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Bogdanov A, Frydman V, Seal M, Rapatskiy L, Schnegg A, Zhu W, Iron M, Gronenborn AM, Goldfarb D. Extending the Range of Distances Accessible by 19F Electron-Nuclear Double Resonance in Proteins Using High-Spin Gd(III) Labels. J Am Chem Soc 2024; 146:6157-6167. [PMID: 38393979 PMCID: PMC10921402 DOI: 10.1021/jacs.3c13745] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2023] [Revised: 02/02/2024] [Accepted: 02/02/2024] [Indexed: 02/25/2024]
Abstract
Fluorine electron-nuclear double resonance (19F ENDOR) has recently emerged as a valuable tool in structural biology for distance determination between F atoms and a paramagnetic center, either intrinsic or conjugated to a biomolecule via spin labeling. Such measurements allow access to distances too short to be measured by double electron-electron resonance (DEER). To further extend the accessible distance range, we exploit the high-spin properties of Gd(III) and focus on transitions other than the central transition (|-1/2⟩ ↔ |+1/2⟩), that become more populated at high magnetic fields and low temperatures. This increases the spectral resolution up to ca. 7 times, thus raising the long-distance limit of 19F ENDOR almost 2-fold. We first demonstrate this on a model fluorine-containing Gd(III) complex with a well-resolved 19F spectrum in conventional central transition measurements and show quantitative agreement between the experimental spectra and theoretical predictions. We then validate our approach on two proteins labeled with 19F and Gd(III), in which the Gd-F distance is too long to produce a well-resolved 19F ENDOR doublet when measured at the central transition. By focusing on the |-5/2⟩ ↔ |-3/2⟩ and |-7/2⟩ ↔ |-5/2⟩ EPR transitions, a resolution enhancement of 4.5- and 7-fold was obtained, respectively. We also present data analysis strategies to handle contributions of different electron spin manifolds to the ENDOR spectrum. Our new extended 19F ENDOR approach may be applicable to Gd-F distances as large as 20 Å, widening the current ENDOR distance window.
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Affiliation(s)
- Alexey Bogdanov
- Department
of Chemical and Biological Physics, The
Weizmann Institute of Science, P.O. Box 26, Rehovot, 7610001, Israel
| | - Veronica Frydman
- Department
of Chemical Research Support, The Weizmann
Institute of Science, P.O. Box 26, Rehovot, 7610001, Israel
| | - Manas Seal
- Department
of Chemical and Biological Physics, The
Weizmann Institute of Science, P.O. Box 26, Rehovot, 7610001, Israel
| | - Leonid Rapatskiy
- Max
Planck Institute for Chemical Energy Conversion, 34-36 Stiftstraße, Mülheim an der Ruhr, 45470, Germany
| | - Alexander Schnegg
- Max
Planck Institute for Chemical Energy Conversion, 34-36 Stiftstraße, Mülheim an der Ruhr, 45470, Germany
| | - Wenkai Zhu
- Department
of Structural Biology, University of Pittsburgh, 4200 Fifth Avenue, Pittsburgh, Pennsylvania 15260, United States
| | - Mark Iron
- Department
of Chemical Research Support, The Weizmann
Institute of Science, P.O. Box 26, Rehovot, 7610001, Israel
| | - Angela M. Gronenborn
- Department
of Structural Biology, University of Pittsburgh, 4200 Fifth Avenue, Pittsburgh, Pennsylvania 15260, United States
| | - Daniella Goldfarb
- Department
of Chemical and Biological Physics, The
Weizmann Institute of Science, P.O. Box 26, Rehovot, 7610001, Israel
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Malissa H, Kavand M, Waters DP, van Schooten KJ, Burn PL, Vardeny ZV, Saam B, Lupton JM, Boehme C. Room-temperature coupling between electrical current and nuclear spins in OLEDs. Science 2014; 345:1487-90. [DOI: 10.1126/science.1255624] [Citation(s) in RCA: 78] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
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Santabarbara S, Kuprov I, Poluektov O, Casal A, Russell CA, Purton S, Evans MCW. Directionality of Electron-Transfer Reactions in Photosystem I of Prokaryotes: Universality of the Bidirectional Electron-Transfer Model. J Phys Chem B 2010; 114:15158-71. [PMID: 20977227 DOI: 10.1021/jp1044018] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Stefano Santabarbara
- Department of Biology, University College London, Gower Street, London WC1E 6BT, United Kingdom; Department of Physics, University of Strathclyde, 107 Rottenrow East, Glasgow G4 0NG, Scotland, United Kingdom; Physical and Theoretical Chemistry Laboratory, Department of Chemistry, University of Oxford, South Parks Road, Oxford OX1 3QZ, United Kingdom; Chemical Sciences and Engineering Division, Argonne National Laboratory, 9700 S. Cass Ave., Argonne, Illinois 60439, United States; and School of Biological
| | - Ilya Kuprov
- Department of Biology, University College London, Gower Street, London WC1E 6BT, United Kingdom; Department of Physics, University of Strathclyde, 107 Rottenrow East, Glasgow G4 0NG, Scotland, United Kingdom; Physical and Theoretical Chemistry Laboratory, Department of Chemistry, University of Oxford, South Parks Road, Oxford OX1 3QZ, United Kingdom; Chemical Sciences and Engineering Division, Argonne National Laboratory, 9700 S. Cass Ave., Argonne, Illinois 60439, United States; and School of Biological
| | - Oleg Poluektov
- Department of Biology, University College London, Gower Street, London WC1E 6BT, United Kingdom; Department of Physics, University of Strathclyde, 107 Rottenrow East, Glasgow G4 0NG, Scotland, United Kingdom; Physical and Theoretical Chemistry Laboratory, Department of Chemistry, University of Oxford, South Parks Road, Oxford OX1 3QZ, United Kingdom; Chemical Sciences and Engineering Division, Argonne National Laboratory, 9700 S. Cass Ave., Argonne, Illinois 60439, United States; and School of Biological
| | - Antonio Casal
- Department of Biology, University College London, Gower Street, London WC1E 6BT, United Kingdom; Department of Physics, University of Strathclyde, 107 Rottenrow East, Glasgow G4 0NG, Scotland, United Kingdom; Physical and Theoretical Chemistry Laboratory, Department of Chemistry, University of Oxford, South Parks Road, Oxford OX1 3QZ, United Kingdom; Chemical Sciences and Engineering Division, Argonne National Laboratory, 9700 S. Cass Ave., Argonne, Illinois 60439, United States; and School of Biological
| | - Charlotte A. Russell
- Department of Biology, University College London, Gower Street, London WC1E 6BT, United Kingdom; Department of Physics, University of Strathclyde, 107 Rottenrow East, Glasgow G4 0NG, Scotland, United Kingdom; Physical and Theoretical Chemistry Laboratory, Department of Chemistry, University of Oxford, South Parks Road, Oxford OX1 3QZ, United Kingdom; Chemical Sciences and Engineering Division, Argonne National Laboratory, 9700 S. Cass Ave., Argonne, Illinois 60439, United States; and School of Biological
| | - Saul Purton
- Department of Biology, University College London, Gower Street, London WC1E 6BT, United Kingdom; Department of Physics, University of Strathclyde, 107 Rottenrow East, Glasgow G4 0NG, Scotland, United Kingdom; Physical and Theoretical Chemistry Laboratory, Department of Chemistry, University of Oxford, South Parks Road, Oxford OX1 3QZ, United Kingdom; Chemical Sciences and Engineering Division, Argonne National Laboratory, 9700 S. Cass Ave., Argonne, Illinois 60439, United States; and School of Biological
| | - Michael C. W. Evans
- Department of Biology, University College London, Gower Street, London WC1E 6BT, United Kingdom; Department of Physics, University of Strathclyde, 107 Rottenrow East, Glasgow G4 0NG, Scotland, United Kingdom; Physical and Theoretical Chemistry Laboratory, Department of Chemistry, University of Oxford, South Parks Road, Oxford OX1 3QZ, United Kingdom; Chemical Sciences and Engineering Division, Argonne National Laboratory, 9700 S. Cass Ave., Argonne, Illinois 60439, United States; and School of Biological
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Kulik L, Lubitz W. Electron-nuclear double resonance. PHOTOSYNTHESIS RESEARCH 2009; 102:391-401. [PMID: 19184518 PMCID: PMC2847154 DOI: 10.1007/s11120-009-9401-y] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/04/2008] [Accepted: 12/31/2008] [Indexed: 05/22/2023]
Abstract
The application of electron-nuclear double resonance (ENDOR) spectroscopy for the investigation of photosynthetic systems is reviewed. The basic principles of continuous wave and pulse ENDOR are presented. Selected examples of the application of the ENDOR technique for studying stable and transient paramagnetic species, including cofactor radical ions, radical pairs, triplet states, and the oxygen-evolving complex in plant Photosystem II (PSII) are discussed. Limitations and perspectives of ENDOR spectroscopy are outlined.
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Affiliation(s)
- Leonid Kulik
- Institute of Chemical Kinetics and Combustion, Institutskaya 3, 630090 Novosibirsk, Russia
| | - Wolfgang Lubitz
- Max-Planck-Institut für Bioanorganische Chemie, Stiftstrasse 34-36, 45470 Mülheim an der Ruhr, Germany
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Srinivasan N, Golbeck JH. Protein–cofactor interactions in bioenergetic complexes: The role of the A1A and A1B phylloquinones in Photosystem I. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2009; 1787:1057-88. [DOI: 10.1016/j.bbabio.2009.04.010] [Citation(s) in RCA: 97] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/26/2009] [Revised: 04/14/2009] [Accepted: 04/22/2009] [Indexed: 10/20/2022]
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Niklas J, Epel B, Antonkine ML, Sinnecker S, Pandelia ME, Lubitz W. Electronic Structure of the Quinone Radical Anion A1•− of Photosystem I Investigated by Advanced Pulse EPR and ENDOR Techniques. J Phys Chem B 2009; 113:10367-79. [DOI: 10.1021/jp901890z] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Jens Niklas
- Max-Planck-Institut für Bioanorganische Chemie, Stiftstrasse 34-36, 45470 Mülheim/Ruhr, Germany, and Institut für Experimentalphysik, Freie Universität Berlin, Arnimallee 14, 14195 Berlin, Germany
| | - Boris Epel
- Max-Planck-Institut für Bioanorganische Chemie, Stiftstrasse 34-36, 45470 Mülheim/Ruhr, Germany, and Institut für Experimentalphysik, Freie Universität Berlin, Arnimallee 14, 14195 Berlin, Germany
| | - Mikhail L. Antonkine
- Max-Planck-Institut für Bioanorganische Chemie, Stiftstrasse 34-36, 45470 Mülheim/Ruhr, Germany, and Institut für Experimentalphysik, Freie Universität Berlin, Arnimallee 14, 14195 Berlin, Germany
| | - Sebastian Sinnecker
- Max-Planck-Institut für Bioanorganische Chemie, Stiftstrasse 34-36, 45470 Mülheim/Ruhr, Germany, and Institut für Experimentalphysik, Freie Universität Berlin, Arnimallee 14, 14195 Berlin, Germany
| | - Maria-Eirini Pandelia
- Max-Planck-Institut für Bioanorganische Chemie, Stiftstrasse 34-36, 45470 Mülheim/Ruhr, Germany, and Institut für Experimentalphysik, Freie Universität Berlin, Arnimallee 14, 14195 Berlin, Germany
| | - Wolfgang Lubitz
- Max-Planck-Institut für Bioanorganische Chemie, Stiftstrasse 34-36, 45470 Mülheim/Ruhr, Germany, and Institut für Experimentalphysik, Freie Universität Berlin, Arnimallee 14, 14195 Berlin, Germany
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High-Field/High-Frequency Electron Paramagnetic Resonance Involving Single- and Multiple-Transition Schemes. BIOPHYSICAL TECHNIQUES IN PHOTOSYNTHESIS 2008. [DOI: 10.1007/978-1-4020-8250-4_14] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
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8
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Poluektov OG, Utschig LM, Dubinskij AA, Thurnauer MC. Electron transfer pathways and protein response to charge separation in photosynthetic reaction centers: time-resolved high-field ENDOR of the spin-correlated radical pair P865(+)QA(-). J Am Chem Soc 2005; 127:4049-59. [PMID: 15771542 DOI: 10.1021/ja043063g] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Recently we reported the first observation of time-resolved (TR) high-frequency (HF) electron nuclear double resonance (ENDOR) of the transient charge separated state P865(+)Q(-)A in purple photosynthetic bacterial reaction centers (RC) (Poluektov, O. G., et al. J. Am. Chem. Soc. 2004, 126, 1644-1645). The high resolution and orientational selectivity of HF ENDOR allows us to directly probe protein environments by spectrally selecting specific nuclei in isotopically labeled samples. A new phenomenon associated with the spin correlated radical pair (SCRP) nature of P865(+)Q(-)A was observed. The TR-HF ENDOR spectra of protein nuclei (protons) surrounding deuterated QA(-) exhibit a derivative-like, complicated line shape, which differs considerably from the HF ENDOR spectrum of the protein nuclei surrounding thermally equilibrated QA(-). Here, a theoretical analysis of these observations is presented that shows that the positions and amplitudes of ENDOR lines contain information on hyperfine interactions (HFI) of a particular nucleus (a proton of the protein) with both correlated electron spins. Thus, spin density delocalization in the protein environment between the SCRP donor and acceptor molecules can be revealed via HF ENDOR. Novel approaches for acquiring and analyzing SCRP ENDOR that simplify interpretation of the spectra are discussed. Furthermore, we report here that the positions of the ENDOR lines of the SCRP shift with an increase in the time after laser flash, which initiates electron transfer. These shifts provide direct spectroscopic evidence of reorganization of the protein environment to accommodate the donor-acceptor charge-separated state P865(+)QA(-).
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Affiliation(s)
- Oleg G Poluektov
- Chemistry Division, Argonne National Laboratory, Argonne, Illinois 60439, USA.
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Pushkar YN, Karyagina I, Stehlik D, Brown S, van der Est A. Recruitment of a Foreign Quinone into the A1 Site of Photosystem I. J Biol Chem 2005; 280:12382-90. [PMID: 15640524 DOI: 10.1074/jbc.m412940200] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
In photosystem I (PS I), phylloquinone (PhQ) acts as a low potential electron acceptor during light-induced electron transfer (ET). The origin of the very low midpoint potential of the quinone is investigated by introducing anthraquinone (AQ) into PS I in the presence and absence of the iron-sulfur clusters. Solvent extraction and reincubation is used to obtain PS I particles containing AQ and the iron-sulfur clusters, whereas incubation of the menB rubA double mutant yields PS I with AQ in the PhQ site but no iron-sulfur clusters. Transient electron paramagnetic resonance spectroscopy is used to investigate the orientation of AQ in the binding site and the ET kinetics. The low temperature spectra suggest that the orientation of AQ in all samples is the same as that of PhQ in native PS I. In PS I containing the iron sulfur clusters, (i) the rate of forward electron transfer from the AQ*- to F(X) is found to be faster than from PhQ*- to F(X), and (ii) the spin polarization patterns provide indirect evidence that the preceding ET step from A0*- to quinone is slower than in the native system. The changes in the kinetics are in accordance with the more negative reduction midpoint potential of AQ. Moreover, a comparison of the spectra in the presence and absence of the iron-sulfur clusters suggests that the midpoint potential of AQ is more negative in the presence of F(X). The electron transfer from the AQ- to F(X) is found to be thermally activated with a lower apparent activation energy than for PhQ in native PS I. The spin polarization patterns show that the triplet character in the initial state of P700)*+AQ*- increases with temperature. This behavior is rationalized in terms of a model involving a distribution of lifetimes/redox potentials for A0 and related competition between charge recombination and forward electron transfer from the radical pair P700*+A0*-.
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Affiliation(s)
- Yulia N Pushkar
- Institut für Experimentalphysik, Freie Universität Berlin, Arnimallee 14, D-14195 Berlin, Germany
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An EPR/ENDOR study of the asymmetric hydrogen bond between the quinone electron acceptor and the protein backbone in Photosystem I. J Mol Struct 2004. [DOI: 10.1016/j.molstruc.2004.02.015] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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Van Der Est A, Valieva AI, Kandrashkin YE, Shen G, Bryant DA, Golbeck JH. Removal of PsaF alters forward electron transfer in photosystem I: evidence for fast reoxidation of QK-A in subunit deletion mutants of Synechococcus sp. PCC 7002. Biochemistry 2004; 43:1264-75. [PMID: 14756562 DOI: 10.1021/bi035431j] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Recent studies of point mutations in photosystem I have suggested that the two kinetic phases of phylloquinone reoxidation represent electron transfer in the two branches of cofactors. This interpretation implies that changes in the relative amplitudes of the two kinetic phases represent a change in the extent of electron transfer in the two branches. Using time-resolved electron paramagnetic resonance (EPR), this issue is investigated in subunit deletion mutants of Synechococcus sp. PCC 7002. The spin-polarized EPR signals of P(700)(+)A(1)(-) and P(700)(+)FeS(-), both at room temperature and in frozen solution, are altered by deletion of PsaF and/or PsaE, and the differences from the wild type are much more pronounced in PS I complexes isolated from the mutants using Triton X-100 rather than n-dodecyl beta-d-maltopyranoside. The changes in the transient EPR data for the mutant complexes are consistent with a significant fraction of reaction centers showing (i) faster electron transfer from A(1)(-) to F(X), (ii) slower forward electron transfer from A(0)(-) to A(1), and (iii) slightly altered quinone hyperfine couplings, possibly as a result of a change in the hydrogen bonding. The fraction of fast electron transfer and its dependence on the isolation procedure are estimated approximately from simulations of the room temperature EPR data. The results are discussed in terms of possible models for the electron transfer. It is suggested that the detergent-induced fraction of fast electron transfer is most likely due to alteration of the environment of the quinone in the PsaA branch of cofactors and is not the result of a change in the directionality of electron transfer.
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Affiliation(s)
- Art Van Der Est
- Department of Chemistry, Brock University, 500 Glenridge Avenue, St. Catharines, Ontario, Canada L2S 3A1.
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Poluektov OG, Utschig LM, Dubinskij AA, Thurnauer MC. ENDOR of Spin-Correlated Radical Pairs in Photosynthesis at High Magnetic Field: A Tool for Mapping Electron Transfer Pathways. J Am Chem Soc 2004; 126:1644-5. [PMID: 14871090 DOI: 10.1021/ja039309j] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
A new phenomenon has been detected in the time-resolved electron-nuclear double resonance (ENDOR) spectra of the spin-correlated radical pairs in photosynthetic reaction center proteins. The observed effects result from both increased resolution and orientational selectivity provided by high magnetic field EPR and are manifest as specific, derivative-type lines in the ENDOR spectrum. Importantly, the positions and amplitudes of these lines contain information on the interaction of a particular nucleus with both correlated electron spins. Thus, spin density delocalization in the protein environment between the donor and acceptor in the SCRP can be revealed via SCRP ENDOR, providing a unique opportunity to probe the electron-transfer pathways in natural and artificial photosynthetic assemblies.
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Affiliation(s)
- Oleg G Poluektov
- Chemistry Division, Argonne National Laboratory, 9700 South Cass Avenue, Argonne, IL 60439, USA.
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Xu W, Chitnis P, Valieva A, van der Est A, Pushkar YN, Krzystyniak M, Teutloff C, Zech SG, Bittl R, Stehlik D, Zybailov B, Shen G, Golbeck JH. Electron transfer in cyanobacterial photosystem I: I. Physiological and spectroscopic characterization of site-directed mutants in a putative electron transfer pathway from A0 through A1 to FX. J Biol Chem 2003; 278:27864-75. [PMID: 12721305 DOI: 10.1074/jbc.m302962200] [Citation(s) in RCA: 72] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The Photosystem I (PS I) reaction center contains two branches of nearly symmetric cofactors bound to the PsaA and PsaB heterodimer. From the x-ray crystal structure it is known that Trp697PsaA and Trp677PsaB are pi-stacked with the head group of the phylloquinones and are H-bonded to Ser692PsaA and Ser672PsaB, whereas Arg694PsaA and Arg674PsaB are involved in a H-bonded network of side groups that connects the binding environments of the phylloquinones and FX. The mutants W697FPsaA, W677FPsaB, S692CPsaA, S672CPsaB, R694APsaA, and R674APsaB were constructed and characterized. All mutants grew photoautotrophically, yet all showed diminished growth rates compared with the wild-type, especially at higher light intensities. EPR and electron nuclear double resonance (ENDOR) studies at both room temperature and in frozen solution showed that the PsaB mutants were virtually identical to the wild-type, whereas significant effects were observed in the PsaA mutants. Spin polarized transient EPR spectra of the P700+A1- radical pair show that none of the mutations causes a significant change in the orientation of the measured phylloquinone. Pulsed ENDOR spectra reveal that the W697FPsaA mutation leads to about a 5% increase in the hyperfine coupling of the methyl group on the phylloquinone ring, whereas the S692CPsaA mutation causes a similar decrease in this coupling. The changes in the methyl hyperfine coupling are also reflected in the transient EPR spectra of P700+A1- and the CW EPR spectra of photoaccumulated A1-. We conclude that: (i) the transient EPR spectra at room temperature are predominantly from radical pairs in the PsaA branch of cofactors; (ii) at low temperature the electron cycle involving P700 and A1 similarly occurs along the PsaA branch of cofactors; and (iii) mutation of amino acids in close contact with the PsaA side quinone leads to changes in the spin density distribution of the reduced quinone observed by EPR.
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Affiliation(s)
- Wu Xu
- Department of Biochemistry, Biophysics, and Molecular Biology, Iowa State University, Ames, Iowa 50011, USA
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