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Yakovlev AG, Taisova AS. Downhill excitation energy flow in reaction centers of purple bacteria Rhodospirillum rubrum G9. BIOCHIMICA ET BIOPHYSICA ACTA. BIOENERGETICS 2024; 1865:149499. [PMID: 39069149 DOI: 10.1016/j.bbabio.2024.149499] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/13/2024] [Revised: 07/24/2024] [Accepted: 07/24/2024] [Indexed: 07/30/2024]
Abstract
Using femtosecond differential spectroscopy, excitation energy transfer in reaction centers (RCs) of the carotenoidless strain of purple bacteria Rhodospirillum rubrum G9 was studied at room temperature. Excitation and probing of the Qy, Qx and Soret absorption bands of the RCs were carried out by pulses with duration of 25-30 fs. Modeling of ΔA (light - dark) kinetics made it possible to estimate the characteristic time of various stages of excitation energy transformation. It is shown that the dynamics of the downhill energy flow in the RCs is determined both by the internal energy conversion Soret→ Qx → Qy in each cofactor and by the energy transfer H* → B* → P* (H - bacteriopheophytin, B - bacteriochlorophyll a, P - bacteriochlorophyll a dimer) between cofactors. The transfer of energy between the upper excited levels (Soret and Qx) of the cofactors accelerates its arrival to the lower exciton level of the P, from where charge separation begins. It turned out that all conversion and energy transfer processes occur within 40-160 fs: the conversion Soret → Qx occurs in 40-50 fs, the conversion Qx → Qy occurs in 100-140 fs, the transfer H* → B* has a time constant of 80-120 fs, and the transfer B* → P* has a time constant of 130-160 fs. The rate of energy transfer between the upper excited levels is close to the rate of transfer between Qy levels.
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Affiliation(s)
- Andrei G Yakovlev
- Lomonosov Moscow State University, Belozersky Institute of Physico-Chemical Biology, Leninskie Gory, 119991 Moscow, Russian Federation.
| | - Alexandra S Taisova
- Lomonosov Moscow State University, Belozersky Institute of Physico-Chemical Biology, Leninskie Gory, 119991 Moscow, Russian Federation
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2
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Dubas K, Szewczyk S, Białek R, Burdziński G, Jones MR, Gibasiewicz K. Antagonistic Effects of Point Mutations on Charge Recombination and a New View of Primary Charge Separation in Photosynthetic Proteins. J Phys Chem B 2021; 125:8742-8756. [PMID: 34328746 PMCID: PMC8389993 DOI: 10.1021/acs.jpcb.1c03978] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
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Light-induced electron-transfer
reactions were investigated in
wild-type and three mutant Rhodobacter sphaeroides reaction centers with the secondary electron acceptor (ubiquinone
QA) either removed or permanently reduced. Under such conditions,
charge separation between the primary electron donor (bacteriochlorophyll
dimer, P) and the electron acceptor (bacteriopheophytin, HA) was followed by P+HA– →
PHA charge recombination. Two reaction centers were used
that had different single amino-acid mutations that brought about
either a 3-fold acceleration in charge recombination compared to that
in the wild-type protein, or a 3-fold deceleration. In a third mutant
in which the two single amino-acid mutations were combined, charge
recombination was similar to that in the wild type. In all cases,
data from transient absorption measurements were analyzed using similar
models. The modeling included the energetic relaxation of the charge-separated
states caused by protein dynamics and evidenced the appearance of
an intermediate charge-separated state, P+BA–, with BA being the bacteriochlorophyll
located between P and HA. In all cases, mixing of the states
P+BA– and P+HA– was observed and explained in terms of
electron delocalization over BA and HA. This
delocalization, together with picosecond protein relaxation, underlies
a new view of primary charge separation in photosynthesis.
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Affiliation(s)
- K Dubas
- Faculty of Physics, Adam Mickiewicz University, ul. Uniwersytetu Poznanskiego 2, 61-614 Poznań, Poland.,Department of Optometry, Poznan University of Medical Sciences, ul. Rokietnicka 5d, 60-806 Poznań, Poland
| | - S Szewczyk
- Faculty of Physics, Adam Mickiewicz University, ul. Uniwersytetu Poznanskiego 2, 61-614 Poznań, Poland
| | - R Białek
- Faculty of Physics, Adam Mickiewicz University, ul. Uniwersytetu Poznanskiego 2, 61-614 Poznań, Poland
| | - G Burdziński
- Faculty of Physics, Adam Mickiewicz University, ul. Uniwersytetu Poznanskiego 2, 61-614 Poznań, Poland
| | - M R Jones
- School of Biochemistry, Medical Sciences Building, University of Bristol, University Walk, Bristol, BS8 1TD, U.K
| | - K Gibasiewicz
- Faculty of Physics, Adam Mickiewicz University, ul. Uniwersytetu Poznanskiego 2, 61-614 Poznań, Poland
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3
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Ultrafast structural changes within a photosynthetic reaction centre. Nature 2021; 589:310-314. [PMID: 33268896 DOI: 10.1038/s41586-020-3000-7] [Citation(s) in RCA: 46] [Impact Index Per Article: 15.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2018] [Accepted: 09/28/2020] [Indexed: 01/29/2023]
Abstract
Photosynthetic reaction centres harvest the energy content of sunlight by transporting electrons across an energy-transducing biological membrane. Here we use time-resolved serial femtosecond crystallography1 using an X-ray free-electron laser2 to observe light-induced structural changes in the photosynthetic reaction centre of Blastochloris viridis on a timescale of picoseconds. Structural perturbations first occur at the special pair of chlorophyll molecules of the photosynthetic reaction centre that are photo-oxidized by light. Electron transfer to the menaquinone acceptor on the opposite side of the membrane induces a movement of this cofactor together with lower amplitude protein rearrangements. These observations reveal how proteins use conformational dynamics to stabilize the charge-separation steps of electron-transfer reactions.
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Lu Y, Goodson C, Blankenship RE, Gross ML. Primary and Higher Order Structure of the Reaction Center from the Purple Phototrophic Bacterium Blastochloris viridis: A Test for Native Mass Spectrometry. J Proteome Res 2018; 17:1615-1623. [PMID: 29466012 PMCID: PMC5911391 DOI: 10.1021/acs.jproteome.7b00897] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The reaction center (RC) from the phototrophic bacterium Blastochloris viridis was the first integral membrane protein complex to have its structure determined by X-ray crystallography and has been studied extensively since then. It is composed of four protein subunits, H, M, L, and C, as well as cofactors, including bacteriopheophytin (BPh), bacteriochlorophyll (BCh), menaquinone, ubiquinone, heme, carotenoid, and Fe. In this study, we utilized mass spectrometry-based proteomics to study this protein complex via bottom-up sequencing, intact protein mass analysis, and native MS ligand-binding analysis. Its primary structure shows a series of mutations, including an unusual alteration and extension on the C-terminus of the M-subunit. In terms of quaternary structure, proteins such as this containing many cofactors serve to test the ability to introduce native-state protein assemblies into the gas phase because the cofactors will not be retained if the quaternary structure is seriously perturbed. Furthermore, this specific RC, under native MS, exhibits a strong ability not only to bind the special pair but also to preserve the two peripheral BCh's.
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Affiliation(s)
- Yue Lu
- Department of Chemistry, Washington University in St. Louis, St. Louis, MO 63130, USA
- Photosynthetic Antenna Research Center, Washington University in St. Louis, St. Louis, Missouri 63130, USA
| | - Carrie Goodson
- Photosynthetic Antenna Research Center, Washington University in St. Louis, St. Louis, Missouri 63130, USA
- Department of Biology, Washington University in St. Louis, St. Louis, MO 63130, USA
| | - Robert E. Blankenship
- Department of Chemistry, Washington University in St. Louis, St. Louis, MO 63130, USA
- Photosynthetic Antenna Research Center, Washington University in St. Louis, St. Louis, Missouri 63130, USA
- Department of Biology, Washington University in St. Louis, St. Louis, MO 63130, USA
| | - Michael L. Gross
- Department of Chemistry, Washington University in St. Louis, St. Louis, MO 63130, USA
- Photosynthetic Antenna Research Center, Washington University in St. Louis, St. Louis, Missouri 63130, USA
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Khatypov RA, Khristin AM, Fufina TY, Shuvalov VA. An Alternative Pathway of Light-Induced Transmembrane Electron Transfer in Photosynthetic Reaction Centers of Rhodobacter sphaeroides. BIOCHEMISTRY (MOSCOW) 2017; 82:692-697. [PMID: 28601078 DOI: 10.1134/s0006297917060050] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
In the absorption spectrum of Rhodobacter sphaeroides reaction centers, a minor absorption band was found with a maximum at 1053 nm. The amplitude of this band is ~10,000 times less and its half-width is comparable to that of the long-wavelength absorption band of the primary electron donor P870. When the primary electron donor is excited by femtosecond light pulses at 870 nm, the absorption band at 1053 nm is increased manifold during the earliest stages of charge separation. The growth of this absorption band in difference absorption spectra precedes the appearance of stimulated emission at 935 nm and the appearance of the absorption band of anion-radical BA- at 1020 nm, reported earlier by several researchers. When reaction centers are illuminated with 1064 nm light, the absorption spectrum undergoes changes indicating reduction of the primary electron acceptor QA, with the primary electron donor P870 remaining neutral. These photoinduced absorption changes reflect the formation of the long-lived radical state PBAHAQA-.
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Affiliation(s)
- R A Khatypov
- Institute of Basic Biological Problems, Russian Academy of Sciences, Pushchino, Moscow Region, 142290, Russia.
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ZHANG JIAN, ABE TOSHIYUKI, KANEKO MASAO. Charge Transfer of Tetraphenylporphyrin Zinc Complexes Incorporated in a Poly(2-vinylpyridine) Matrix. J PORPHYR PHTHALOCYA 2012. [DOI: 10.1002/(sici)1099-1409(199803/04)2:2<93::aid-jpp81>3.0.co;2-x] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
An indium tin oxide (ITO) electrode was coated by a poly(2-vinylpyridine) (P-2VP) film incorporating tetraphenylporphyrin zinc ( ZnTPP ) as a redox center. A cyclic voltammogram (CV) exhibited a couple of redox waves at 0.7 V (vs Ag / AgCl ). The potential-step chronoamperospectrometry (PSCAS) measurement was carried out on the modified electrode immersed in a 0.1 M LiClO 4 aqueous solution at pH 3.5 under argon atmosphere. Assuming a random distribution of the redox species in the macromolecular structure, the charge transfer distance between the adjacent ZnTPP complexes was obtained as 1.08 nm. The charge hopping distance between the redox centers (1.01 nm) and the bounded motion distance (0.07 nm after 2h) were obtained according to their different response time in the electrochemical measurement. Considering the contributions from both the charge hopping and bounded motion, the second order rate constant of electron hopping was 4.1 × 104 M−1s−1.
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Affiliation(s)
- JIAN ZHANG
- Faculty of Science, Ibaraki University, Mito, Ibaraki 310, Japan
| | - TOSHIYUKI ABE
- Department of Applied Chemistry, Saitama University, Shimo-Ohkubo, Urawa 338, Japan
| | - MASAO KANEKO
- Faculty of Science, Ibaraki University, Mito, Ibaraki 310, Japan
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Structural and dynamic aspects of electron transfer in proteins — highly organized natural nanostructures. Russ Chem Bull 2012. [DOI: 10.1007/s11172-011-0199-3] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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8
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Fujitsuka M, Majima T. Photoinduced Electron Transfer Processes in Biological and Artificial Supramolecules. Supramol Chem 2012. [DOI: 10.1002/9780470661345.smc090] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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Trissl HW. Spatial correlation between primary redox components in reaction centers of Rhodopseudomonas sphaeroides measured by two electrical methods in the nanosecond range. Proc Natl Acad Sci U S A 2010; 80:7173-7. [PMID: 16593393 PMCID: PMC390016 DOI: 10.1073/pnas.80.23.7173] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Relative distances between the the primary donor P, the intermediary pheophytin acceptor H, and the iron-quinone acceptor Q of bacterial reaction centers were determined by recording laser flash-induced photovoltages in two experimental systems with nanosecond time resolution. In one system a suspension of chromatophores was subjected to a light gradient and in the other system chromatophores were spread at a heptane/water interface. The 10-ns back reaction occurring in reaction centers with reduced Q could be time resolved. The initial photovoltage amplitude under conditions in which the charge separation proceeded up to the state [P(+)H(-)] was about (2/3) of that when it proceeded up to the state [P(+)HQ(-)]. If the amplitude of the photovoltage is considered to be proportional to the spatial displacement of charges, this result means that pheophytin lies closer to Q than to P.
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Affiliation(s)
- H W Trissl
- Universität Osnabrück, Schwerpunkt Biophysik, Albrechtstrasse 28, D-4500 Osnabrück, Federal Republic of Germany
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Shuvalov VA, Parson WW. Energies and kinetics of radical pairs involving bacteriochlorophyll and bacteriopheophytin in bacterial reaction centers. Proc Natl Acad Sci U S A 2010; 78:957-61. [PMID: 16592980 PMCID: PMC319924 DOI: 10.1073/pnas.78.2.957] [Citation(s) in RCA: 131] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Absorbance changes reflecting the formation of a transient radical-pair state, P(F), were measured in reaction centers from Rhodopseudomonas sphaeroides under conditions that blocked electron transfer to a later carrier (a quinone, Q). The temperature dependence of the absorbance changes suggests that P(F) is an equilibrium mixture of two states, which appear to be mainly (1)[P([unk])B([unk])] and (1)[P([unk])H([unk])]. P is a bacteriochlorophyll dimer, B is a bacteriochlorophyll absorbing at 800 nm, and H is a bacteriopheophytin. In the presence of Q([unk]), the energy of (1)[P([unk])B([unk])] is about 0.025 eV above that of (1)[P([unk])H([unk])], (1)[P([unk])H([unk])] can decay to a triplet state, P(R), which also is an equilibrium mixture of two states, separated by about 0.03 eV. The lower of these appears to be mainly a locally excited triplet state of P, (3)P; the upper state contains a major contribution from a triplet charge-transfer state, (3)[P([unk])B([unk])]. The temperature dependence of delayed fluorescence from P(R) indicates that (3)P lies 0.40 eV below the excited singlet state, P(*), which is about 0.05 eV above (1)[P([unk])H([unk])]. The (1,3)[P([unk])B([unk])] charge-transfer states thus appear to interact with the locally excited states of P and B to give singlet and triplet states that are separated in energy by about 0.35 eV. This is 10(6) times larger than the splitting between (1)[P([unk])H([unk])] and (3)[P([unk])H([unk])] and implies strong orbital overlap between P([unk]) and B([unk]). This is consistent with recent picosecond studies which suggest that electron transfer from P(*) to B occurs within 1 ps and is followed in 4 to 10 ps by electron transfer from B([unk]) to H.
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Affiliation(s)
- V A Shuvalov
- Department of Biochemistry, University of Washington, Seattle, Washington 98195
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Breton J, Martin JL, Migus A, Antonetti A, Orszag A. Femtosecond spectroscopy of excitation energy transfer and initial charge separation in the reaction center of the photosynthetic bacterium Rhodopseudomonas viridis. Proc Natl Acad Sci U S A 2010; 83:5121-5. [PMID: 16593728 PMCID: PMC323902 DOI: 10.1073/pnas.83.14.5121] [Citation(s) in RCA: 236] [Impact Index Per Article: 16.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Reaction centers from the photosynthetic bacterium Rhodopseudomonas viridis have been excited within the near-infrared absorption bands of the dimeric primary donor (P), of the "accessory" bacteriochlorophylls (B), and of the bacteriopheophytins (H) by using laser pulses of 150-fsec duration. The transfer of excitation energy between H, B, and P occurs in slightly less than 100 fsec and leads to the ultrafast formation of an excited state of P. This state is characterized by a broad absorption spectrum and exhibits stimulated emission. It decays in 2.8 +/- 0.2 psec with the simultaneous oxidation of the primary donor and reduction of the bacteriopheophytin acceptor, which have been monitored at 545, 675, 815, 830, and 1310 nm. Although a transient bleaching relaxing in 400 +/- 100 fsec is specifically observed upon excitation and observation in the 830-nm absorption band, we have found no indication that an accessory bacteriochlorophyll is involved as a resolvable intermediary acceptor in the primary electron transfer process.
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Affiliation(s)
- J Breton
- Service de Biophysique, Département de Biologie, Centre d'Etudes Nucléaires de Saclay, 91191 Gif-sur-Yvette Cedex, France
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Deprez J, Trissl HW, Breton J. Excitation trapping and primary charge stabilization in Rhodopseudomonas viridis cells, measured electrically with picosecond resolution. Proc Natl Acad Sci U S A 2010; 83:1699-703. [PMID: 16593665 PMCID: PMC323151 DOI: 10.1073/pnas.83.6.1699] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The transmembrane primary charge separation in the photosynthetic bacterium Rhodopseudomonas viridis was monitored by electric measurements of the light-gradient type [Trissl, H. W. & Kunze, U. (1985) Biochim. Biophys. Acta 806, 136-144]. Excitation of whole cells with 30-ps laser pulses at either 532 nm or 1064 nm gave rise to a biphasic increase of the photovoltage. The fast phase, contributing about 50% of the total, rose with an exponential time constant </=40 ps and was independent of the redox state of the quinone electron acceptor. It is assigned to the migration of the excitation energy in the antenna and its subsequent trapping by the reaction center, monitored by the ultrafast charge separation between the primary electron donor and the bacteriopheophytin intermediary acceptor. The slower phase (125 +/- 50 ps) only occurred when the quinone was oxidized and disappeared when it was reduced (either chemically or photochemically). It is assigned to the forward electron transfer from the bacteriopheophytin to the quinone. The relative amplitudes of these two electrogenic steps demonstrate that the bacteriopheophytin intermediary acceptor is located halfway between the primary donor and the quinone.
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Affiliation(s)
- J Deprez
- Service de Biophysique, Département de Biologie, Centre d'Etudes Nucléaire de Saclay, 91191 Gif-sur-Yvette Cedex, France
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Debenhofer J, Huber R, Michel H. Die strukturelle Grundlage der Lichtreaktionen in Bakterien. ACTA ACUST UNITED AC 2010. [DOI: 10.1002/nadc.19860340504] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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Gibasiewicz K, Pajzderska M, Karolczak J, Dobek A. Excitation and electron transfer in reaction centers from Rhodobacter sphaeroides probed and analyzed globally in the 1-nanosecond temporal window from 330 to 700 nm. Phys Chem Chem Phys 2009; 11:10484-93. [PMID: 19890535 DOI: 10.1039/b912431d] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Global analysis of a set of room temperature transient absorption spectra of Rhodobacter sphaeroides reaction centers, recorded in wide temporal and spectral ranges and triggered by femtosecond excitation of accessory bacteriochlorophylls at 800 nm, is presented. The data give a comprehensive review of all spectral dynamics features in the visible and near UV, from 330 to 700 nm, related to the primary events in the Rb. sphaeroides reaction center: excitation energy transfer from the accessory bacteriochlorophylls (B) to the primary donor (P), primary charge separation between the primary donor and primary acceptor (bacteriopheophytin, H), and electron transfer from the primary to the secondary electron acceptor (ubiquinone). In particular, engagement of the accessory bacteriochlorophyll in primary charge separation is shown as an intermediate electron acceptor, and the initial free energy gap of approximately 40 meV, between the states P(+)B(A)(-) and P(+)H(A)(-) is estimated. The size of this gap is shown to be constant for the whole 230 ps lifetime of the P(+)H(A)(-) state. The ultrafast spectral dynamics features recorded in the visible range are presented against a background of results from similar studies performed for the last two decades.
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Affiliation(s)
- K Gibasiewicz
- Department of Physics, Adam Mickiewicz University, ul. Umultowska 85, 61-614 Poznań, Poland.
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15
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Mechanism of Charge Separation in Purple Bacterial Reaction Centers. THE PURPLE PHOTOTROPHIC BACTERIA 2009. [DOI: 10.1007/978-1-4020-8815-5_19] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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Bixon M, Jortner J. Electron Transfer-from Isolated Molecules to Biomolecules. ADVANCES IN CHEMICAL PHYSICS 2007. [DOI: 10.1002/9780470141656.ch3] [Citation(s) in RCA: 232] [Impact Index Per Article: 13.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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Bignozzi CA, Schoonover JR, Scandola F. A Supramolecular Approach to Light Harvesting and Sensitization of Wide-Bandgap Semiconductors: Antenna Effects and Charge Separation. PROGRESS IN INORGANIC CHEMISTRY 2007. [DOI: 10.1002/9780470166451.ch1] [Citation(s) in RCA: 52] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
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Ohkubo K, Sintic PJ, Tkachenko NV, Lemmetyinen H, E W, Ou Z, Shao J, Kadish KM, Crossley MJ, Fukuzumi S. Photoinduced electron-transfer dynamics and long-lived CS states of donor–acceptor linked dyads and a triad containing a gold porphyrin in nonpolar solvents. Chem Phys 2006. [DOI: 10.1016/j.chemphys.2006.01.034] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Zinth W, Wachtveitl J. The First Picoseconds in Bacterial Photosynthesis?Ultrafast Electron Transfer for the Efficient Conversion of Light Energy. Chemphyschem 2005; 6:871-80. [PMID: 15884069 DOI: 10.1002/cphc.200400458] [Citation(s) in RCA: 129] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
In this Minireview, we describe the function of the bacterial reaction centre (RC) as the central photosynthetic energy-conversion unit by ultrafast spectroscopy combined with structural analysis, site-directed mutagenesis, pigment exchange and theoretical modelling. We show that primary energy conversion is a stepwise process in which an electron is transferred via neighbouring chromophores of the RC. A well-defined chromophore arrangement in a rigid protein matrix, combined with optimised energetics of the different electron carriers, allows a highly efficient charge-separation process. The individual molecular reactions at room temperature are well described by conventional electron-transfer theory.
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Affiliation(s)
- Wolfgang Zinth
- Department für Physik, Ludwig-Maximilians-Universität München, Oettingenstr. 67, 80538 München, Germany.
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21
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Di Donato M, Peluso A, Villani G. Electron Transfer between Quinones in Photosynthetic Reaction Centers. J Phys Chem B 2004. [DOI: 10.1021/jp036678t] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Mariangela Di Donato
- Dipartimento di Chimica, Università di Salerno, I-84081 Baronissi, Salerno, Italy,and Istituto per i Processi Chimico Fisici, IPCF, CNR, via G. Moruzzi 1, I-56124, Pisa, Italy
| | - Andrea Peluso
- Dipartimento di Chimica, Università di Salerno, I-84081 Baronissi, Salerno, Italy,and Istituto per i Processi Chimico Fisici, IPCF, CNR, via G. Moruzzi 1, I-56124, Pisa, Italy
| | - Giovanni Villani
- Dipartimento di Chimica, Università di Salerno, I-84081 Baronissi, Salerno, Italy,and Istituto per i Processi Chimico Fisici, IPCF, CNR, via G. Moruzzi 1, I-56124, Pisa, Italy
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22
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Di Donato M, Correa A, Peluso A. The role of the iron–histidine bridge in the early steps of photosynthesis. Chem Phys Lett 2003. [DOI: 10.1016/s0009-2614(02)01892-4] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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Paddon-Row MN. Orbital interactions and long-range electron transfer. ADVANCES IN PHYSICAL ORGANIC CHEMISTRY 2003. [DOI: 10.1016/s0065-3160(03)38001-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/07/2023]
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Franzen S, Stanley RJ. A theoretical explanation for quantum yield failure in bacterial photosynthetic reaction centers. Chem Phys 2002. [DOI: 10.1016/s0301-0104(01)00582-1] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Sebban P, Barbet JC. Intermediate states between P* and Pf in bacterial reaction centers, as detected by the fluorescence kinetics. FEBS Lett 2001. [DOI: 10.1016/0014-5793(84)80024-1] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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Shuvalov V, Klimov V, Dolan E, Parson W, Ke B. Nanosecond fluorescence and absorbance changes in photosystem II at low redox potential. FEBS Lett 2001. [DOI: 10.1016/0014-5793(80)80238-9] [Citation(s) in RCA: 96] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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27
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Boxer SG, Middendorf TR, Lockhart DJ. Reversible photochemical holeburning in Rhodopseudomonas viridis
reaction centers. FEBS Lett 2001. [DOI: 10.1016/0014-5793(86)80545-2] [Citation(s) in RCA: 64] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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28
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Wasielewski MR, Tiede DM. Sub-picosecond measurements of primary electron transfer in Rhodopseudomonas viridis
reaction centers using near-infrared excitation. FEBS Lett 2001. [DOI: 10.1016/0014-5793(86)80845-6] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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30
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Robert B, Lutz M, Tiede DM. Selective photochemical reduction of either of the two bacteriopheophytins in reaction centers of Rps. sphaeroides
R-26. FEBS Lett 2001. [DOI: 10.1016/0014-5793(85)80803-6] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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31
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Hörber J, Göbel W, Ogrodnik A, Michel-Beyerle M, Cogdell R. Time-resolved measurements of fluorescence from reaction centres of Rhodopseudomonas viridis
and the effect of menaquinone reduction. FEBS Lett 2001. [DOI: 10.1016/0014-5793(86)80418-5] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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33
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Dracheva SM, Drachev LA, Zaberezhnaya SM, Konstantincv AA, Semenov AY, Skulachev VP. Spectral, redox and kinetic characteristics of high-potential cytochrome c
hemes in Rhodopseudomonas viridis
reaction center. FEBS Lett 2001. [DOI: 10.1016/0014-5793(86)80862-6] [Citation(s) in RCA: 40] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
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34
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Thornber J, Seftor RE, Cogdell RJ. Intermediary electron carriers in the primary photosynthetic event of Rhodopseudomonas viridis. FEBS Lett 2001. [DOI: 10.1016/0014-5793(81)80609-6] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
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35
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Burning of a narrow spectral hole at 1.7 K in the absorbance band of the primary electron donor of Rhodopseudomonas viridis
reaction centers with blocked electron transfer. FEBS Lett 2001. [DOI: 10.1016/0014-5793(88)80171-6] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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36
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Skulachev VP. Energy transduction by the photosynthetic reaction center complex from Rhodopseudomonas viridis. FEBS Lett 2001. [DOI: 10.1016/0014-5793(87)81120-1] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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37
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Bernhardt K, Trissl H. Escape probability and trapping mechanism in purple bacteria: revisited. BIOCHIMICA ET BIOPHYSICA ACTA 2000; 1457:1-17. [PMID: 10692545 DOI: 10.1016/s0005-2728(99)00103-6] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Despite intensive research for decades, the trapping mechanism in the core complex of purple bacteria is still under discussion. In this article, it is attempted to derive a conceptionally simple model that is consistent with all basic experimental observations and that allows definite conclusions on the trapping mechanism. Some experimental data reported in the literature are conflicting or incomplete. Therefore we repeated two already published experiments like the time-resolved fluorescence decay in LH1-only purple bacteria Rhodospirillum rubrum and Rhodopseudomonas viridis chromatophores with open and closed (Q(A)(-)) reaction centers. Furthermore, we measured fluorescence excitation spectra for both species under the two redox-conditions. These data, all measured at room temperature, were analyzed by a target analysis based on a three-state model (antenna, primary donor, and radical pair). All states were allowed to react reversibly and their decay channels were taken into consideration. This leads to seven rate constants to be determined. It turns out that a unique set of numerical values of these rate constants can be found, when further experimental constraints are met simultaneously, i.e. the ratio of the fluorescence yields in the open and closed (Q(A)(-)) states F(m)/F(o) approximately 2 and the P(+)H(-)-recombination kinetics of 3-6 ns. The model allows to define and to quantify escape probabilities and the transfer equilibrium. We conclude that trapping in LH1-only purple bacteria is largely transfer-to-the-trap-limited. Furthermore, the model predicts properties of the reaction center (RC) in its native LH1-environment. Within the framework of our model, the predicted P(+)H(-)-recombination kinetics are nearly indistinguishable for a hypothetically isolated RC and an antenna-RC complex, which is in contrast to published experimental data for physically isolated RCs. Therefore RC preparations may display modified kinetic properties.
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Affiliation(s)
- K Bernhardt
- Abteilung Biophysik, Fachbereich Biologie/Chemie, University of Osnabrück, Barbarastr. 11, D-49069, Osnabrück, Germany
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39
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Gibasiewicz K, Brettel K, Dobek A, Leibl W. Re-examination of primary radical pair recombination in Rp. viridis with QA reduced. Chem Phys Lett 1999. [DOI: 10.1016/s0009-2614(99)01158-6] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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40
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Specific emission and quenching of photoexcited tetraphenylporphyrin derivatives incorporated in a Nafion film. J Photochem Photobiol A Chem 1998. [DOI: 10.1016/s1010-6030(98)00383-9] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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41
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Lin S, Jackson J, Taguchi AKW, Woodbury NW. Excitation Wavelength Dependent Spectral Evolution in Rhodobacter sphaeroides R-26 Reaction Centers at Low Temperatures: The Qy Transition Region. J Phys Chem B 1998. [DOI: 10.1021/jp980360x] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Su Lin
- Department of Chemistry and Biochemistry and the Center for the Study of Early Events in Photosynthesis, Arizona State University, Tempe, Arizona 85287-1604
| | - Jon Jackson
- Department of Chemistry and Biochemistry and the Center for the Study of Early Events in Photosynthesis, Arizona State University, Tempe, Arizona 85287-1604
| | - Aileen K. W. Taguchi
- Department of Chemistry and Biochemistry and the Center for the Study of Early Events in Photosynthesis, Arizona State University, Tempe, Arizona 85287-1604
| | - Neal W. Woodbury
- Department of Chemistry and Biochemistry and the Center for the Study of Early Events in Photosynthesis, Arizona State University, Tempe, Arizona 85287-1604
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42
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Till U, Klenina IB, Proskuryakov II, Hoff AJ, Hore PJ. Recombination Dynamics and EPR Spectra of the Primary Radical Pair in Bacterila Photosynthetic Reaction Centers with Blocked Electron Transfer to the Primary Acceptor. J Phys Chem B 1997. [DOI: 10.1021/jp970686q] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- U. Till
- Physical & Theoretical Chemistry Laboratory, Oxford University, Oxford OX1 3QZ, United Kingdom, Institute of Soil Science and Photosynthesis RAS, Pushchino 142292, Russia, and Department of Biophysics, Huygens Laboratory, Leiden University, 2300 RA Leiden, The Netherlands
| | - I. B. Klenina
- Physical & Theoretical Chemistry Laboratory, Oxford University, Oxford OX1 3QZ, United Kingdom, Institute of Soil Science and Photosynthesis RAS, Pushchino 142292, Russia, and Department of Biophysics, Huygens Laboratory, Leiden University, 2300 RA Leiden, The Netherlands
| | - I. I. Proskuryakov
- Physical & Theoretical Chemistry Laboratory, Oxford University, Oxford OX1 3QZ, United Kingdom, Institute of Soil Science and Photosynthesis RAS, Pushchino 142292, Russia, and Department of Biophysics, Huygens Laboratory, Leiden University, 2300 RA Leiden, The Netherlands
| | - A. J. Hoff
- Physical & Theoretical Chemistry Laboratory, Oxford University, Oxford OX1 3QZ, United Kingdom, Institute of Soil Science and Photosynthesis RAS, Pushchino 142292, Russia, and Department of Biophysics, Huygens Laboratory, Leiden University, 2300 RA Leiden, The Netherlands
| | - P. J. Hore
- Physical & Theoretical Chemistry Laboratory, Oxford University, Oxford OX1 3QZ, United Kingdom, Institute of Soil Science and Photosynthesis RAS, Pushchino 142292, Russia, and Department of Biophysics, Huygens Laboratory, Leiden University, 2300 RA Leiden, The Netherlands
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Chen E, Goldbeck RA, Kliger DS. Nanosecond time-resolved spectroscopy of biomolecular processes. ANNUAL REVIEW OF BIOPHYSICS AND BIOMOLECULAR STRUCTURE 1997; 26:327-55. [PMID: 9241422 DOI: 10.1146/annurev.biophys.26.1.327] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Over the past two decades, nanosecond absorption and vibrational spectroscopies have developed into powerful tools for monitoring the secondary, tertiary, and quaternary structural relaxations of biological macromolecules under near-physiological conditions of solvent and temperature. Observed through such methods, the dynamic response of a biomolecule to photoinitiated excursions from equilibrium can reveal valuable information about the structure-function relationship, information beyond that obtained from the static structures provided by X-ray crystallography, nuclear magnetic resonance spectroscopy, and other steady-state methods. Most recently, the development of ultra-sensitive polarization techniques for absorption spectroscopy has greatly enhanced the amount of time-resolved structural information that can be obtained from the broadened electronic spectra of biomolecules. This review examines nanosecond absorption, vibrational, and polarized absorption methods, and their applications to protein function and folding, emphasizing the complementary nature of information obtained from electronic and vibrational spectra measured on the nanosecond time scale.
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Affiliation(s)
- E Chen
- Department of Chemistry and Biochemistry, University of California, Santa Cruz 95064, USA
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44
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Frank HA, Chynwat V, Posteraro A, Hartwich G, Simonin I, Scheer H. Triplet state energy transfer between the primary donor and the carotenoid in Rhodobacter sphaeroides R-26.1 reaction centers exchanged with modified bacteriochlorophyll pigments and reconstituted with spheroidene. Photochem Photobiol 1996; 64:823-31. [PMID: 8931381 DOI: 10.1111/j.1751-1097.1996.tb01842.x] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
The dynamics of triplet energy transfer between the primary donor and the carotenoid were measured on several photosynthetic bacterial reaction center preparations from Rhodobacter sphaeroides: (a) wild-type strain 2.4.1, (b) strain R-26.1, (c) strain R-26.1 exchanged with 13(2)-hydroxy-[Zn]-bacteriochlorophyll at the accessory bacteriochlorophyll (BChl) sites and reconstituted with spheroidene and (d) strain R-26.1 exchanged with [3-vinyl]-13(2)-hydroxy-bacteriochlorophyll at the accessory BChl sites and reconstituted with spheroidene. The rise and decay times of the primary donor and carotenoid triplet-triplet absorption signals were monitored in the visible wavelength region between 538 and 555 nm as a function of temperature from 4 to 300 K. For the samples containing carotenoids, all of the decay times correspond well to the previously observed times for spheroidene (5 +/- 2 microseconds). The rise times of the carotenoid triplets were found in all cases to be biexponential and comprised of a strongly temperature-dependent component and a temperature-independent component. From a comparison of the behavior of the carotenoid-containing samples with that from the reaction center of the carotenoidless mutant Rb. sphaeroides R-26.1, the temperature-independent component has been assigned to the buildup of the primary donor triplet state resulting from charge recombination in the reaction center. Arrhenius plots of the buildup of the carotenoid triplet states were used to determine the activation energies for triplet energy transfer from the primary donor to the carotenoid. A model for the process of triplet energy transfer that is consistent with the data suggests that the activation barrier is strongly dependent on the triplet state energy of the accessory BChl pigment, BChlB.
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Affiliation(s)
- H A Frank
- Department of Chemistry, University of Connecticut, Storrs 06269-4060, USA.
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45
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Jirsakova V, Reiss-Husson F, Agalidis I, Vrieze J, Hoff AJ. Triplet states in reaction center, light-harvesting complex B875 and its spectral form B840 from Rubrivivax gelatinosus investigated by absorbance-detected electron spin resonance in zero magnetic field (ADMR). BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 1995. [DOI: 10.1016/0005-2728(95)00099-5] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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Abstract
Many oxidoreductases are constructed from (a) local sites of strongly coupled substrate-redox cofactor partners participating in exchange of electron pairs, (b) electron pair/single electron transducing redox centers, and (c) nonadiabatic, long-distance, single-electron tunneling between weakly coupled redox centers. The latter is the subject of an expanding experimental program that seeks to manipulate, test, and apply the parameters of theory. New results from the photosynthetic reaction center protein confirm that the electronic-tunneling medium appears relatively homogeneous, with any variances evident having no impact on function, and that control of intraprotein rates and directional specificity rests on a combination of distance, free energy, and reorganization energy. Interprotein electron transfer between cytochrome c and the reaction center and in lactate dehydrogenase, a typical oxidoreductase from yeast, are examined. Rates of interprotein electron transfer appear to follow intraprotein guidelines with the added essential provision of binding forces to bring the cofactors of the reacting proteins into proximity.
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Affiliation(s)
- C C Moser
- Johnson Research Foundation, University of Pennsylvania, Philadelphia 19104, USA
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47
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van Amerongen H, van Grondelle R. Transient absorption spectroscopy in study of processes and dynamics in biology. Methods Enzymol 1995; 246:201-26. [PMID: 7752925 DOI: 10.1016/0076-6879(95)46011-x] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Affiliation(s)
- H van Amerongen
- Department of Physics and Astronomy, Free University of Amsterdam, The Netherlands
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48
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Peloquin JM, Williams JC, Lin X, Alden RG, Taguchi AK, Allen JP, Woodbury NW. Time-dependent thermodynamics during early electron transfer in reaction centers from Rhodobacter sphaeroides. Biochemistry 1994; 33:8089-100. [PMID: 8025115 DOI: 10.1021/bi00192a014] [Citation(s) in RCA: 118] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
The temperature dependence of fluorescence on the picosecond to nanosecond time scale from the reaction centers of Rhodobacter sphaeroides strain R-26 and two mutants with elevated P/P+ midpoint potentials has been measured with picosecond time resolution. In all three samples, the kinetics of the fluorescence decay is complex and can only be well described with four or more exponential decay terms spanning the picosecond to nanosecond time range. Multiexponential fits are needed at all temperatures between 295 and 20 K. The complex decay kinetics are explained in terms of a dynamic solvation model in which the charge-separated state is stabilized after formation by protein conformational changes. Many of these motions have not had time to occur on the time scale of initial electron transfer and/or are frozen out at low temperature. This results in a time- and temperature-dependent enthalpy change between the excited singlet state and the charge-separated state that is the dominant term in the free energy difference between these states. Long-lived fluorescence is still observed even at 20 K, particularly for the high-potential mutants. This implies that the driving force for electron transfer on the nanosecond time scale at low temperature is less than 200 cm-1 (25 meV) in R-26 reaction centers and even smaller on the picosecond time scale or in the high-potential mutants.(ABSTRACT TRUNCATED AT 250 WORDS)
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Affiliation(s)
- J M Peloquin
- Department of Chemistry and Biochemistry, Arizona State University, Tempe 85287-1604
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49
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van den Brink J, Manikowski H, Gast P, Hoff A. Temperature-dependent electron spin polarization of the triplet state of the primary donor in Rhodopseudomonas viridis. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 1994. [DOI: 10.1016/0005-2728(94)90208-9] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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50
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Molecular Genetic Manipulation and Characterization of Mutant Photosynthetic Reaction Centers from Purple Nonsulfur Bacteria. ACTA ACUST UNITED AC 1994. [DOI: 10.1016/s1569-2558(08)60398-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register]
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