow from PSI to oxidized ascorbate species. Thus, accepting electrons from PSI and donating them to [Formula: see text], ascorbate can mediate cyclic electron transport around PSI. The physiological significance of ascorbate-mediated electron transport is discussed.
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Affiliation(s)
- Boris V Trubitsin
- Faculty of Physics, M.V. Lomonosov Moscow State University, Moscow, Russia
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Kozuleva MA, Petrova AA, Mamedov MD, Semenov AY, Ivanov BN. O2 reduction by photosystem I involves phylloquinone under steady-state illumination. FEBS Lett 2014; 588:4364-8. [PMID: 25311539 DOI: 10.1016/j.febslet.2014.10.003] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2014] [Revised: 09/13/2014] [Accepted: 10/01/2014] [Indexed: 11/29/2022]
Abstract
O2 reduction was investigated in photosystem I (PSI) complexes isolated from cyanobacteria Synechocystis sp. PCC 6803 wild type (WT) and menB mutant strain, which is unable to synthesize phylloquinone and contains plastoquinone at the quinone-binding site A1. PSI complexes from WT and menB mutant exhibited different dependencies of O2 reduction on light intensity, namely, the values of O2 reduction rate in WT did not reach saturation at high intensities, in contrast to the values in menB mutant. The obtained results suggest the immediate phylloquinone involvement in the light-induced O2 reduction by PSI.
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Affiliation(s)
- Marina A Kozuleva
- Institute of Basic Biological Problems, Russian Academy of Sciences, Pushchino, Russia.
| | - Anastasia A Petrova
- A.N. Belozersky Institute of Physical-Chemical Biology, Lomonosov Moscow State University, Moscow, Russia
| | - Mahir D Mamedov
- Institute of Basic Biological Problems, Russian Academy of Sciences, Pushchino, Russia; A.N. Belozersky Institute of Physical-Chemical Biology, Lomonosov Moscow State University, Moscow, Russia
| | - Alexey Yu Semenov
- A.N. Belozersky Institute of Physical-Chemical Biology, Lomonosov Moscow State University, Moscow, Russia
| | - Boris N Ivanov
- Institute of Basic Biological Problems, Russian Academy of Sciences, Pushchino, Russia
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Petrova IO, Kurashov VN, Zaspa AA, Semenov AY, Mamedov MD. Vectorial charge transfer reactions on the donor side of manganese-depleted and reconstituted photosystem 2 core complexes. Biochemistry (Mosc) 2013; 78:395-402. [PMID: 23590442 DOI: 10.1134/s0006297913040081] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
The light-induced functioning of photosystem 2 (PS 2) is directly linked to the translocation of both electrons and protons across the membrane, which results in the formation of transmembrane electric potential difference (ΔΨ). Generation of ΔΨ due to S-state transitions of the water oxidation complex was demonstrated for the first time in Mn-depleted and reconstituted PS 2 core complexes incorporated into liposomes. The kinetics and relative amplitudes of the electrogenic reactions in dark-adapted samples during S1→S2, S2→S3, and S4→S0 transitions in response to the first, second and third laser flashes were comparable to those obtained in the intact PS 2 core particles. These results expand current understanding of the nature and mechanisms of electrogenic (vectorial) reactions due to a charge transfer on the donor side of PS 2.
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Affiliation(s)
- I O Petrova
- Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, Moscow, 119234, Russia
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40
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Mamedov MD, Kurashov VN, Petrova IO, Semenov AY. Transmembrane electric potential difference in the protein-pigment complex of photosystem 2. Biochemistry (Mosc) 2012; 77:947-955. [PMID: 23157254 DOI: 10.1134/s0006297912090015] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
The protein-pigment complex of photosystem 2 (PS2) localized in the thylakoid membranes of higher plants, algae, and cyanobacteria is the main source of oxygen on Earth. The light-induced functioning of PS2 is directly linked to electron and proton transfer across the membrane, which results in the formation of transmembrane electric potential difference (ΔΨ). The major contribution to ΔΨ of the PS2 reaction center is due to charge separation between the primary chlorophyll donor P(680) and the quinone acceptor Q(A), accompanied by re-reduction of P(680)(+) by the redox-active tyrosine residue Y(Z). The processes associated with the uptake and release of protons on the acceptor and donor sides of the enzyme, respectively, are also coupled with ΔΨ generation. The objective of this work was to describe the mechanisms of ΔΨ generation associated with the S-state transitions of the water-oxidizing complex in intact PS2 complex and in PS2 preparation depleted of Mn(4)Ca cluster in the presence of artificial electron donors. The findings elucidate the mechanisms of electrogenic reactions on the PS2 donor side and may be a basis for development of an effective solar energy conversion system.
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Affiliation(s)
- M D Mamedov
- Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, 119991 Moscow, Russia.
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Mula S, Savitsky A, Möbius K, Lubitz W, Golbeck JH, Mamedov MD, Semenov AY, van der Est A. Incorporation of a high potential quinone reveals that electron transfer in Photosystem I becomes highly asymmetric at low temperature. Photochem Photobiol Sci 2012; 11:946-56. [PMID: 22246442 DOI: 10.1039/c2pp05340c] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Photosystem I (PS I) has two nearly identical branches of electron-transfer co-factors. Based on point mutation studies, there is general agreement that both branches are active at ambient temperature but that the majority of electron-transfer events occur in the A-branch. At low temperature, reversible electron transfer between P(700) and A(1A) occurs in the A-branch. However, it has been postulated that irreversible electron transfer from P(700) through A(1B) to the terminal iron-sulfur clusters F(A) and F(B) occurs via the B-branch. Thus, to study the directionality of electron transfer at low temperature, electron transfer to the iron-sulfur clusters must be blocked. Because the geometries of the donor-acceptor radical pairs formed by electron transfer in the A- and B-branch differ, they have different spin-polarized EPR spectra and echo-modulation decay curves. Hence, time-resolved, multiple-frequency EPR spectroscopy, both in the direct-detection and pulse mode, can be used to probe the use of the two branches if electron transfer to the iron-sulfur clusters is blocked. Here, we use the PS I variant from the menB deletion mutant strain of Synechocyctis sp. PCC 6803, which is unable to synthesize phylloquinone, to incorporate 2,3-dichloro-1,4-naphthoquinone (Cl(2)NQ) into the A(1A) and A(1B) binding sites. The reduction midpoint potential of Cl(2)NQ is approximately 400 mV more positive than that of phylloquinone and is unable to transfer electrons to the iron-sulfur clusters. In contrast to previous studies, in which the iron-sulfur clusters were chemically reduced and/or point mutations were used to prevent electron transfer past the quinones, we find no evidence for radical-pair formation in the B-branch. The implications of this result for the directionality of electron transfer in PS I are discussed.
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Affiliation(s)
- Sam Mula
- Department of Chemistry, Brock University, St. Catharines, ON, Canada
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Semenov AY, Kurashov VN, Mamedov MD. Transmembrane charge transfer in photosynthetic reaction centers: some similarities and distinctions. J Photochem Photobiol B 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] [What about the content of this article? (0)] [Affiliation(s)] [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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Mamedov MD, Kurashov VN, Cherepanov DA, Semenov AY. Photosysem II: where does the light-induced voltage come from? Front Biosci (Landmark Ed) 2010; 15:1007-17. [PMID: 20515738 DOI: 10.2741/3658] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Photosystem II (PS II) is a biological energy transducer. The enzyme catalyses the light-driven oxidation of water and reduction of plastoquinone. The aim of this work was to review the mechanisms of electrical events in PS II. The major contribution to the total photoelectric response is due to the charge-separation between the primary chlorophyll donor P680 and quinone acceptor QA accompanied by re-reduction of P680+ by tyrosine residue YZ. The remaining part of the membrane potential is believed to be associated mainly with electron and proton transfer events due to the S-state transitions of the oxygen-evolving complex and proton uptake associated with protonation of the doubly reduced secondary quinone acceptor QB. Under certain non-physiological conditions, some other electrogenic reactions are observed, namely: proton-coupled electron transfer between QA and non-heme Fe3+ and electron transfer from the protein-water interface to the YZ radical in the presence of artificial electron donors. These data may provide a good platform for further development of artificial photosynthetic constructs and bio-inspired catalysts.
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Affiliation(s)
- Mahir D Mamedov
- A.N. Belozersky Institute of Physical-Chemical Biology, Moscow State University, 119991 Moscow, Leninskie gory, Russia.
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Mamedov MD, Kurashov VN, Petrova IO, Zaspa AA, Semenov AY. Electron transfer between exogenous electron donors and reaction center of photosystem 2. Biochemistry (Mosc) 2010; 75:579-584. [PMID: 20632936 DOI: 10.1134/s0006297910050068] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
Transfer of electrons between artificial electron donors diphenylcarbazide (DPC) and hydroxylamine (NH2OH) and reaction center of manganese-depleted photosystem 2 (PS2) complexes was studied using the direct electrometrical method. For the first time it was shown that reduction of redox-active amino acid tyrosine Y(Z)(.) by DPC is coupled with generation of transmembrane electric potential difference (DeltaPsi). The amplitude of this phase comprised ~17% of that of the DeltaPsi phase due to electron transfer between Y(Z) and the primary quinone acceptor Q(A). This phase is associated with vectorial intraprotein electron transfer between the DPC binding site on the protein-water interface and the tyrosine Y(Z)(.). The slowing of DeltaPsi decay in the presence of NH2OH indicates effective electron transfer between the artificial electron donor and reaction center of PS2. It is suggested that NH2OH is able to diffuse through channels with diameter of 2.0-3.0 A visible in PS2 structure and leading from the protein-water interface to the Mn(4)Ca cluster binding site with the concomitant electron donation to Y(Z)(.). Because the dielectrically-weighted distance between the NH2OH binding site and Y(Z)(.) is not determined, the transfer of electrons from NH2OH to Y(Z)(.) could be either electrically silent or contribute negligibly to the observed electrogenicity in comparison with hydrophobic donors.
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Affiliation(s)
- M D Mamedov
- Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, Moscow, 119991, Russia.
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Kurashov VN, Allakhverdiev SI, Zharmukhamedov SK, Nagata T, Klimov VV, Semenov AY, Mamedov MD. Electrogenic reactions on the donor side of Mn-depleted photosystem II core particles in the presence of MnCl2and synthetic trinuclear Mn-complexes. Photochem Photobiol Sci 2009; 8:162-6. [DOI: 10.1039/b813981d] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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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. Photosynth Res 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] [What about the content of this article? (0)] [Affiliation(s)] [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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Gopta OA, Tyunyatkina AA, Kurashov VN, Semenov AY, Mamedov MD. Effect of redox mediators on the flash-induced membrane potential generation in Mn-depleted photosystem II core particles. Eur Biophys J 2007; 37:1045-50. [DOI: 10.1007/s00249-007-0231-6] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/12/2007] [Revised: 10/12/2007] [Accepted: 10/28/2007] [Indexed: 11/30/2022]
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Mamedov MD, Tyunyatkina AA, Siletsky SA, Semenov AY. Voltage changes involving photosystem II quinone–iron complex turnover. Eur Biophys J 2006; 35:647-54. [PMID: 16708211 DOI: 10.1007/s00249-006-0069-3] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/24/2006] [Revised: 04/10/2006] [Accepted: 04/20/2006] [Indexed: 11/28/2022]
Abstract
An electrometrical technique was used to investigate proton-coupled electron transfer between the primary plastoquinone acceptor Q (A) (-) and the oxidized non-heme iron Fe(3+) on the acceptor side of photosystem II core particles incorporated into phospholipid vesicles. The sign of the transmembrane electric potential difference Deltapsi (negative charging of the proteoliposome interior) indicates that the iron-quinone complex faces the interior surface of the proteoliposome membrane. Preoxidation of the non-heme iron was achieved by addition of potassium ferricyanide entrapped into proteoliposomes. Besides the fast unresolvable kinetic phase (tau approximately 0.1 micro s) of Deltapsi generation related to electron transfer between the redox-active tyrosine Y(Z) and Q(A), an additional phase in the submillisecond time domain (tau approximately 0.1 ms at 23 degrees C, pH 7.0) and relative amplitude approximately 20% of the amplitude of the fast phase was observed under exposure to the first flash. This phase was absent under the second laser flash, as well as upon the first flash in the presence of DCMU, an inhibitor of electron transfer between Q(A) and the secondary quinone Q(B). The rate of the additional electrogenic phase is decreased by about one-half in the presence of D(2)O and is reduced with the temperature decrease. On the basis of the above observations we suggest that the submillisecond electrogenic reaction induced by the first flash is due to the vectorial transfer of a proton from external aqueous phase to an amino acid residue(s) in the vicinity of the non-heme iron. The possible role of the non-heme iron in cyclic electron transfer in photosystem II complex is discussed.
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Affiliation(s)
- M D Mamedov
- A N Belozersky Institute of Physico-Chemical Biology, Moscow State University, 119992, Moscow, Leninskie Gory, Russia.
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Mamedov MD, Tyunyatkina AA, Semenov AY. Electrogenic protonation of the secondary quinone acceptor Q(B) in spinach photosystem II complexes incorporated into lipid vesicles. Biochemistry (Mosc) 2006; 70:1348-53. [PMID: 16417457 DOI: 10.1007/s10541-005-0268-z] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
The generation of transmembrane electric potential difference (delta psi) in quinone acceptor complex of proteoliposomes containing core complexes of photosystem II from spinach was studied using for the measurements a direct electrometric technique. Besides the fast increase in the membrane potential associated with the electron transfer between the redox-active tyrosine 161 residue (Y(Z)) in D1 polypeptide and the primary quinone acceptor Q(A), an additional electrogenic phase with tau approximately 0.85 msec at pH 7.3 and the maximal relative amplitude of approximately 11% of the Y(Z)ox Q(A)- phase was observed after the second light flash. The sensitivity of this phase to diuron (an inhibitor of electron transfer between Q(A) and the secondary quinone acceptor Q(B)), the dependence of its amplitude on the light flash parity, and also a decrease in its rate constant with increase in pH indicated that it was due to dismutation of Q(A)- and Q(B)- with the subsequent protonation of a doubly reduced plastoquinone molecule: Q(A)- Q(B)- + 2H+ --> Q(A)Q(B)H2.
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Affiliation(s)
- M D Mamedov
- Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, Moscow, 119992, Russia.
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Sarkisov OM, Gostev FE, Shelaev IV, Novoderezhkin VI, Gopta OA, Mamedov MD, Semenov AY, Nadtochenko VA. Long-lived coherent oscillations of the femtosecond transients in cyanobacterial photosystem I. Phys Chem Chem Phys 2006; 8:5671-8. [PMID: 17149488 DOI: 10.1039/b605660a] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
The pulsed excitation of electronic levels coupled to specific nuclear modes by a 26 fs laser pulse at 706 nm creates a wavepacket in the nuclear space of photopystem I (PS I) of Synechocystis sp. strain PCC 6803 both in the ground state and in the one-exciton manifold. Fourier transform of transient decay curves shows several low frequency peaks. The most prominent Power Spectral Density (PSD) peaks are at omega = 49 cm(-1) and omega = 88 cm(-1). The peculiarity of the coherent wavepacket in the PS I of S. sp. strain PCC 6803 is the unique, long-lived 49 cm(-1) and 88 cm(-1) oscillations with decay times up to 10 ps. It was suggested that such a long-lived coherence is determined by a contribution of the ground state wavepacket. The dependence of these two PSD peaks on the probe wavelength resembles the profile of the transient absorption spectra of PS I. The pump-probe signal in the Soret region reflects the dynamics of the ground state wavepacket created by pulsed excitation of the Q(y)-band. It was shown that the multimode Brownian oscillator model allows a quantitative fit of the oscillatory patterns of the pump-probe signal to be obtained.
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Affiliation(s)
- Oleg M Sarkisov
- N N Semenov Institute of Chemical Physics, Russian Academy of Sciences, Kosigin str 4, Moscow, Russia
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