1
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Al-Romema AA, Plass F, Nizovtsev AV, Kahnt A, Tsogoeva SB. Synthesis and Photo/Radiation Chemical Characterization of a New Redox-Stable Pyridine-Triazole Ligand. Chemphyschem 2024:e202400273. [PMID: 38819992 DOI: 10.1002/cphc.202400273] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2024] [Revised: 05/20/2024] [Accepted: 05/31/2024] [Indexed: 06/02/2024]
Abstract
Photocatalysis using transition-metal complexes is widely considered the future of effective and affordable clean-air technology. In particular, redox-stable, easily accessible ligands are decisive. Here, we report a straightforward and facile synthesis of a new highly stable 2,6-bis(triazolyl)pyridine ligand, containing a nitrile moiety as a masked anchoring group, using copper(I)-catalyzed azide-alkyne cycloaddition (CuAAC) click reaction. The reported structure mimics the binding motif of uneasy to synthesize ligands. Pulse radiolysis under oxidizing and reducing conditions provided evidence for the high stability of the formed radical cation and radical anion 2,6-di(1,2,3-triazol-1-yl)-pyridine compound, thus indicating the feasibility of utilizing this as a ligand for redox active metal complexes and the sensitization of metal-oxide semiconductors (e. g., TiO2 nanoparticles or nanotubes).
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Affiliation(s)
- Abdulaziz A Al-Romema
- Department of Chemistry and Pharmacy, Chair for Organic Chemistry I, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Nikolas-Fiebiger-Strasse 10, 91058, Erlangen, Germany
| | - Fabian Plass
- Leibniz Institute of Surface Engineering (IOM), Permoserstrasse 15, D-04318, Leipzig, Germany
- Department of Chemistry and Pharmacy, Chair for Physical Chemistry I, Egerlandstraße 3, 91058, Erlangen, Germany
| | - Alexey V Nizovtsev
- Department of Chemistry and Pharmacy, Chair for Organic Chemistry I, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Nikolas-Fiebiger-Strasse 10, 91058, Erlangen, Germany
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, 16/10, Miklukho-Maklaya, 117997, Moscow, Russian Federation
| | - Axel Kahnt
- Leibniz Institute of Surface Engineering (IOM), Permoserstrasse 15, D-04318, Leipzig, Germany
- Department of Chemistry and Pharmacy, Chair for Physical Chemistry I, Egerlandstraße 3, 91058, Erlangen, Germany
| | - Svetlana B Tsogoeva
- Department of Chemistry and Pharmacy, Chair for Organic Chemistry I, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Nikolas-Fiebiger-Strasse 10, 91058, Erlangen, Germany
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2
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Drosou M, Pantazis DA. Comprehensive Evaluation of Models for Ammonia Binding to the Oxygen Evolving Complex of Photosystem II. J Phys Chem B 2024; 128:1333-1349. [PMID: 38299511 PMCID: PMC10875651 DOI: 10.1021/acs.jpcb.3c06304] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2023] [Revised: 01/08/2024] [Accepted: 01/17/2024] [Indexed: 02/02/2024]
Abstract
The identity and insertion pathway of the substrate oxygen atoms that are coupled to dioxygen by the oxygen-evolving complex (OEC) remains a central question toward understanding Nature's water oxidation mechanism. In several studies, ammonia has been used as a small "water analogue" to elucidate the pathway of substrate access to the OEC and to aid in determining which of the oxygen ligands of the tetramanganese cluster are substrates for O-O bond formation. On the basis of structural and spectroscopic investigations, five first-sphere binding modes of ammonia have been suggested, involving either substitution of an existing H2O/OH-/O2- group or addition as an extra ligand to a metal ion of the Mn4CaO5 cluster. Some of these modes, specifically the ones involving substitution, have already been subject to spectroscopy-oriented quantum chemical investigations, whereas more recent suggestions that postulate the addition of ammonia have not been examined so far with quantum chemistry for their agreement with spectroscopic data. Herein, we use a common structural framework and theoretical methodology to evaluate structural models of the OEC that represent all proposed modes of first-sphere ammonia interaction with the OEC in its S2 state. Criteria include energetic, magnetic, kinetic, and spectroscopic properties compared against available experimental EPR, ENDOR, ESEEM, and EDNMR data. Our results show that models featuring ammonia replacing one of the two terminal water ligands on Mn4 align best with experimental data, while they definitively exclude substitution of a bridging μ-oxo ligand as well as incorporation of ammonia as a sixth ligand on Mn1 or Mn4.
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Affiliation(s)
- Maria Drosou
- Max-Planck-Institut
für Kohlenforschung, Kaiser-Wilhelm-Platz 1, Mülheim an der Ruhr 45470, Germany
- Inorganic
Chemistry Laboratory, National and Kapodistrian
University of Athens, Panepistimiopolis, Zografou 15771, Greece
| | - Dimitrios A. Pantazis
- Max-Planck-Institut
für Kohlenforschung, Kaiser-Wilhelm-Platz 1, Mülheim an der Ruhr 45470, Germany
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3
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Bigness A, Vaddypally S, Zdilla MJ, Mendoza-Cortes JL. Ubiquity of cubanes in bioinorganic relevant compounds. Coord Chem Rev 2022. [DOI: 10.1016/j.ccr.2021.214168] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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4
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Yang KR, Lakshmi KV, Brudvig GW, Batista VS. Is Deprotonation of the Oxygen-Evolving Complex of Photosystem II during the S1 → S2 Transition Suppressed by Proton Quantum Delocalization? J Am Chem Soc 2021; 143:8324-8332. [DOI: 10.1021/jacs.1c00633] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Affiliation(s)
- Ke R. Yang
- Department of Chemistry, Yale University, New Haven, Connecticut 06520-8107, United States
| | - K. V. Lakshmi
- Department of Chemistry and Chemical Biology and The Baruch ’60 Center for Biochemical Solar Energy, Rensselaer Polytechnic Institute, Troy, New York 12180, United States
| | - Gary W. Brudvig
- Department of Chemistry, Yale University, New Haven, Connecticut 06520-8107, United States
| | - Victor S. Batista
- Department of Chemistry, Yale University, New Haven, Connecticut 06520-8107, United States
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5
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Mäusle SM, Abzaliyeva A, Greife P, Simon PS, Perez R, Zilliges Y, Dau H. Activation energies for two steps in the S 2→ S 3 transition of photosynthetic water oxidation from time-resolved single-frequency infrared spectroscopy. J Chem Phys 2020; 153:215101. [PMID: 33291916 DOI: 10.1063/5.0027995] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023] Open
Abstract
The mechanism of water oxidation by the Photosystem II (PSII) protein-cofactor complex is of high interest, but specifically, the crucial coupling of protonation dynamics to electron transfer (ET) and dioxygen chemistry remains insufficiently understood. We drove spinach-PSII membranes by nanosecond-laser flashes synchronously through the water-oxidation cycle and traced the PSII processes by time-resolved single-frequency infrared (IR) spectroscopy in the spectral range of symmetric carboxylate vibrations of protein side chains. After the collection of IR-transients from 100 ns to 1 s, we analyzed the proton-removal step in the S2 ⇒ S3 transition, which precedes the ET that oxidizes the Mn4CaOx-cluster. Around 1400 cm-1, pronounced changes in the IR-transients reflect this pre-ET process (∼40 µs at 20 °C) and the ET step (∼300 µs at 20 °C). For transients collected at various temperatures, unconstrained multi-exponential simulations did not provide a coherent set of time constants, but constraining the ET time constants to previously determined values solved the parameter correlation problem and resulted in an exceptionally high activation energy of 540 ± 30 meV for the pre-ET step. We assign the pre-ET step to deprotonation of a group that is re-protonated by accepting a proton from the substrate-water, which binds concurrently with the ET step. The analyzed IR-transients disfavor carboxylic-acid deprotonation in the pre-ET step. Temperature-dependent amplitudes suggest thermal equilibria that determine how strongly the proton-removal step is reflected in the IR-transients. Unexpectedly, the proton-removal step is only weakly reflected in the 1400 cm-1 transients of PSII core complexes of a thermophilic cyanobacterium (T. elongatus).
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Affiliation(s)
- Sarah M Mäusle
- Department of Physics, Freie Universität Berlin, Arnimallee 14, 14195 Berlin, Germany
| | - Aiganym Abzaliyeva
- Department of Physics, Freie Universität Berlin, Arnimallee 14, 14195 Berlin, Germany
| | - Paul Greife
- Department of Physics, Freie Universität Berlin, Arnimallee 14, 14195 Berlin, Germany
| | - Philipp S Simon
- Department of Physics, Freie Universität Berlin, Arnimallee 14, 14195 Berlin, Germany
| | - Rebeca Perez
- Department of Physics, Freie Universität Berlin, Arnimallee 14, 14195 Berlin, Germany
| | - Yvonne Zilliges
- Department of Physics, Freie Universität Berlin, Arnimallee 14, 14195 Berlin, Germany
| | - Holger Dau
- Department of Physics, Freie Universität Berlin, Arnimallee 14, 14195 Berlin, Germany
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6
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Ghosh I, Banerjee G, Reiss K, Kim CJ, Debus RJ, Batista VS, Brudvig GW. D1-S169A substitution of photosystem II reveals a novel S 2-state structure. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2020; 1861:148301. [PMID: 32860756 DOI: 10.1016/j.bbabio.2020.148301] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/18/2019] [Revised: 08/18/2020] [Accepted: 08/22/2020] [Indexed: 10/23/2022]
Abstract
In photosystem II (PSII), photosynthetic water oxidation occurs at the O2-evolving complex (OEC), a tetramanganese-calcium cluster that cycles through light-induced redox intermediates (S0-S4) to produce oxygen from two substrate water molecules. The OEC is surrounded by a hydrogen-bonded network of amino-acid residues that plays a crucial role in proton transfer and substrate water delivery. Previously, we found that D1-S169 was crucial for water oxidation and its mutation to alanine perturbed the hydrogen-bonding network. In this study, we demonstrate that the activation energy for the S2 to S1 transition of D1-S169A PSII is higher than wild-type PSII with a ~1.7-2.7× slower rate of charge recombination with QA- relative to wild-type PSII. Arrhenius analysis of the decay kinetics shows an Ea of 5.87 ± 1.15 kcal mol-1 for decay back to the S1 state, compared to 0.80 ± 0.13 kcal mol-1 for the wild-type S2 state. In addition, we find that ammonia does not affect the S2-state EPR signal, indicating that ammonia does not bind to the Mn cluster in D1-S169A PSII. Finally, a QM/MM analysis indicates that an additional water molecule binds to the Mn4 ion in place of an oxo ligand O5 in the S2 state of D1-S169A PSII. The altered S2 state of D1-S169A PSII provides insight into the S2➔S3 state transition.
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Affiliation(s)
- Ipsita Ghosh
- Department of Chemistry, Yale University, New Haven, CT 06520-8107, USA
| | - Gourab Banerjee
- Department of Chemistry, Yale University, New Haven, CT 06520-8107, USA
| | - Krystle Reiss
- Department of Chemistry, Yale University, New Haven, CT 06520-8107, USA
| | - Christopher J Kim
- Department of Biochemistry, University of California, Riverside, CA 92521, USA
| | - Richard J Debus
- Department of Biochemistry, University of California, Riverside, CA 92521, USA.
| | - Victor S Batista
- Department of Chemistry, Yale University, New Haven, CT 06520-8107, USA
| | - Gary W Brudvig
- Department of Chemistry, Yale University, New Haven, CT 06520-8107, USA.
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7
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Banerjee G, Ghosh I, Kim CJ, Debus RJ, Brudvig GW. Bicarbonate rescues damaged proton-transfer pathway in photosystem II. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2019; 1860:611-617. [DOI: 10.1016/j.bbabio.2019.06.014] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/24/2019] [Revised: 06/18/2019] [Accepted: 06/21/2019] [Indexed: 01/04/2023]
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8
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Su XF, Zhu B, Liu L, Yan LK, Su ZM. DFT characterization on the effect of redox-inactive cation Ca2+ on water oxidation by CoII-based cuboidal catalyst. COMPUT THEOR CHEM 2019. [DOI: 10.1016/j.comptc.2019.01.023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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9
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Ghosh I, Banerjee G, Kim CJ, Reiss K, Batista VS, Debus RJ, Brudvig GW. D1-S169A Substitution of Photosystem II Perturbs Water Oxidation. Biochemistry 2019; 58:1379-1387. [DOI: 10.1021/acs.biochem.8b01184] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Affiliation(s)
- Ipsita Ghosh
- Department of Chemistry, Yale University, New Haven, Connecticut 06520-8107, United States
| | - Gourab Banerjee
- Department of Chemistry, Yale University, New Haven, Connecticut 06520-8107, United States
| | - Christopher J. Kim
- Department of Biochemistry, University of California, Riverside, California 92521, United States
| | - Krystle Reiss
- Department of Chemistry, Yale University, New Haven, Connecticut 06520-8107, United States
| | - Victor S. Batista
- Department of Chemistry, Yale University, New Haven, Connecticut 06520-8107, United States
| | - Richard J. Debus
- Department of Biochemistry, University of California, Riverside, California 92521, United States
| | - Gary W. Brudvig
- Department of Chemistry, Yale University, New Haven, Connecticut 06520-8107, United States
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10
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Shamsipur M, Pashabadi A. Latest advances in PSII features and mechanism of water oxidation. Coord Chem Rev 2018. [DOI: 10.1016/j.ccr.2018.07.006] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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11
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Affiliation(s)
- Dimitrios A. Pantazis
- Max-Planck-Institut für Kohlenforschung, Kaiser-Wilhelm-Platz 1, 45470 Mülheim an der Ruhr, Germany
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12
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Effect of carbon limitation on photosynthetic electron transport in Nannochloropsis oculata. JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY B-BIOLOGY 2018; 181:31-43. [PMID: 29486460 DOI: 10.1016/j.jphotobiol.2018.02.020] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 08/20/2017] [Revised: 02/17/2018] [Accepted: 02/17/2018] [Indexed: 01/31/2023]
Abstract
This study describes the impacts of inorganic carbon limitation on the photosynthetic efficiency and operation of photosynthetic electron transport pathways in the biofuel-candidate microalga Nannochloropsis oculata. Using a combination of highly-controlled cultivation setup (photobioreactor), variable chlorophyll a fluorescence and transient spectroscopy methods (electrochromic shift (ECS) and P700 redox kinetics), we showed that net photosynthesis and effective quantum yield of Photosystem II (PSII) decreased in N. oculata under carbon limitation. This was accompanied by a transient increase in total proton motive force and energy-dependent non-photochemical quenching as well as slightly elevated respiration. On the other hand, under carbon limitation the rapid increase in proton motive force (PMF, estimated from the total ECS signal) was also accompanied by reduced conductivity of ATP synthase to protons (estimated from the rate of ECS decay in dark after actinic illumination). This indicates that the slow operation of ATP synthase results in the transient build-up of PMF, which leads to the activation of fast energy dissipation mechanisms such as energy-dependent non-photochemical quenching. N. oculata also increased content of lipids under carbon limitation, which compensated for reduced NAPDH consumption during decreased CO2 fixation. The integrated knowledge of the underlying energetic regulation of photosynthetic processes attained with a combination of biophysical methods may be used to identify photo-physiological signatures of the onset of carbon limitation in microalgal cultivation systems, as well as to potentially identify microalgal strains that can better acclimate to carbon limitation.
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13
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Marchiori DA, Oyala PH, Debus RJ, Stich TA, Britt RD. Structural Effects of Ammonia Binding to the Mn4CaO5 Cluster of Photosystem II. J Phys Chem B 2018; 122:1588-1599. [DOI: 10.1021/acs.jpcb.7b11101] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Affiliation(s)
- David A. Marchiori
- Department
of Chemistry, University of California, Davis, Davis, California 95616, United States
| | - Paul H. Oyala
- Department
of Chemistry, University of California, Davis, Davis, California 95616, United States
- Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, California 91125, United States
| | - Richard J. Debus
- Department
of Biochemistry, University of California, Riverside, Riverside, California 92521, United States
| | - Troy A. Stich
- Department
of Chemistry, University of California, Davis, Davis, California 95616, United States
| | - R. David Britt
- Department
of Chemistry, University of California, Davis, Davis, California 95616, United States
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14
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Banerjee G, Ghosh I, Kim CJ, Debus RJ, Brudvig GW. Substitution of the D1-Asn 87 site in photosystem II of cyanobacteria mimics the chloride-binding characteristics of spinach photosystem II. J Biol Chem 2017; 293:2487-2497. [PMID: 29263091 DOI: 10.1074/jbc.m117.813170] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2017] [Revised: 12/19/2017] [Indexed: 11/06/2022] Open
Abstract
Photoinduced water oxidation at the O2-evolving complex (OEC) of photosystem II (PSII) is a complex process involving a tetramanganese-calcium cluster that is surrounded by a hydrogen-bonded network of water molecules, chloride ions, and amino acid residues. Although the structure of the OEC has remained conserved over eons of evolution, significant differences in the chloride-binding characteristics exist between cyanobacteria and higher plants. An analysis of amino acid residues in and around the OEC has identified residue 87 in the D1 subunit as the only significant difference between PSII in cyanobacteria and higher plants. We substituted the D1-Asn87 residue in the cyanobacterium Synechocystis sp. PCC 6803 (wildtype) with alanine, present in higher plants, or with aspartic acid. We studied PSII core complexes purified from D1-N87A and D1-N87D variant strains to probe the function of the D1-Asn87 residue in the water-oxidation mechanism. EPR spectra of the S2 state and flash-induced FTIR spectra of both D1-N87A and D1-N87D PSII core complexes exhibited characteristics similar to those of wildtype Synechocystis PSII core complexes. However, flash-induced O2-evolution studies revealed a decreased cycling efficiency of the D1-N87D variant, whereas the cycling efficiency of the D1-N87A PSII variant was similar to that of wildtype PSII. Steady-state O2-evolution activity assays revealed that substitution of the D1 residue at position 87 with alanine perturbs the chloride-binding site in the proton-exit channel. These findings provide new insight into the role of the D1-Asn87 site in the water-oxidation mechanism and explain the difference in the chloride-binding properties of cyanobacterial and higher-plant PSII.
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Affiliation(s)
- Gourab Banerjee
- From the Department of Chemistry, Yale University, New Haven, Connecticut 06520-8107 and
| | - Ipsita Ghosh
- From the Department of Chemistry, Yale University, New Haven, Connecticut 06520-8107 and
| | - Christopher J Kim
- the Department of Biochemistry, University of California, Riverside, California 92521
| | - Richard J Debus
- the Department of Biochemistry, University of California, Riverside, California 92521
| | - Gary W Brudvig
- From the Department of Chemistry, Yale University, New Haven, Connecticut 06520-8107 and
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15
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Askerka M, Brudvig GW, Batista VS. The O 2-Evolving Complex of Photosystem II: Recent Insights from Quantum Mechanics/Molecular Mechanics (QM/MM), Extended X-ray Absorption Fine Structure (EXAFS), and Femtosecond X-ray Crystallography Data. Acc Chem Res 2017; 50:41-48. [PMID: 28001034 DOI: 10.1021/acs.accounts.6b00405] [Citation(s) in RCA: 153] [Impact Index Per Article: 21.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Efficient photoelectrochemical water oxidation may open a way to produce energy from renewable solar power. In biology, generation of fuel due to water oxidation happens efficiently on an immense scale during the light reactions of photosynthesis. To oxidize water, photosynthetic organisms have evolved a highly conserved protein complex, Photosystem II. Within that complex, water oxidation happens at the CaMn4O5 inorganic catalytic cluster, the so-called oxygen-evolving complex (OEC), which cycles through storage "S" states as it accumulates oxidizing equivalents and produces molecular oxygen. In recent years, there has been significant progress in understanding the OEC as it evolves through the catalytic cycle. Studies have combined conventional and femtosecond X-ray crystallography with extended X-ray absorption fine structure (EXAFS) and quantum mechanics/molecular mechanics (QM/MM) methods and have addressed changes in protonation states of μ-oxo bridges and the coordination of substrate water through the analysis of ammonia binding as a chemical analog of water. These advances are thought to be critical to understanding the catalytic cycle since protonation states regulate the relative stability of different redox states and the geometry of the OEC. Therefore, establishing the mechanism for substrate water binding and the nature of protonation/redox state transitions in the OEC is essential for understanding the catalytic cycle of O2 evolution. The structure of the dark-stable S1 state has been a target for X-ray crystallography for the past 15 years. However, traditional X-ray crystallography has been hampered by radiation-induced reduction of the OEC. Very recently, a revolutionary X-ray free electron laser (XFEL) technique was applied to PSII to reveal atomic positions at 1.95 Å without radiation damage, which brought us closer than ever to establishing the ultimate structure of the OEC in the S1 state. However, the atom positions in this crystal structure are still not consistent with high-resolution EXAFS spectroscopy, partially due to the poorly resolved oxygen positions next to Mn centers and partial reduction due to extended dark adaptation of the sample. These inconsistencies led to the new models of the OEC with an alternative low oxidation state and raised questions on the protonation state of the cluster, especially the O5 μ-oxo bridge. This Account summarizes the most recent models of the OEC that emerged from QM/MM, EXAFS and femtosecond X-ray crystallography methods. When PSII in the S1 state is exposed to light, the S1 state is advanced to the higher oxidation states and eventually binds substrate water molecules. Identifying the substrate waters is of paramount importance for establishing the water-oxidation mechanism but is complicated by a large number of spectroscopically similar waters. Water analogues can, therefore, be helpful because they serve as spectroscopic markers that help to track the motion of the substrate waters. Due to a close structural and electronic similarity to water, ammonia has been of particular interest. We review three competing hypotheses on substrate water/ammonia binding and compile theoretical and experimental evidence to support them. Binding of ammonia as a sixth ligand to Mn4 during the S1 → S2 transition seems to satisfy most of the criteria, especially the most compelling recent EPR data on D1-D61A mutated PSII. Such a binding mode suggests delivery of water from the "narrow" channel through a "carousel" rearrangement of waters around Mn4 upon the S2 → S3 transition. An alternative hypothesis suggests water delivery through the "large" channel on the Ca side. However, both water delivery paths lead to a similar S3 structure, seemingly reaching consensus on the nature of the last detectable S-state intermediate in the Kok cycle before O2 evolution.
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Affiliation(s)
- Mikhail Askerka
- Department of Chemistry, Yale University, New Haven, Connecticut 06520-8107, United States
| | - Gary W. Brudvig
- Department of Chemistry, Yale University, New Haven, Connecticut 06520-8107, United States
| | - Victor S. Batista
- Department of Chemistry, Yale University, New Haven, Connecticut 06520-8107, United States
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16
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Vinyard DJ, Khan S, Brudvig GW. Photosynthetic water oxidation: binding and activation of substrate waters for O-O bond formation. Faraday Discuss 2016; 185:37-50. [PMID: 26447686 DOI: 10.1039/c5fd00087d] [Citation(s) in RCA: 51] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
Photosynthetic water oxidation occurs at the oxygen-evolving complex (OEC) of Photosystem II (PSII). The OEC, which contains a Mn4CaO5 inorganic cluster ligated by oxides, waters and amino-acid residues, cycles through five redox intermediates known as S(i) states (i = 0-4). The electronic and structural properties of the transient S4 intermediate that forms the O-O bond are not well understood. In order to gain insight into how water is activated for O-O bond formation in the S4 intermediate, we have performed a detailed analysis of S-state dependent substrate water binding kinetics taking into consideration data from Mn coordination complexes. This analysis supports a model in which the substrate waters are both bound as terminal ligands and react via a water-nucleophile attack mechanism.
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Affiliation(s)
- David J Vinyard
- Department of Chemistry, Yale University, New Haven, CT, United States.
| | - Sahr Khan
- Department of Chemistry, Yale University, New Haven, CT, United States.
| | - Gary W Brudvig
- Department of Chemistry, Yale University, New Haven, CT, United States.
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17
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Vinyard DJ, Askerka M, Debus RJ, Batista VS, Brudvig GW. Ammonia Binding in the Second Coordination Sphere of the Oxygen-Evolving Complex of Photosystem II. Biochemistry 2016; 55:4432-6. [DOI: 10.1021/acs.biochem.6b00543] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- David J. Vinyard
- Department
of Chemistry, Yale University, New Haven, Connecticut 06520-8107, United States
| | - Mikhail Askerka
- Department
of Chemistry, Yale University, New Haven, Connecticut 06520-8107, United States
| | - Richard J. Debus
- Department
of Biochemistry, University of California, Riverside, California 92521, United States
| | - Victor S. Batista
- Department
of Chemistry, Yale University, New Haven, Connecticut 06520-8107, United States
| | - Gary W. Brudvig
- Department
of Chemistry, Yale University, New Haven, Connecticut 06520-8107, United States
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18
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Askerka M, Wang J, Vinyard DJ, Brudvig GW, Batista VS. S3 State of the O2-Evolving Complex of Photosystem II: Insights from QM/MM, EXAFS, and Femtosecond X-ray Diffraction. Biochemistry 2016; 55:981-4. [DOI: 10.1021/acs.biochem.6b00041] [Citation(s) in RCA: 53] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Mikhail Askerka
- Department of Chemistry and ‡Department of
Molecular Biophysics and Biochemistry, Yale University, New Haven, Connecticut 06520-8107, United States
| | - Jimin Wang
- Department of Chemistry and ‡Department of
Molecular Biophysics and Biochemistry, Yale University, New Haven, Connecticut 06520-8107, United States
| | - David J. Vinyard
- Department of Chemistry and ‡Department of
Molecular Biophysics and Biochemistry, Yale University, New Haven, Connecticut 06520-8107, United States
| | - Gary W. Brudvig
- Department of Chemistry and ‡Department of
Molecular Biophysics and Biochemistry, Yale University, New Haven, Connecticut 06520-8107, United States
| | - Victor S. Batista
- Department of Chemistry and ‡Department of
Molecular Biophysics and Biochemistry, Yale University, New Haven, Connecticut 06520-8107, United States
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19
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Krewald V, Neese F, Pantazis DA. Redox potential tuning by redox-inactive cations in nature's water oxidizing catalyst and synthetic analogues. Phys Chem Chem Phys 2016; 18:10739-50. [DOI: 10.1039/c5cp07213a] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
Fundamental differences between synthetic manganese clusters and the biological water oxidizing catalyst are demonstrated in the modulation of their redox potential by redox-inactive cations.
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Affiliation(s)
- Vera Krewald
- Max Planck Institute for Chemical Energy Conversion
- 45470 Mülheim an der Ruhr
- Germany
| | - Frank Neese
- Max Planck Institute for Chemical Energy Conversion
- 45470 Mülheim an der Ruhr
- Germany
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20
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Guo Y, He LL, Zhao DX, Gong LD, Liu C, Yang ZZ. How does ammonia bind to the oxygen-evolving complex in the S2state of photosynthetic water oxidation? Theoretical support and implications for the W1 substitution mechanism. Phys Chem Chem Phys 2016; 18:31551-31565. [DOI: 10.1039/c6cp05725j] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
The mechanistic study shows that NH3substitutes W1 rather than O5 of the OEC in the S2state and leaves in the S4′ state.
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Affiliation(s)
- Yu Guo
- School of Chemistry and Chemical Engineering
- Liaoning Normal University
- Dalian 116029
- People's Republic of China
| | - Lan-Lan He
- School of Chemistry and Chemical Engineering
- Liaoning Normal University
- Dalian 116029
- People's Republic of China
| | - Dong-Xia Zhao
- School of Chemistry and Chemical Engineering
- Liaoning Normal University
- Dalian 116029
- People's Republic of China
| | - Li-Dong Gong
- School of Chemistry and Chemical Engineering
- Liaoning Normal University
- Dalian 116029
- People's Republic of China
| | - Cui Liu
- School of Chemistry and Chemical Engineering
- Liaoning Normal University
- Dalian 116029
- People's Republic of China
| | - Zhong-Zhi Yang
- School of Chemistry and Chemical Engineering
- Liaoning Normal University
- Dalian 116029
- People's Republic of China
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21
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Askerka M, Vinyard DJ, Brudvig GW, Batista VS. NH3 Binding to the S2 State of the O2-Evolving Complex of Photosystem II: Analogue to H2O Binding during the S2 → S3 Transition. Biochemistry 2015; 54:5783-6. [DOI: 10.1021/acs.biochem.5b00974] [Citation(s) in RCA: 60] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Mikhail Askerka
- Department of Chemistry, Yale University, New Haven, Connecticut 06520-8107, United States
| | - David J. Vinyard
- Department of Chemistry, Yale University, New Haven, Connecticut 06520-8107, United States
| | - Gary W. Brudvig
- Department of Chemistry, Yale University, New Haven, Connecticut 06520-8107, United States
| | - Victor S. Batista
- Department of Chemistry, Yale University, New Haven, Connecticut 06520-8107, United States
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22
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Oyala PH, Stich TA, Debus RJ, Britt RD. Ammonia Binds to the Dangler Manganese of the Photosystem II Oxygen-Evolving Complex. J Am Chem Soc 2015; 137:8829-37. [DOI: 10.1021/jacs.5b04768] [Citation(s) in RCA: 64] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Affiliation(s)
- Paul H. Oyala
- Department of Chemistry, University of California, Davis, Davis, California 95616, United States
| | - Troy A. Stich
- Department of Chemistry, University of California, Davis, Davis, California 95616, United States
| | - Richard J. Debus
- Department of Biochemistry, University of California, Riverside, Riverside, California 92521, United States
| | - R. David Britt
- Department of Chemistry, University of California, Davis, Davis, California 95616, United States
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