1
|
Ultrafast infrared spectroscopy in photosynthesis. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2014; 1847:2-11. [PMID: 24973600 DOI: 10.1016/j.bbabio.2014.06.006] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/14/2014] [Revised: 06/17/2014] [Accepted: 06/18/2014] [Indexed: 11/22/2022]
Abstract
In recent years visible pump/mid-infrared (IR) probe spectroscopy has established itself as a key technology to unravel structure-function relationships underlying the photo-dynamics of complex molecular systems. In this contribution we review the most important applications of mid-infrared absorption difference spectroscopy with sub-picosecond time-resolution to photosynthetic complexes. Considering several examples, such as energy transfer in photosynthetic antennas and electron transfer in reaction centers and even more intact structures, we show that the acquisition of ultrafast time resolved mid-IR spectra has led to new insights into the photo-dynamics of the considered systems and allows establishing a direct link between dynamics and structure, further strengthened by the possibility of investigating the protein response signal to the energy or electron transfer processes. This article is part of a Special Issue entitled: Vibrational spectroscopies and bioenergetic systems.
Collapse
|
2
|
Lewis KLM, Ogilvie JP. Probing Photosynthetic Energy and Charge Transfer with Two-Dimensional Electronic Spectroscopy. J Phys Chem Lett 2012; 3:503-10. [PMID: 26286055 DOI: 10.1021/jz201592v] [Citation(s) in RCA: 71] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/19/2023]
Abstract
Two-dimensional electronic spectroscopy (2DES) has emerged as a powerful method for elucidating the structure-function relationship in photosynthetic systems. In this Perspective, we discuss features of two-dimensional spectroscopy that make it highly suited to address questions about the underlying electronic structure that guides energy- and charge-transfer processes in light-harvesting materials. We briefly describe a pulse-shaping-based implementation of two-dimensional spectroscopy that is making the method widely accessible to problems spanning frequency regimes from the ultraviolet to the mid-infrared. We illustrate the utility of 2DES in the context of our recent studies of the primary energy-transfer and charge separation events in the photosystem II reaction center, discussing remaining challenges and speculating about exciting future directions for the field of multidimensional spectroscopy.
Collapse
Affiliation(s)
- Kristin L M Lewis
- Department of Physics and Biophysics, University of Michigan, Ann Arbor, Michigan 48109-1040, United States
| | - Jennifer P Ogilvie
- Department of Physics and Biophysics, University of Michigan, Ann Arbor, Michigan 48109-1040, United States
| |
Collapse
|
3
|
Kitagawa Y, Matsuda K, Hasegawa JY. Theoretical study of the excited states of the photosynthetic reaction center in photosystem II: Electronic structure, interactions, and their origin. Biophys Chem 2011; 159:227-36. [DOI: 10.1016/j.bpc.2011.06.011] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2011] [Revised: 06/17/2011] [Accepted: 06/17/2011] [Indexed: 11/29/2022]
|
4
|
Herascu N, Ahmouda S, Picorel R, Seibert M, Jankowiak R, Zazubovich V. Effects of the Distributions of Energy or Charge Transfer Rates on Spectral Hole Burning in Pigment–Protein Complexes at Low Temperatures. J Phys Chem B 2011; 115:15098-109. [DOI: 10.1021/jp208142k] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Nicoleta Herascu
- Department of Physics, Concordia University, 7141 Sherbrooke Street West, Montreal, Quebec H4B 1R6 Canada
| | - Somaya Ahmouda
- Department of Physics, Concordia University, 7141 Sherbrooke Street West, Montreal, Quebec H4B 1R6 Canada
| | - Rafael Picorel
- Estacion Experimental Aula Dei (CSIC), Avda. Montañana, 50059 Zaragoza, Spain
- National Renewable Energy Laboratory, Golden, Colorado 80401, United States
| | - Michael Seibert
- National Renewable Energy Laboratory, Golden, Colorado 80401, United States
| | - Ryszard Jankowiak
- Department of Chemistry, Kansas State University, Manhattan, Kansas 66506, United States
| | - Valter Zazubovich
- Department of Physics, Concordia University, 7141 Sherbrooke Street West, Montreal, Quebec H4B 1R6 Canada
| |
Collapse
|
5
|
Saito K, Kikuchi T, Nakayama M, Mukai K, Sumi H. A single chlorophyll in each of the core antennas CP43 and CP47 transferring excitation energies to the reaction center in Photosystem II of photosynthesis. J Photochem Photobiol A Chem 2006. [DOI: 10.1016/j.jphotochem.2005.10.038] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
|
6
|
Abstract
Oxygenic photosynthesis, the principal converter of sunlight into chemical energy on earth, is catalyzed by four multi-subunit membrane-protein complexes: photosystem I (PSI), photosystem II (PSII), the cytochrome b(6)f complex, and F-ATPase. PSI generates the most negative redox potential in nature and largely determines the global amount of enthalpy in living systems. PSII generates an oxidant whose redox potential is high enough to enable it to oxidize H(2)O, a substrate so abundant that it assures a practically unlimited electron source for life on earth. During the last century, the sophisticated techniques of spectroscopy, molecular genetics, and biochemistry were used to reveal the structure and function of the two photosystems. The new structures of PSI and PSII from cyanobacteria, algae, and plants has shed light not only on the architecture and mechanism of action of these intricate membrane complexes, but also on the evolutionary forces that shaped oxygenic photosynthesis.
Collapse
Affiliation(s)
- Nathan Nelson
- Department of Biochemistry, George S. Wise Faculty of Life Sciences, Tel Aviv University, Tel Aviv 69978, Israel.
| | | |
Collapse
|
7
|
Akimoto S, Mimuro M. Application of Time-resolved Polarization Fluorescence Spectroscopy in the Femtosecond Range to Photosynthetic Systems. Photochem Photobiol 2006; 83:163-70. [PMID: 16643087 DOI: 10.1562/2006-02-28-ir-825] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Time-resolved polarization fluorescence spectroscopy in the femtosecond range was applied to a photosynthetic antenna system. Specific signals of excited states were obtained by simultaneous measurements of fluorescence rise and decay curves and polarized spectroscopy. Relaxation processes of carotenoids, energy transfer from carotenoids to chlorophyll (Chl) a, and energy migration among pigment pools of Chl a and Chl b were clearly resolved. Two new characteristics of carotenoid molecules were revealed only by anisotropy measurements. A new singlet excited state between the well known S2 (1Bu(+)) and S1 (2Ag(-)) states was resolved by an intermediary anisotropy (r(t) = 0.30) for siphonaxanthin in chloroplasts of Codium fragile. Time-dependent changes in anisotropy with an initial value of 0.52 (r(0) = 0.52) were recorded during the relaxation of lutein molecules in the light-harvesting complexes II of Arabidopsis thaliana, and this was interpreted as a strong interaction between two lutein molecules in the pigment-protein complexes. Other examples of the application of this method were also discussed.
Collapse
Affiliation(s)
- Seiji Akimoto
- Division of Biotechnology and Macromolecular Chemistry, Graduate School of Engineering, Hokkaido University, Sapporo, Japan
| | | |
Collapse
|
8
|
|
9
|
Groot ML, Pawlowicz NP, van Wilderen LJGW, Breton J, van Stokkum IHM, van Grondelle R. Initial electron donor and acceptor in isolated Photosystem II reaction centers identified with femtosecond mid-IR spectroscopy. Proc Natl Acad Sci U S A 2005; 102:13087-92. [PMID: 16135567 PMCID: PMC1196200 DOI: 10.1073/pnas.0503483102] [Citation(s) in RCA: 154] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2005] [Indexed: 11/18/2022] Open
Abstract
Despite the apparent similarity between the plant Photosystem II reaction center (RC) and its purple bacterial counterpart, we show in this work that the mechanism of charge separation is very different for the two photosynthetic RCs. By using femtosecond visible-pump-mid-infrared probe spectroscopy in the region of the chlorophyll ester and keto modes, between 1,775 and 1,585 cm(-1), with 150-fs time resolution, we show that the reduction of pheophytin occurs on a 0.6- to 0.8-ps time scale, whereas P+, the precursor state for water oxidation, is formed after approximately 6 ps. We conclude therefore that in the Photosystem II RC the primary charge separation occurs between the "accessory chlorophyll" Chl(D1) and the pheophytin on the so-called active branch.
Collapse
Affiliation(s)
- Marie Louise Groot
- Faculty of Sciences, Vrije Universiteit, 1081 HV, Amsterdam, The Netherlands.
| | | | | | | | | | | |
Collapse
|
10
|
Raszewski G, Saenger W, Renger T. Theory of optical spectra of photosystem II reaction centers: location of the triplet state and the identity of the primary electron donor. Biophys J 2004; 88:986-98. [PMID: 15556979 PMCID: PMC1305170 DOI: 10.1529/biophysj.104.050294] [Citation(s) in RCA: 134] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Based on the structural analysis of photosystem II of Thermosynechococcus elongatus, a detailed calculation of optical properties of reaction-center (D1-D2) complexes is presented applying a theory developed previously. The calculations of absorption, linear dichroism, circular dichroism, fluorescence spectra, all at 6 K, and the temperature-dependence of the absorption spectrum are used to extract the local optical transition energies of the reaction-center pigments, the so-called site energies, from experimental data. The site energies are verified by calculations and comparison with seven additional independent experiments. Exciton relaxation and primary electron transfer in the reaction center are studied using the site energies. The calculations are used to interpret transient optical data. Evidence is provided for the accessory chlorophyll of the D1-branch as being the primary electron donor and the location of the triplet state at low temperatures.
Collapse
Affiliation(s)
- Grzegorz Raszewski
- Institut für Chemie (Kristallographie), Freie Universität Berlin, Berlin, Germany
| | | | | |
Collapse
|
11
|
Müller MG, Niklas J, Lubitz W, Holzwarth AR. Ultrafast transient absorption studies on Photosystem I reaction centers from Chlamydomonas reinhardtii. 1. A new interpretation of the energy trapping and early electron transfer steps in Photosystem I. Biophys J 2004; 85:3899-922. [PMID: 14645079 PMCID: PMC1303691 DOI: 10.1016/s0006-3495(03)74804-8] [Citation(s) in RCA: 153] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The energy transfer and charge separation kinetics in core Photosystem I (PSI) particles of Chlamydomonas reinhardtii has been studied using ultrafast transient absorption in the femtosecond-to-nanosecond time range. Although the energy transfer processes in the antenna are found to be generally in good agreement with previous interpretations, we present evidence that the interpretation of the energy trapping and electron transfer processes in terms of both kinetics and mechanisms has to be revised substantially as compared to current interpretations in the literature. We resolved for the first time i), the transient difference spectrum for the excited reaction center state, and ii), the formation and decay of the primary radical pair and its intermediate spectrum directly from measurements on open PSI reaction centers. It is shown that the dominant energy trapping lifetime due to charge separation is only 6-9 ps, i.e., by a factor of 3 shorter than assumed so far. The spectrum of the first radical pair shows the expected strong bleaching band at 680 nm which decays again in the next electron transfer step. We show furthermore that the early electron transfer processes up to approximately 100 ps are more complex than assumed so far. Several possibilities are discussed for the intermediate redox states and their sequence which involve oxidation of P700 in the first electron transfer step, as assumed so far, or only in the second electron transfer step, which would represent a fundamental change from the presently assumed mechanism. To explain the data we favor the inclusion of an additional redox state in the electron transfer scheme. Thus we distinguish three different redox intermediates on the timescale up to 100 ps. At this level no final conclusion as to the exact mechanism and the nature of the intermediates can be drawn, however. From comparison of our data with fluorescence kinetics in the literature we also propose a reversible first charge separation step which has been excluded so far for open PSI reaction centers. For the first time an ultrafast 150-fs equilibration process, occurring among exciton states in the reaction center proper, upon direct excitation of the reaction center at 700 nm, has been resolved. Taken together the data call for a fundamental revision of the present understanding of the energy trapping and early electron transfer kinetics in the PSI reaction center. Due to the fact that it shows the fastest trapping time observed so far of any intact PSI particle, the PSI core of C. reinhardtii seems to be best suited to further characterize the electron transfer steps and mechanisms in the reaction center of PSI.
Collapse
Affiliation(s)
- Marc G Müller
- Max-Planck-Institut für Bioanorganische Chemie, Stiftstr 34-36, D-45470 Mülheim ad Ruhr, Germany
| | | | | | | |
Collapse
|
12
|
Riley K, Jankowiak R, Rätsep M, Small GJ, Zazubovich V. Evidence for Highly Dispersive Primary Charge Separation Kinetics and Gross Heterogeneity in the Isolated PS II Reaction Center of Green Plants. J Phys Chem B 2004. [DOI: 10.1021/jp049562l] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Affiliation(s)
- K. Riley
- Ames Laboratory, USDOE and Department of Chemistry, Iowa State University, Ames, Iowa 50011, and Institute of Physics, University of Tartu, 142 Riia Street, 51014 Tartu, Estonia
| | - R. Jankowiak
- Ames Laboratory, USDOE and Department of Chemistry, Iowa State University, Ames, Iowa 50011, and Institute of Physics, University of Tartu, 142 Riia Street, 51014 Tartu, Estonia
| | - M. Rätsep
- Ames Laboratory, USDOE and Department of Chemistry, Iowa State University, Ames, Iowa 50011, and Institute of Physics, University of Tartu, 142 Riia Street, 51014 Tartu, Estonia
| | - G. J. Small
- Ames Laboratory, USDOE and Department of Chemistry, Iowa State University, Ames, Iowa 50011, and Institute of Physics, University of Tartu, 142 Riia Street, 51014 Tartu, Estonia
| | - V. Zazubovich
- Ames Laboratory, USDOE and Department of Chemistry, Iowa State University, Ames, Iowa 50011, and Institute of Physics, University of Tartu, 142 Riia Street, 51014 Tartu, Estonia
| |
Collapse
|
13
|
Andrizhiyevskaya EG, Frolov D, van Grondelle R, Dekker JP. On the role of the CP47 core antenna in the energy transfer and trapping dynamics of Photosystem II. Phys Chem Chem Phys 2004. [DOI: 10.1039/b411977k] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
|
14
|
van Mourik F, Groot ML, van Grondelle R, Dekker JP, van Stokkum IH. Global and target analysis of fluorescence measurements on photosystem 2 reaction centers upon red excitation. Phys Chem Chem Phys 2004. [DOI: 10.1039/b407633h] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
|
15
|
Zazubovich V, Jankowiak R, Riley K, Picorel R, Seibert M, Small GJ. How Fast Is Excitation Energy Transfer in the Photosystem II Reaction Center in the Low Temperature Limit? Hole Burning vs Photon Echo. J Phys Chem B 2003. [DOI: 10.1021/jp022231t] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- V. Zazubovich
- Ames Laboratory, U.S. Department of Energy and Department of Chemistry, Iowa State University, Ames, Iowa 50011, National Renewable Energy Laboratory, Golden, Colorado 80401, and E. E. Aula Dei, CSIC, Apdo. 202, 50080 Zaragoza, Spain
| | - R. Jankowiak
- Ames Laboratory, U.S. Department of Energy and Department of Chemistry, Iowa State University, Ames, Iowa 50011, National Renewable Energy Laboratory, Golden, Colorado 80401, and E. E. Aula Dei, CSIC, Apdo. 202, 50080 Zaragoza, Spain
| | - K. Riley
- Ames Laboratory, U.S. Department of Energy and Department of Chemistry, Iowa State University, Ames, Iowa 50011, National Renewable Energy Laboratory, Golden, Colorado 80401, and E. E. Aula Dei, CSIC, Apdo. 202, 50080 Zaragoza, Spain
| | - R. Picorel
- Ames Laboratory, U.S. Department of Energy and Department of Chemistry, Iowa State University, Ames, Iowa 50011, National Renewable Energy Laboratory, Golden, Colorado 80401, and E. E. Aula Dei, CSIC, Apdo. 202, 50080 Zaragoza, Spain
| | - M. Seibert
- Ames Laboratory, U.S. Department of Energy and Department of Chemistry, Iowa State University, Ames, Iowa 50011, National Renewable Energy Laboratory, Golden, Colorado 80401, and E. E. Aula Dei, CSIC, Apdo. 202, 50080 Zaragoza, Spain
| | - G. J. Small
- Ames Laboratory, U.S. Department of Energy and Department of Chemistry, Iowa State University, Ames, Iowa 50011, National Renewable Energy Laboratory, Golden, Colorado 80401, and E. E. Aula Dei, CSIC, Apdo. 202, 50080 Zaragoza, Spain
| |
Collapse
|
16
|
Jankowiak R, Rätsep M, Hayes J, Zazubovich V, Picorel R, Seibert M, Small GJ. Primary Charge-Separation Rate at 5 K in Isolated Photosystem II Reaction Centers Containing Five and Six Chlorophyll a Molecules. J Phys Chem B 2003. [DOI: 10.1021/jp021787d] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- R. Jankowiak
- Ames Laboratory, USDOE, and Department of Chemistry, Iowa State University, Ames, Iowa 50011, Institute of Physics, University of Tartu, 51014 Tartu, Estonia, E. E. Aula Dei (CSIC), Apdo. 202, 50080 Zaragoza, Spain, and National Renewable Energy Laboratory, Golden, Colorado 80401
| | - M. Rätsep
- Ames Laboratory, USDOE, and Department of Chemistry, Iowa State University, Ames, Iowa 50011, Institute of Physics, University of Tartu, 51014 Tartu, Estonia, E. E. Aula Dei (CSIC), Apdo. 202, 50080 Zaragoza, Spain, and National Renewable Energy Laboratory, Golden, Colorado 80401
| | - J. Hayes
- Ames Laboratory, USDOE, and Department of Chemistry, Iowa State University, Ames, Iowa 50011, Institute of Physics, University of Tartu, 51014 Tartu, Estonia, E. E. Aula Dei (CSIC), Apdo. 202, 50080 Zaragoza, Spain, and National Renewable Energy Laboratory, Golden, Colorado 80401
| | - V. Zazubovich
- Ames Laboratory, USDOE, and Department of Chemistry, Iowa State University, Ames, Iowa 50011, Institute of Physics, University of Tartu, 51014 Tartu, Estonia, E. E. Aula Dei (CSIC), Apdo. 202, 50080 Zaragoza, Spain, and National Renewable Energy Laboratory, Golden, Colorado 80401
| | - R. Picorel
- Ames Laboratory, USDOE, and Department of Chemistry, Iowa State University, Ames, Iowa 50011, Institute of Physics, University of Tartu, 51014 Tartu, Estonia, E. E. Aula Dei (CSIC), Apdo. 202, 50080 Zaragoza, Spain, and National Renewable Energy Laboratory, Golden, Colorado 80401
| | - M. Seibert
- Ames Laboratory, USDOE, and Department of Chemistry, Iowa State University, Ames, Iowa 50011, Institute of Physics, University of Tartu, 51014 Tartu, Estonia, E. E. Aula Dei (CSIC), Apdo. 202, 50080 Zaragoza, Spain, and National Renewable Energy Laboratory, Golden, Colorado 80401
| | - G. J. Small
- Ames Laboratory, USDOE, and Department of Chemistry, Iowa State University, Ames, Iowa 50011, Institute of Physics, University of Tartu, 51014 Tartu, Estonia, E. E. Aula Dei (CSIC), Apdo. 202, 50080 Zaragoza, Spain, and National Renewable Energy Laboratory, Golden, Colorado 80401
| |
Collapse
|
17
|
Barter LMC, Durrant JR, Klug DR. A quantitative structure-function relationship for the Photosystem II reaction center: supermolecular behavior in natural photosynthesis. Proc Natl Acad Sci U S A 2003; 100:946-51. [PMID: 12538865 PMCID: PMC298706 DOI: 10.1073/pnas.0136891100] [Citation(s) in RCA: 70] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Light-induced charge separation is the primary photochemical event of photosynthesis. Efficient charge separation in photosynthetic reaction centers requires the balancing of electron and excitation energy transfer processes, and in Photosystem II (PSII), these processes are particularly closely entangled. Calculations that treat the cofactors of the PSII reaction center as a supermolecular complex allow energy and electron transfer reactions to be described in a unified way. This calculational approach is shown to be in good agreement with experimentally observed energy and electron transfer dynamics. This supermolecular view also correctly predicts the effect of changing the redox potentials of cofactors by site-directed mutagenesis, thus providing a unified and quantitative structure-function relationship for the PSII reaction center.
Collapse
Affiliation(s)
- Laura M C Barter
- Department of Chemistry, Imperial College, London SW7 2AY, United Kingdom
| | | | | |
Collapse
|
18
|
Zehetner A, Scheer H, Siffel P, Vacha F. Photosystem II reaction center with altered pigment-composition: reconstitution of a complex containing five chlorophyll a per two pheophytin a with modified chlorophylls. BIOCHIMICA ET BIOPHYSICA ACTA 2002; 1556:21-8. [PMID: 12351215 DOI: 10.1016/s0005-2728(02)00282-7] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Pigment-depleted Photosystem II reaction centers (PS II-RCs) from a higher plant (pea) containing five chlorophyll a (Chl) per two pheophytin a (Phe), were treated with Chl and several derivatives under exchange conditions [FEBS Lett. 434 (1998) 88]. The resulting reconstituted complexes were compared to those obtained by pigment exchange of "conventional" PS II-RCs containing six Chl per two Phe. (1) The extraction of one Chl is fully reversible. (2) The site of extraction is the same as the one into which previously extraneous pigments have been exchanged, most likely the peripheral D1-H118. (3) Introducing an efficient quencher (Ni-Chl) into this site results in only 25% reduction of fluorescence, indicating incomplete energy equilibration among the "core" and peripheral chlorophylls.
Collapse
Affiliation(s)
- Andrea Zehetner
- Department Biologie I-Botanik, Universität München, Menzinger Str. 67, D-80638, Munich, Germany
| | | | | | | |
Collapse
|
19
|
Jankowiak R, Hayes JM, Small GJ. An Excitonic Pentamer Model for the Core Qy States of the Isolated Photosystem II Reaction Center. J Phys Chem B 2002. [DOI: 10.1021/jp020050l] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- R. Jankowiak
- Ames LaboratoryUSDOE and Department of Chemistry, Iowa State University, Ames, Iowa 50011
| | - J. M. Hayes
- Ames LaboratoryUSDOE and Department of Chemistry, Iowa State University, Ames, Iowa 50011
| | - G. J. Small
- Ames LaboratoryUSDOE and Department of Chemistry, Iowa State University, Ames, Iowa 50011
| |
Collapse
|
20
|
Wang J, Gosztola D, Ruffle SV, Hemann C, Seibert M, Wasielewski MR, Hille R, Gustafson TL, Sayre RT. Functional asymmetry of photosystem II D1 and D2 peripheral chlorophyll mutants of Chlamydomonas reinhardtii. Proc Natl Acad Sci U S A 2002; 99:4091-6. [PMID: 11904453 PMCID: PMC122653 DOI: 10.1073/pnas.062056899] [Citation(s) in RCA: 42] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2001] [Accepted: 01/31/2002] [Indexed: 11/18/2022] Open
Abstract
The peripheral accessory chlorophylls (Chls) of the photosystem II (PSII) reaction center (RC) are coordinated by a pair of symmetry-related histidine residues (D1-H118 and D2-H117). These Chls participate in energy transfer from the proximal antennae complexes (CP43 and CP47) to the RC core chromophores. In addition, one or both of the peripheral Chls are redox-active and participate in a low-quantum-yield electron transfer cycle around PSII. We demonstrate that conservative mutations of the D2-H117 residue result in decreased Chl fluorescence quenching efficiency attributed to reduced accumulation of the peripheral accessory Chl cation, Chl(Z)(+). In contrast, identical symmetry-related mutations at residue D1-H118 had no effect on Chl fluorescence yield or quenching kinetics. Mutagenesis of the D2-H117 residue also altered the line width of the Chl(Z)(+) EPR signal, but the line shape of the D1-H118Q mutant remained unchanged. The D1-H118 and D2-H117 mutations also altered energy transfer properties in PSII RCs. Unlike wild type or the D1-H118Q mutant, D2-H117N RCs exhibited a reduced CD doublet in the red region of Chl absorbance band, indicative of reduced energetic coupling between P680 and the peripheral accessory Chl. In addition, transient absorption measurements of D2-H117N RCs, excited on the blue side of the Chl absorbance band, exhibited a ( approximately 400 fs) pheophytin Q(X) band bleach lifetime component not seen in wild-type or D1-H118Q RCs. The origin of this component may be related to delayed fast-energy equilibration of the excited state between the core pigments of this mutant.
Collapse
Affiliation(s)
- Jun Wang
- Department of Plant Biology, Ohio State University, Columbus, OH 43210, USA
| | | | | | | | | | | | | | | | | |
Collapse
|
21
|
Diner BA, Rappaport F. Structure, dynamics, and energetics of the primary photochemistry of photosystem II of oxygenic photosynthesis. ANNUAL REVIEW OF PLANT BIOLOGY 2002; 53:551-80. [PMID: 12221988 DOI: 10.1146/annurev.arplant.53.100301.135238] [Citation(s) in RCA: 256] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/20/2023]
Abstract
Recent progress in two-dimensional and three-dimensional electron and X-ray crystallography of Photosystem II (PSII) core complexes has led to major advances in the structural definition of this integral membrane protein complex. Despite the overall structural and kinetic similarity of the PSII reaction centers to their purple non-sulfur photosynthetic bacterial homologues, the different cofactors and subtle differences in their spatial arrangement result in significant differences in the energetics and mechanism of primary charge separation. In this review we discuss some of the recent spectroscopic, structural, and mutagenic work on the primary and secondary electron transfer reactions in PSII, stressing what is experimentally novel, what new insights have appeared, and where questions of interpretation remain.
Collapse
Affiliation(s)
- Bruce A Diner
- CR&D, Experimental Station, E. I. du Pont de Nemours & Co., Wilmington, Delaware 19880-0173, USA.
| | | |
Collapse
|
22
|
Barter L, Schilstra M, Barber J, Durrant J, Klug D. Are the trapping dynamics in Photosystem II sensitive to QA redox potential? J Photochem Photobiol A Chem 2001. [DOI: 10.1016/s1010-6030(01)00506-8] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
|
23
|
Prokhorenko VI, Holzwarth AR. Primary Processes and Structure of the Photosystem II Reaction Center: A Photon Echo Study,. J Phys Chem B 2000. [DOI: 10.1021/jp002323n] [Citation(s) in RCA: 155] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Valentin I. Prokhorenko
- Max-Planck-Institut für Strahlenchemie, Stiftstrasse 34-36, D-45413 Mülheim a.d. Ruhr, Germany
| | - Alfred R. Holzwarth
- Max-Planck-Institut für Strahlenchemie, Stiftstrasse 34-36, D-45413 Mülheim a.d. Ruhr, Germany
| |
Collapse
|
24
|
Jankowiak R, Rätsep M, Picorel R, Seibert M, Small GJ. Excited States of the 5-Chlorophyll Photosystem II Reaction Center. J Phys Chem B 1999. [DOI: 10.1021/jp9906738] [Citation(s) in RCA: 45] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- R. Jankowiak
- Ames Laboratory−U.S. Department of Energy and Department of Chemistry, Iowa State University, Ames, Iowa 50011, E. E. Aula Dei, CSIC, Apdo. 202, 50080-Zaragoza, Spain, and National Renewable Energy Laboratory, Golden, Colorado 80401
| | - M. Rätsep
- Ames Laboratory−U.S. Department of Energy and Department of Chemistry, Iowa State University, Ames, Iowa 50011, E. E. Aula Dei, CSIC, Apdo. 202, 50080-Zaragoza, Spain, and National Renewable Energy Laboratory, Golden, Colorado 80401
| | - R. Picorel
- Ames Laboratory−U.S. Department of Energy and Department of Chemistry, Iowa State University, Ames, Iowa 50011, E. E. Aula Dei, CSIC, Apdo. 202, 50080-Zaragoza, Spain, and National Renewable Energy Laboratory, Golden, Colorado 80401
| | - M. Seibert
- Ames Laboratory−U.S. Department of Energy and Department of Chemistry, Iowa State University, Ames, Iowa 50011, E. E. Aula Dei, CSIC, Apdo. 202, 50080-Zaragoza, Spain, and National Renewable Energy Laboratory, Golden, Colorado 80401
| | - G. J. Small
- Ames Laboratory−U.S. Department of Energy and Department of Chemistry, Iowa State University, Ames, Iowa 50011, E. E. Aula Dei, CSIC, Apdo. 202, 50080-Zaragoza, Spain, and National Renewable Energy Laboratory, Golden, Colorado 80401
| |
Collapse
|
25
|
Greenfield SR, Seibert M, Wasielewski MR. Time-Resolved Absorption Changes of the Pheophytin Qx Band in Isolated Photosystem II Reaction Centers at 7 K: Energy Transfer and Charge Separation. J Phys Chem B 1999. [DOI: 10.1021/jp990962w] [Citation(s) in RCA: 41] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Scott R. Greenfield
- Chemical Sciences and Technology Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, Basic Sciences Center, National Renewable Energy Laboratory, Golden, Colorado 80401-3393, Chemistry Division, Argonne National Laboratory, Argonne, Illinois 60439-4831, and Department of Chemistry, Northwestern University, Evanston, Illinois 60208-3113
| | - Michael Seibert
- Chemical Sciences and Technology Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, Basic Sciences Center, National Renewable Energy Laboratory, Golden, Colorado 80401-3393, Chemistry Division, Argonne National Laboratory, Argonne, Illinois 60439-4831, and Department of Chemistry, Northwestern University, Evanston, Illinois 60208-3113
| | - Michael R. Wasielewski
- Chemical Sciences and Technology Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, Basic Sciences Center, National Renewable Energy Laboratory, Golden, Colorado 80401-3393, Chemistry Division, Argonne National Laboratory, Argonne, Illinois 60439-4831, and Department of Chemistry, Northwestern University, Evanston, Illinois 60208-3113
| |
Collapse
|
26
|
van Brederode ME, van Grondelle R. New and unexpected routes for ultrafast electron transfer in photosynthetic reaction centers. FEBS Lett 1999; 455:1-7. [PMID: 10428460 DOI: 10.1016/s0014-5793(99)00810-8] [Citation(s) in RCA: 64] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Abstract
In photosynthetic reaction centers, the excitation with light leads to the formation of a charge separated state across the photosynthetic membrane. For the reaction center of purple non-sulphur bacteria, it was previously generally assumed that this primary charge separation could only start with the excitation of the so-called special pair of bacteriochlorophyll molecules located in the heart of the RC. However, recently new and ultrafast pathways of charge separation have been discovered in the bacterial RC that are driven directly by the excited state of the accessory monomeric bacteriochlorophyll present in the active branch of cofactors. These results demonstrate that the route for energy conversion in photosynthesis can be much more flexible than previously thought. We suggest that the existence of multiple charge separation routes is particularly relevant for the mechanism of charge separation in the photosystem II reaction center of higher plants.
Collapse
Affiliation(s)
- M E van Brederode
- Department of Biophysics and Physics of Complex Systems, Vrije Universiteit and Institute of Molecular Biological Sciences (IMBW), Vrije Universiteit, Amsterdam, The Netherlands
| | | |
Collapse
|
27
|
Mimuro M, Akimoto S, Yamazaki I, Miyashita H, Miyachi S. Fluorescence properties of chlorophyll d-dominating prokaryotic alga, acaryochloris marina: studies using time-resolved fluorescence spectroscopy on intact cells. BIOCHIMICA ET BIOPHYSICA ACTA 1999; 1412:37-46. [PMID: 10354492 DOI: 10.1016/s0005-2728(99)00048-1] [Citation(s) in RCA: 52] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Antenna components and the primary electron donor of the photosystem (PS) II in the Chlorophyll (Chl) d-dominating prokaryote, Acaryochloris marina, were studied using time-resolved fluorescence spectroscopy in the ps time range. By selective excitation of Chl a or Chl d, differences in fluorescence properties were clearly resolved. At physiological temperature, energy transfer was confirmed by a red shift of emission maximum among PS II antenna components, and the equilibrium of energy distribution among Chl a and Chl d was established within 30 ps. A fluorescence component that can be assigned to delayed fluorescence (DF) was observed at 10 ns after the excitation; however, it was not necessarily resolved by the decay kinetics. At -196 degrees C, a red shift of emission maximum was reproduced but the equilibrium of energy distribution was not detected. DF was resolved in the wavelength region corresponding to Chl a by spectra and by decay kinetics. The lifetime of the DF was estimated to be approx. 15 ns, and the peaks were located at 681 and 695 nm, significantly shorter wavelengths than those of Chl d. These findings strongly suggest that an origin of DF is Chl a, and Chl a is most probably the primary electron donor in the PS II reaction center (RC). These results indicate that the constitution of PS II RC in this alga is essentially identical to that of other oxygenic photosynthetic organisms.
Collapse
Affiliation(s)
- M Mimuro
- Department of Physics, Biology and Informatics, Faculty of Science, Yamaguchi University, Yoshida, Yamaguchi 753-8512, Japan
| | | | | | | | | |
Collapse
|
28
|
Affiliation(s)
- M H Vos
- INSERM U451, Laboratoire d'Optique Appliquée, Ecole Polytechnique-ENSTA, 91761, Palaiseau Cedex, France.
| | | |
Collapse
|
29
|
van Brederode ME, van Mourik F, van Stokkum IH, Jones MR, van Grondelle R. Multiple pathways for ultrafast transduction of light energy in the photosynthetic reaction center of Rhodobacter sphaeroides. Proc Natl Acad Sci U S A 1999; 96:2054-9. [PMID: 10051593 PMCID: PMC26735 DOI: 10.1073/pnas.96.5.2054] [Citation(s) in RCA: 85] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
A pathway of electron transfer is described that operates in the wild-type reaction center (RC) of the photosynthetic bacterium Rhodobacter sphaeroides. The pathway does not involve the excited state of the special pair dimer of bacteriochlorophylls (P*), but instead is driven by the excited state of the monomeric bacteriochlorophyll (BA*) present in the active branch of pigments along which electron transfer occurs. Pump-probe experiments were performed at 77 K on membrane-bound RCs by using different excitation wavelengths, to investigate the formation of the charge separated state P+HA-. In experiments in which P or BA was selectively excited at 880 nm or 796 nm, respectively, the formation of P+HA- was associated with similar time constants of 1.5 ps and 1. 7 ps. However, the spectral changes associated with the two time constants are very different. Global analysis of the transient spectra shows that a mixture of P+BA- and P* is formed in parallel from BA* on a subpicosecond time scale. In contrast, excitation of the inactive branch monomeric bacteriochlorophyll (BB) and the high exciton component of P (P+) resulted in electron transfer only after relaxation to P*. The multiple pathways for primary electron transfer in the bacterial RC are discussed with regard to the mechanism of charge separation in the RC of photosystem II from higher plants.
Collapse
Affiliation(s)
- M E van Brederode
- Faculty of Sciences, Vrije Universiteit, de Boelelaan 1081, 1081 HV Amsterdam, The Netherlands
| | | | | | | | | |
Collapse
|
30
|
Peterman EJ, van Amerongen H, van Grondelle R, Dekker JP. The nature of the excited state of the reaction center of photosystem II of green plants: a high-resolution fluorescence spectroscopy study. Proc Natl Acad Sci U S A 1998; 95:6128-33. [PMID: 9600929 PMCID: PMC27597 DOI: 10.1073/pnas.95.11.6128] [Citation(s) in RCA: 84] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/1997] [Accepted: 03/16/1998] [Indexed: 02/07/2023] Open
Abstract
We studied the electronically excited state of the isolated reaction center of photosystem II with high-resolution fluorescence spectroscopy at 5 K and compared the obtained spectral features with those obtained earlier for the primary electron donor. The results show that there is a striking resemblance between the emitting and charge-separating states in the photosystem II reaction center, such as a very similar shape of the phonon wing with characteristic features at 19 and 80 cm-1, almost identical frequencies of a number of vibrational modes, a very similar double-Gaussian shape of the inhomogeneous distribution function, and relatively strong electron-phonon coupling for both states. We suggest that the emission at 5 K originates either from an exciton state delocalized over the inactive branch of the photosystem or from a fraction of the primary electron donor that is long-lived at 5 K. The latter possibility can be explained by a distribution of the free energy difference of the primary charge separation reaction around zero. Both possibilities are in line with the idea that the state that drives primary charge separation in the reaction center of photosystem II is a collective state, with contributions from all chlorophyll molecules in the central part of the complex.
Collapse
Affiliation(s)
- E J Peterman
- Department of Physics and Astronomy and Institute for Molecular Biological Sciences, Vrije Universiteit, De Boelelaan 1081, 1081 HV Amsterdam, The Netherlands
| | | | | | | |
Collapse
|
31
|
Groot ML, van Grondelle R, Leegwater JA, van Mourik F. Radical Pair Quantum Yield in Reaction Centers of Photosystem II of Green Plants and of the Bacterium Rhodobacter sphaeroides. Saturation Behavior with Sub-picosecond Pulses. J Phys Chem B 1997. [DOI: 10.1021/jp971113g] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Marie-Louise Groot
- Department of Physics and Astronomy and Institute of Molecular Biological Sciences, Vrije Universiteit, De Boelelaan 1081, 1081 HV Amsterdam, The Netherlands
| | - Rienk van Grondelle
- Department of Physics and Astronomy and Institute of Molecular Biological Sciences, Vrije Universiteit, De Boelelaan 1081, 1081 HV Amsterdam, The Netherlands
| | - Jan-Adriaan Leegwater
- Department of Physics and Astronomy and Institute of Molecular Biological Sciences, Vrije Universiteit, De Boelelaan 1081, 1081 HV Amsterdam, The Netherlands
| | - Frank van Mourik
- Department of Physics and Astronomy and Institute of Molecular Biological Sciences, Vrije Universiteit, De Boelelaan 1081, 1081 HV Amsterdam, The Netherlands
| |
Collapse
|
32
|
Donovan B, Walker LA, Kaplan D, Bouvier M, Yocum CF, Sension RJ. Structure and Function in the Isolated Reaction Center Complex of Photosystem II. 1. Ultrafast Fluorescence Measurements of PSII. J Phys Chem B 1997. [DOI: 10.1021/jp971112o] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Brent Donovan
- Department of Chemistry, Department of Biology, and Center for Ultrafast Optical Science, University of Michigan, Ann Arbor, Michigan 48109, MEDOX ELECTRO-OPTICS, 3940 Varsity Drive, Ann Arbor, Michigan 48108, and Alliage, 77 rue de Cardinal Lemoine, 75005 Paris, France
| | - Larry A. Walker
- Department of Chemistry, Department of Biology, and Center for Ultrafast Optical Science, University of Michigan, Ann Arbor, Michigan 48109, MEDOX ELECTRO-OPTICS, 3940 Varsity Drive, Ann Arbor, Michigan 48108, and Alliage, 77 rue de Cardinal Lemoine, 75005 Paris, France
| | - Daniel Kaplan
- Department of Chemistry, Department of Biology, and Center for Ultrafast Optical Science, University of Michigan, Ann Arbor, Michigan 48109, MEDOX ELECTRO-OPTICS, 3940 Varsity Drive, Ann Arbor, Michigan 48108, and Alliage, 77 rue de Cardinal Lemoine, 75005 Paris, France
| | - Marcel Bouvier
- Department of Chemistry, Department of Biology, and Center for Ultrafast Optical Science, University of Michigan, Ann Arbor, Michigan 48109, MEDOX ELECTRO-OPTICS, 3940 Varsity Drive, Ann Arbor, Michigan 48108, and Alliage, 77 rue de Cardinal Lemoine, 75005 Paris, France
| | - Charles F. Yocum
- Department of Chemistry, Department of Biology, and Center for Ultrafast Optical Science, University of Michigan, Ann Arbor, Michigan 48109, MEDOX ELECTRO-OPTICS, 3940 Varsity Drive, Ann Arbor, Michigan 48108, and Alliage, 77 rue de Cardinal Lemoine, 75005 Paris, France
| | - Roseanne J. Sension
- Department of Chemistry, Department of Biology, and Center for Ultrafast Optical Science, University of Michigan, Ann Arbor, Michigan 48109, MEDOX ELECTRO-OPTICS, 3940 Varsity Drive, Ann Arbor, Michigan 48108, and Alliage, 77 rue de Cardinal Lemoine, 75005 Paris, France
| |
Collapse
|
33
|
Groot ML, Eijckelhoff C, Dekker JP. Charge separation in the reaction center of photosystem II studied as a function of temperature. Proc Natl Acad Sci U S A 1997; 94:4389-94. [PMID: 9113999 PMCID: PMC20732 DOI: 10.1073/pnas.94.9.4389] [Citation(s) in RCA: 59] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
In photosystem II of green plants the key photosynthetic reaction consists of the transfer of an electron from the primary donor called P680 to a nearby pheophytin molecule. We analyzed the temperature dependence of this reaction by subpicosecond transient absorption spectroscopy over the temperature range 20-240 K using isolated photosystem II reaction centers from spinach. After excitation in the red edge of the Qy absorption band, the decay of the excited state can conveniently be described by two kinetic components that both accelerate with temperature. This temperature behavior differs remarkably from that observed in purple bacterial reaction centers. We attribute the first component, which accelerates from 2.6 ps at 20 K to 0.4 ps at 240 K, to charge separation after direct excitation of P680, and explain its temperature dependence by an intermediate that lies in energy above the singlet-excited P680 and that possibly has charge-transfer character. The second component accelerates from 120 ps at 20 K to 18 ps at 240 K and is attributed to charge separation after direct excitation of the "trap" state near-degenerate with P680 and subsequent slow energy transfer from this trap state to P680. We suggest that the slow energy transfer from the trap state to P680 plays an important role in the kinetics of radical pair formation at room temperature.
Collapse
Affiliation(s)
- M L Groot
- Department of Physics and Astronomy and Institute of Molecular Biological Sciences, Vrije Universiteit, De Boelelaan 1081, 1081 HV Amsterdam, The Netherlands
| | | | | |
Collapse
|
34
|
Greenfield SR, Seibert M, Govindjee, Wasielewski MR. Direct Measurement of the Effective Rate Constant for Primary Charge Separation in Isolated Photosystem II Reaction Centers. J Phys Chem B 1997. [DOI: 10.1021/jp962982t] [Citation(s) in RCA: 64] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Scott R. Greenfield
- Chemistry Division, Argonne National Laboratory, Argonne, Illinois 60439-4831, Basic Sciences Center, National Renewable Energy Laboratory, Golden, Colorado 80401-3393, Department of Plant Biology, University of Illinois, Urbana, Illinois 61801-3707, and Department of Chemistry, Northwestern University, Evanston, Illinois 60208-3113
| | - Michael Seibert
- Chemistry Division, Argonne National Laboratory, Argonne, Illinois 60439-4831, Basic Sciences Center, National Renewable Energy Laboratory, Golden, Colorado 80401-3393, Department of Plant Biology, University of Illinois, Urbana, Illinois 61801-3707, and Department of Chemistry, Northwestern University, Evanston, Illinois 60208-3113
| | - Govindjee
- Chemistry Division, Argonne National Laboratory, Argonne, Illinois 60439-4831, Basic Sciences Center, National Renewable Energy Laboratory, Golden, Colorado 80401-3393, Department of Plant Biology, University of Illinois, Urbana, Illinois 61801-3707, and Department of Chemistry, Northwestern University, Evanston, Illinois 60208-3113
| | - Michael R. Wasielewski
- Chemistry Division, Argonne National Laboratory, Argonne, Illinois 60439-4831, Basic Sciences Center, National Renewable Energy Laboratory, Golden, Colorado 80401-3393, Department of Plant Biology, University of Illinois, Urbana, Illinois 61801-3707, and Department of Chemistry, Northwestern University, Evanston, Illinois 60208-3113
| |
Collapse
|
35
|
Eijckelhoff C, Vacha F, van Grondelle R, Dekker JP, Barber J. Spectroscopic characterization of a 5 Chl a photosystem II reaction center complex. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 1997. [DOI: 10.1016/s0005-2728(96)00144-2] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
|