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Choudhury A, Santra S, Ghosh D. Understanding the Photoprocesses in Biological Systems: Need for Accurate Multireference Treatment. J Chem Theory Comput 2024; 20:4951-4964. [PMID: 38864715 DOI: 10.1021/acs.jctc.4c00027] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/13/2024]
Abstract
Light-matter interaction is crucial to life itself and revolves around many of the central processes in biology. The need for understanding these photochemical and photophysical processes cannot be overemphasized. Interaction of light with biological systems starts with the absorption of light and subsequent phenomena that occur in the excited states of the system. However, excited states are typically difficult to understand within the mean field approximation of quantum chemical methods. Therefore, suitable multireference methods and methodologies have been developed to understand these phenomena. In this Perspective, we will describe a few methods and methodologies suitable for these descriptions and discuss some persisting difficulties.
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Affiliation(s)
- Arpan Choudhury
- School of Chemical Sciences, Indian Association for the Cultivation of Science, Jadavpur, Kolkata 700032, India
| | - Supriyo Santra
- School of Chemical Sciences, Indian Association for the Cultivation of Science, Jadavpur, Kolkata 700032, India
| | - Debashree Ghosh
- School of Chemical Sciences, Indian Association for the Cultivation of Science, Jadavpur, Kolkata 700032, India
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Investigations of the Energy Transfer in the Phycobilisome Antenna of Arthrospira platensis Using Femtosecond Spectroscopy. APPLIED SCIENCES-BASEL 2020. [DOI: 10.3390/app10114045] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Understanding the energy transfer in phycobilisomes extracted from cyanobacteria can be used for building biomimetic hybrid systems for optimized solar energy collection and photocurrent amplification. In this paper, we applied time-resolved absorption and fluorescence spectroscopy to investigate the ultrafast dynamics in a hemidiscoidal phycobilisome obtained from Arthrospira platensis. We obtained the steady-state and time-resolved optical properties and identified the possible pathways of the excitation energy transfer in the phycobilisome and its components, phycocyanin and allophycocyanin. The transient absorption data were studied using global analysis and revealed the existence of ultrafast kinetics down to 850 fs in the phycobilisome. The fluorescence lifetimes in the nanosecond time-scale assigned to the final emitters in each sample were obtained from the time-correlated single photon counting fluorescence experiments.
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Abstract
Oxygenic photosynthesis is the principal converter of sunlight into chemical energy on Earth. Cyanobacteria and plants provide the oxygen, food, fuel, fibers, and platform chemicals for life on Earth. The conversion of solar energy into chemical energy is catalyzed by two multisubunit membrane protein complexes, photosystem I (PSI) and photosystem II (PSII). Light is absorbed by the pigment cofactors, and excitation energy is transferred among the antennae pigments and converted into chemical energy at very high efficiency. Oxygenic photosynthesis has existed for more than three billion years, during which its molecular machinery was perfected to minimize wasteful reactions. Light excitation transfer and singlet trapping won over fluorescence, radiation-less decay, and triplet formation. Photosynthetic reaction centers operate in organisms ranging from bacteria to higher plants. They are all evolutionarily linked. The crystal structure determination of photosynthetic protein complexes sheds light on the various partial reactions and explains how they are protected against wasteful pathways and why their function is robust. This review discusses the efficiency of photosynthetic solar energy conversion.
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Affiliation(s)
- Nathan Nelson
- Department of Biochemistry, George S. Wise Faculty of Life Sciences, Tel Aviv University, Tel Aviv 69978, Israel;
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Non-Photochemical Quenching Mechanisms in Intact Organisms as Derived from Ultrafast-Fluorescence Kinetic Studies. ADVANCES IN PHOTOSYNTHESIS AND RESPIRATION 2014. [DOI: 10.1007/978-94-017-9032-1_5] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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5
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Roberts GM, Williams CA, Paterson MJ, Ullrich S, Stavros VG. Comparing the ultraviolet photostability of azole chromophores. Chem Sci 2012. [DOI: 10.1039/c2sc01000c] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
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6
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Holzwarth AR, Schatz G, Brock H, Bittersmann E. Energy transfer and charge separation kinetics in photosystem I: Part 1: Picosecond transient absorption and fluorescence study of cyanobacterial photosystem I particles. Biophys J 2010; 64:1813-26. [PMID: 19431900 DOI: 10.1016/s0006-3495(93)81552-2] [Citation(s) in RCA: 104] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The energy transfer and charge separation kinetics of a photosystem I (PS I) core particle of an antenna size of 100 chlorophyll/P700 has been studied by combined fluorescence and transient absorption kinetics with picosecond resolution. This is the first combined picosecond study of transient absorption and fluorescence carried out on a PS I particle and the results are consistent with each other. The data were analyzed by both global lifetime and global target analysis procedures. In fluorescence major lifetime components were found to be 12 and 36 ps. The shorter-lived one shows a negative amplitude at long wavelengths and is attributed to an energy transfer process between pigments in the main antenna Chl pool and a small long-wavelength Chl pool emitting around 720 nm whereas the longer-lived component is assigned to the overall charge separation lifetime. The lifetimes resolved in transient absorption are 7-8 ps, 33 ps, and [unk]1 ns. The shortest-lived one is assigned to energy transfer between the same pigment pools as observed also in fluorescence kinetics, the middle component of 33 ps to the overall charge separation, and the long-lived component to the lifetime of the oxidized primary donor P700(+). The transient absorption data indicate an even faster, but kinetically unresolved energy transfer component in the main Chl pool with a lifetime <3 ps. Several kinetic models were tested on both the fluorescence and the picosecond absorption data by global target analysis procedures. A model where the long-wave pigments are spatially and kinetically connected with the reaction center P700 is favored over a model where P700 is connected more closely with the main Chl pool. Our data show that the charge separation kinetics in these PS I particles is essentially trap limited. The relevance of our data with respect to other time-resolved studies on PS I core particles is discussed, in particular with respect to the nature and function of the long-wave pigments. From the transient absorption data we do not see any evidence for the occurrence of a reduced Chl primary electron acceptor, but we also can not exclude that possibility, provided that reoxidation of that acceptor should occur within a time <40 ps.
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Affiliation(s)
- A R Holzwarth
- Max-Planck-Institut für Strahlenchemie, D-4330 Mülheim an der Ruhr, Germany
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Ostroumov EE, Fadeev VV, Khristin MS, Pashchenko VZ, Tusov VB. Fluorescence characteristics and photophysical parameters of light-harvesting chlorophyll a/b complex aggregates. Biophysics (Nagoya-shi) 2007. [DOI: 10.1134/s0006350907050028] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
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Zhang JM, Shiu YJ, Hayashi M, Liang KK, Chang CH, Gulbinas V, Yang CM, Yang TS, Wang HZ, Chen YT, Lin SH. Investigations of Ultrafast Exciton Dynamics in Allophycocyanin Trimer. J Phys Chem A 2001. [DOI: 10.1021/jp011266a] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Affiliation(s)
- J. M. Zhang
- Institute of Atomic and Molecular Sciences, Academia Sinica, Taipei, Taiwan, ROC, Department of Chemistry, National Taiwan University, Taipei, Taiwan, ROC, Center for Condensed Matter Sciences, National Taiwan University, Taipei, Taiwan, ROC, Institute of Physics, Vilnius, Lithuania, Institute of Botany, Academia Sinica, Taipei, Taiwan, ROC, and State Key Laboratory for Ultrafast Laser Spectroscopy, Zhongshan University, Quangzhou, PRC
| | - Y. J. Shiu
- Institute of Atomic and Molecular Sciences, Academia Sinica, Taipei, Taiwan, ROC, Department of Chemistry, National Taiwan University, Taipei, Taiwan, ROC, Center for Condensed Matter Sciences, National Taiwan University, Taipei, Taiwan, ROC, Institute of Physics, Vilnius, Lithuania, Institute of Botany, Academia Sinica, Taipei, Taiwan, ROC, and State Key Laboratory for Ultrafast Laser Spectroscopy, Zhongshan University, Quangzhou, PRC
| | - M. Hayashi
- Institute of Atomic and Molecular Sciences, Academia Sinica, Taipei, Taiwan, ROC, Department of Chemistry, National Taiwan University, Taipei, Taiwan, ROC, Center for Condensed Matter Sciences, National Taiwan University, Taipei, Taiwan, ROC, Institute of Physics, Vilnius, Lithuania, Institute of Botany, Academia Sinica, Taipei, Taiwan, ROC, and State Key Laboratory for Ultrafast Laser Spectroscopy, Zhongshan University, Quangzhou, PRC
| | - K. K. Liang
- Institute of Atomic and Molecular Sciences, Academia Sinica, Taipei, Taiwan, ROC, Department of Chemistry, National Taiwan University, Taipei, Taiwan, ROC, Center for Condensed Matter Sciences, National Taiwan University, Taipei, Taiwan, ROC, Institute of Physics, Vilnius, Lithuania, Institute of Botany, Academia Sinica, Taipei, Taiwan, ROC, and State Key Laboratory for Ultrafast Laser Spectroscopy, Zhongshan University, Quangzhou, PRC
| | - C. H. Chang
- Institute of Atomic and Molecular Sciences, Academia Sinica, Taipei, Taiwan, ROC, Department of Chemistry, National Taiwan University, Taipei, Taiwan, ROC, Center for Condensed Matter Sciences, National Taiwan University, Taipei, Taiwan, ROC, Institute of Physics, Vilnius, Lithuania, Institute of Botany, Academia Sinica, Taipei, Taiwan, ROC, and State Key Laboratory for Ultrafast Laser Spectroscopy, Zhongshan University, Quangzhou, PRC
| | - V. Gulbinas
- Institute of Atomic and Molecular Sciences, Academia Sinica, Taipei, Taiwan, ROC, Department of Chemistry, National Taiwan University, Taipei, Taiwan, ROC, Center for Condensed Matter Sciences, National Taiwan University, Taipei, Taiwan, ROC, Institute of Physics, Vilnius, Lithuania, Institute of Botany, Academia Sinica, Taipei, Taiwan, ROC, and State Key Laboratory for Ultrafast Laser Spectroscopy, Zhongshan University, Quangzhou, PRC
| | - C. M. Yang
- Institute of Atomic and Molecular Sciences, Academia Sinica, Taipei, Taiwan, ROC, Department of Chemistry, National Taiwan University, Taipei, Taiwan, ROC, Center for Condensed Matter Sciences, National Taiwan University, Taipei, Taiwan, ROC, Institute of Physics, Vilnius, Lithuania, Institute of Botany, Academia Sinica, Taipei, Taiwan, ROC, and State Key Laboratory for Ultrafast Laser Spectroscopy, Zhongshan University, Quangzhou, PRC
| | - T.-S. Yang
- Institute of Atomic and Molecular Sciences, Academia Sinica, Taipei, Taiwan, ROC, Department of Chemistry, National Taiwan University, Taipei, Taiwan, ROC, Center for Condensed Matter Sciences, National Taiwan University, Taipei, Taiwan, ROC, Institute of Physics, Vilnius, Lithuania, Institute of Botany, Academia Sinica, Taipei, Taiwan, ROC, and State Key Laboratory for Ultrafast Laser Spectroscopy, Zhongshan University, Quangzhou, PRC
| | - H. Z. Wang
- Institute of Atomic and Molecular Sciences, Academia Sinica, Taipei, Taiwan, ROC, Department of Chemistry, National Taiwan University, Taipei, Taiwan, ROC, Center for Condensed Matter Sciences, National Taiwan University, Taipei, Taiwan, ROC, Institute of Physics, Vilnius, Lithuania, Institute of Botany, Academia Sinica, Taipei, Taiwan, ROC, and State Key Laboratory for Ultrafast Laser Spectroscopy, Zhongshan University, Quangzhou, PRC
| | - Yit-Tsong Chen
- Institute of Atomic and Molecular Sciences, Academia Sinica, Taipei, Taiwan, ROC, Department of Chemistry, National Taiwan University, Taipei, Taiwan, ROC, Center for Condensed Matter Sciences, National Taiwan University, Taipei, Taiwan, ROC, Institute of Physics, Vilnius, Lithuania, Institute of Botany, Academia Sinica, Taipei, Taiwan, ROC, and State Key Laboratory for Ultrafast Laser Spectroscopy, Zhongshan University, Quangzhou, PRC
| | - S. H. Lin
- Institute of Atomic and Molecular Sciences, Academia Sinica, Taipei, Taiwan, ROC, Department of Chemistry, National Taiwan University, Taipei, Taiwan, ROC, Center for Condensed Matter Sciences, National Taiwan University, Taipei, Taiwan, ROC, Institute of Physics, Vilnius, Lithuania, Institute of Botany, Academia Sinica, Taipei, Taiwan, ROC, and State Key Laboratory for Ultrafast Laser Spectroscopy, Zhongshan University, Quangzhou, PRC
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9
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Mroginski MA, Németh K, Magdó I, Müller M, Robben U, Della Védova C, Hildebrandt P, Mark F. Calculation of the Vibrational Spectra of Linear Tetrapyrroles. 2. Resonance Raman Spectra of Hexamethylpyrromethene Monomers. J Phys Chem B 2000. [DOI: 10.1021/jp000444h] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Maria-Andrea Mroginski
- Max-Planck-Institut für Strahlenchemie, Postfach 101365, D-45413 Mülheim a.d. Ruhr, Germany, and Departamento de Química, Facultad de Ciencias Exactas, Universidad Nacional de La Plata, 47 esq. 115, 1900 La Plata, Argentina
| | - Károly Németh
- Max-Planck-Institut für Strahlenchemie, Postfach 101365, D-45413 Mülheim a.d. Ruhr, Germany, and Departamento de Química, Facultad de Ciencias Exactas, Universidad Nacional de La Plata, 47 esq. 115, 1900 La Plata, Argentina
| | - Ildikó Magdó
- Max-Planck-Institut für Strahlenchemie, Postfach 101365, D-45413 Mülheim a.d. Ruhr, Germany, and Departamento de Química, Facultad de Ciencias Exactas, Universidad Nacional de La Plata, 47 esq. 115, 1900 La Plata, Argentina
| | - Martin Müller
- Max-Planck-Institut für Strahlenchemie, Postfach 101365, D-45413 Mülheim a.d. Ruhr, Germany, and Departamento de Química, Facultad de Ciencias Exactas, Universidad Nacional de La Plata, 47 esq. 115, 1900 La Plata, Argentina
| | - Uwe Robben
- Max-Planck-Institut für Strahlenchemie, Postfach 101365, D-45413 Mülheim a.d. Ruhr, Germany, and Departamento de Química, Facultad de Ciencias Exactas, Universidad Nacional de La Plata, 47 esq. 115, 1900 La Plata, Argentina
| | - Carlos Della Védova
- Max-Planck-Institut für Strahlenchemie, Postfach 101365, D-45413 Mülheim a.d. Ruhr, Germany, and Departamento de Química, Facultad de Ciencias Exactas, Universidad Nacional de La Plata, 47 esq. 115, 1900 La Plata, Argentina
| | - Peter Hildebrandt
- Max-Planck-Institut für Strahlenchemie, Postfach 101365, D-45413 Mülheim a.d. Ruhr, Germany, and Departamento de Química, Facultad de Ciencias Exactas, Universidad Nacional de La Plata, 47 esq. 115, 1900 La Plata, Argentina
| | - Franz Mark
- Max-Planck-Institut für Strahlenchemie, Postfach 101365, D-45413 Mülheim a.d. Ruhr, Germany, and Departamento de Química, Facultad de Ciencias Exactas, Universidad Nacional de La Plata, 47 esq. 115, 1900 La Plata, Argentina
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10
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Abstract
Laser technology has developed to the point where it is possible to utilize lasers as a sophisticated but accessible tool in understanding and manipulating gene functioning. This review emphasizes some of the systems that employ lasers in the new and growing field of molecular laser biotechnology. Here the main emphasis is on the manipulation and understanding of bacterial and plant systems.
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Affiliation(s)
- V P Grishko
- Department of Biology, University of Waterloo, Waterloo, ON N2L 3G1, Canada.
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11
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Schödel R, Irrgang KD, Voigt J, Renger G. Quenching of chlorophyll fluorescence by triplets in solubilized light-harvesting complex II (LHCII). Biophys J 1999; 76:2238-48. [PMID: 10096919 PMCID: PMC1300197 DOI: 10.1016/s0006-3495(99)77380-7] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
The quenching of chlorophyll fluorescence by triplets in solubilized trimeric light harvesting complexes was analyzed by comparative pump-probe experiments that monitor with weak 2-ns probe pulses the fluorescence yield and changes of optical density, DeltaOD, induced by 2-ns pump pulses. By using a special array for the measurement of the probe fluorescence (Schödel R., F. Hillman, T. Schrötter, K.-D. Irrgang, J. Voight, and G. Biophys. J. 71:3370-3380) the emission caused by the pump pulses could be drastically reduced so that even at highest pump pulse intensities, IP, no significant interference with the signal due to the probe pulse was observed. The data obtained reveal: a) at a fixed time delay of 50 ns between pump and probe pulse the fluorescence yield of the latter drastically decreased with increasing IP, b) the recovery of the fluorescence yield in the microseconds time domain exhibits kinetics which are dependent on IP, c) DeltaOD at 507 nm induced by the pump pulse and monitored by the probe pulse with a delay of 50 ns (reflecting carotenoid triplets) increases with IP without reaching a saturation level at highest IP values, d) an analogous feature is observed for the bleaching at 675 nm but it becomes significant only at very high IP values, e) the relaxation of DeltaOD at 507 nm occurs via a monophasic kinetics at all IP values whereas DeltaOD at 675 nm measured under the same conditions is characterized by a biphasic kinetics with tau values of about 1 microseconds and 7-9 microseconds. The latter corresponds with the monoexponential decay kinetics of DeltaOD at 507 nm. Based on a Stern-Volmer plot, the time-dependent fluorescence quenching is compared with the relaxation kinetics of triplets. It is shown that the fluorescence data can be consistently described by a quenching due to triplets.
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Affiliation(s)
- R Schödel
- AG Molekulare Biophysik und Spektroskopie, Institut für Physik der Humboldt Universität zu Berlin, Germany.
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12
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Magdó I, Németh K, Mark F, Hildebrandt P, Schaffner K. Calculation of Vibrational Spectra of Linear Tetrapyrroles. 1. Global Sets of Scaling Factors for Force Fields Derived by ab Initio and Density Functional Theory Methods. J Phys Chem A 1999. [DOI: 10.1021/jp983101g] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Ildikó Magdó
- Max-Planck-Institut für Strahlenchemie, Postfach 101365, D-45413 Mülheim an der Ruhr, Germany
| | - Károly Németh
- Max-Planck-Institut für Strahlenchemie, Postfach 101365, D-45413 Mülheim an der Ruhr, Germany
| | - Franz Mark
- Max-Planck-Institut für Strahlenchemie, Postfach 101365, D-45413 Mülheim an der Ruhr, Germany
| | - Peter Hildebrandt
- Max-Planck-Institut für Strahlenchemie, Postfach 101365, D-45413 Mülheim an der Ruhr, Germany
| | - Kurt Schaffner
- Max-Planck-Institut für Strahlenchemie, Postfach 101365, D-45413 Mülheim an der Ruhr, Germany
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Konermann L, Gatzen G, Holzwarth AR. Primary Processes and Structure of the Photosystem II Reaction Center. 5. Modeling of the Fluorescence Kinetics of the D1−D2−cyt-b559 Complex at 77 K. J Phys Chem B 1997. [DOI: 10.1021/jp9606671] [Citation(s) in RCA: 45] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Lars Konermann
- Max-Planck-Institut für Strahlenchemie, Stiftstrasse 34-36, D-45470 Mülheim a.d. Ruhr, Germany
| | - Guido Gatzen
- Max-Planck-Institut für Strahlenchemie, Stiftstrasse 34-36, D-45470 Mülheim a.d. Ruhr, Germany
| | - Alfred R. Holzwarth
- Max-Planck-Institut für Strahlenchemie, Stiftstrasse 34-36, D-45470 Mülheim a.d. Ruhr, Germany
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Schödel R, Hillmann F, Schrötter T, Voigt J, Irrgang KD, Renger G. Kinetics of excited states of pigment clusters in solubilized light-harvesting complex II: photon density-dependent fluorescence yield and transmittance. Biophys J 1996; 71:3370-80. [PMID: 8968606 PMCID: PMC1233824 DOI: 10.1016/s0006-3495(96)79530-9] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
Relative fluorescence yield, phi F, and transmittance, T, were measured in solubilized light-harvesting complex II (LHCII) as a function of photon density, Ip, of monochromatic 645-nm laser pulses (duration: approximately 2.5 ns). Special efforts were made in constructing an optical set-up that allows the accurate determination of the fluorescence from an area of constant Ip, phi F(Ip) starts to decline at approximately 10(14) and drops to values below 0.01% at maximum Ip (approximately 10(19) photons cm-2 pulse-1). T(Ip) decreases only slightly at photon densities of approximately 10(15) but increases steeply at values of > 10(17) photons cm-2 pulse-1. The interpretation of the phi F(Ip) data using the saturation limit of Mauzerall's multiple hit model leads to a unit size of about 10-15 chlorophyll molecules. One interpretation is to attribute this result to a very fast exciton-exciton annihilation of multiple excited states generated within this small domain. Alternatively, based on the assumption that delocalized cluster states within the monomeric/trimeric subunit of LHCII exist, the results can be consistently described by a kinetic model comprising ground, monoexcitonic, and biexcitonic states of clusters and a triplet state that is quenched by carotenoids in LHCII. Within the framework of this model the annihilation of multiple excitations is explained as ultrafast radiationless relaxation of higher excited cluster states. Comparative measurements in diluted acetonic Chl a solution are consistently described by the depletion of the ground state, taking the absorption cross section at the used wavelength.
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Affiliation(s)
- R Schödel
- AG Molekulare Biophysik und Spektroskopie, Humboldt Universität zu Berlin, Germany.
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15
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White NTH, Beddard GS, Thorne JRG, Feehan TM, Keyes TE, Heathcote P. Primary Charge Separation and Energy Transfer in the Photosystem I Reaction Center of Higher Plants. ACTA ACUST UNITED AC 1996. [DOI: 10.1021/jp9604709] [Citation(s) in RCA: 41] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Nigel T. H. White
- Department of Chemistry, University of Manchester, Manchester M13 9PL, U.K., and School of Biological Sciences, Queen Mary and Westfield College, Mile End Road, London E1 4NS, U.K
| | - Godfrey S. Beddard
- Department of Chemistry, University of Manchester, Manchester M13 9PL, U.K., and School of Biological Sciences, Queen Mary and Westfield College, Mile End Road, London E1 4NS, U.K
| | - Jonathan R. G. Thorne
- Department of Chemistry, University of Manchester, Manchester M13 9PL, U.K., and School of Biological Sciences, Queen Mary and Westfield College, Mile End Road, London E1 4NS, U.K
| | - Tim M. Feehan
- Department of Chemistry, University of Manchester, Manchester M13 9PL, U.K., and School of Biological Sciences, Queen Mary and Westfield College, Mile End Road, London E1 4NS, U.K
| | - Tia E. Keyes
- Department of Chemistry, University of Manchester, Manchester M13 9PL, U.K., and School of Biological Sciences, Queen Mary and Westfield College, Mile End Road, London E1 4NS, U.K
| | - Peter Heathcote
- Department of Chemistry, University of Manchester, Manchester M13 9PL, U.K., and School of Biological Sciences, Queen Mary and Westfield College, Mile End Road, London E1 4NS, U.K
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Edington MD, Riter RE, Beck WF. Interexciton-State Relaxation and Exciton Localization in Allophycocyanin Trimers. ACTA ACUST UNITED AC 1996. [DOI: 10.1021/jp960454b] [Citation(s) in RCA: 51] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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18
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Exciton equilibration in the light-harvesting complex of Photosystem II of higher plants. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 1995. [DOI: 10.1016/0005-2728(95)00063-o] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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Affiliation(s)
- A R Holzwarth
- Max-Planck-Institut for Radiation Chemistry, Mülheim/Ruhr, Germany
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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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Laible PD, Zipfel W, Owens TG. Excited state dynamics in chlorophyll-based antennae: the role of transfer equilibrium. Biophys J 1994; 66:844-60. [PMID: 8011917 PMCID: PMC1275783 DOI: 10.1016/s0006-3495(94)80861-6] [Citation(s) in RCA: 63] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Abstract
We present computer simulations of excited state dynamics in models of PS I and PS II which are based upon known structural and spectral properties of the antennae. In particular, these models constrain the pigment binding sites to three-dimensional volumes determined from molecular properties of the antenna complexes. The simulations demonstrate that within a 10-30 ps after light absorption, rapid energy transfer among coupled antenna chlorophylls leads to a quasiequilibrium state in which the fraction of the excited state on any antenna chlorophyll, normalized to the total excited state remaining on the model, remains constant with time. We describe this quasiequilibrium state as a "transfer equilibrium" (TE) state because of its dependence on the rates of processes that couple excited state motion and quenching in the antenna as well as on the individual antenna site energies and temperature. The TE state is not a true equilibrium in that loss of the excited state primarily due to photochemistry (but also due to fluorescence, thermal emission, and intersystem crossing) continues once TE is established. Depending on the dynamics of the system, the normalized distribution of excited state at TE may differ substantially from the Boltzmann distribution (the state of the model at infinite time in the absence of any avenues for decay of excited state). The models predict lifetimes, equilibration times, and photochemical yields that are in agreement with experimental data and affirm trap-limited dynamics in both photosystems. The rapid occurrence of TE states implies that any excited state dynamics that depends on antenna structure and excitation wavelength must occur before the TE state is established. We demonstrate that the excited state distribution of the TE state is central to determining the excited state lifetime and quantum efficiency of photochemistry.
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Affiliation(s)
- P D Laible
- Section of Plant Biology, Cornell University, Ithaca, New York 14853-5908
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Abstract
Chloroplasts contain a system of membrane sacs, the thylakoids, some of which are stacked to form grana (singular, granum), whereas others float freely in the stroma. It is on the thylakoid membranes that the electron carriers necessary for photosynthesis reside. There has been continuous speculation and discussion about the function of the grana ever since Menke postulated their lamellar nature in 1939. On the basis of new insights into the biophysics of the two photosystems and the molecular organization of thylakoid membranes of algae that exhibit a different lateral heterogeneity from that of higher plants, we propose that the membrane stacking found in the chloroplasts of higher plants and green algae is just one way in which Nature implements a general principle, namely that of physically separating a slow (PS II) and a fast (PS I) photosystem.
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Affiliation(s)
- H W Trissl
- Abteilung Biophysik, Universität Osnabrück, Germany
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23
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Photoelectrochemistry of thylakoid and sub-thylakoid membrane preparations: Cyclic voltammetry and action spectra. Electrochim Acta 1993. [DOI: 10.1016/0013-4686(93)85030-3] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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24
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Lippitsch ME, Hermann G, Brunner H, Müller E, Aussenegg FR. Picosecond events in the phototransformation of phytochrome — a time-resolved absorption study. JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY B-BIOLOGY 1993. [DOI: 10.1016/1011-1344(93)80036-9] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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25
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Hucke M, Schweitzer G, Holzwarth AR, Sidler W, Zuber H. STUDIES ON CHROMOPHORE COUPLING IN ISOLATED PHYCOBILIPROTEINS. IV. FEMTOSECOND TRANSIENT ABSORPTION STUDY OF ULTRAFAST EXCITED STATE DYNAMICS IN TRIMERIC PHYCOERYTHROCYANIN COMPLEXES. Photochem Photobiol 1993. [DOI: 10.1111/j.1751-1097.1993.tb02258.x] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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26
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Bittner TH, Voigt J, Irrgang KD, Renger G. NONLINEAR LASERSPECTROSCOPIC INVESTIGATIONS OF THE PIGMENT-PIGMENT INTERACTION WITHIN THE LIGHT-HARVESTING COMPLEX OF PHOTOSYSTEM II. Photochem Photobiol 1993. [DOI: 10.1111/j.1751-1097.1993.tb02272.x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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27
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Gillbro T, Sharkov AV, Kryukov IV, Khoroshilov EV, Kryukov PG, Fischer R, Scheer H. Förster energy transfer between neighbouring chromophores in C-phycocyanin trimers. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 1993. [DOI: 10.1016/0005-2728(93)90072-n] [Citation(s) in RCA: 46] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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28
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The phototransformation process in phytochrome. I. Ultrafast fluorescence component and kinetic models for the initial Pr → Pfr transformation steps in native phytochrome. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 1992. [DOI: 10.1016/0005-2728(92)90020-3] [Citation(s) in RCA: 47] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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29
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Freiberg A, Timpmann K. Picosecond fluorescence spectroscope of light-harvesting antenna complexes from Rhodospirillum rubrum in the 300-4 K temperature range. Comparison with the data on chromatophores. JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY B-BIOLOGY 1992. [DOI: 10.1016/1011-1344(92)87012-x] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
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30
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Jia Y, Jean JM, Werst MM, Chan CK, Fleming GR. Simulations of the temperature dependence of energy transfer in the PSI core antenna. Biophys J 1992; 63:259-73. [PMID: 1420871 PMCID: PMC1262143 DOI: 10.1016/s0006-3495(92)81589-8] [Citation(s) in RCA: 66] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
In order to understand the organization of the PSI core antenna and to interpret results obtained from studies of the temperature and wavelength dependence of energy transfer and trapping in the PSI particles, we have constructed a model for PSI in which spectral heterogeneity is considered via a self-consistent approach based on Forster transport. The temperature dependence of the absorption and emission spectra of the individual Chl molecules in the protein matrix is calculated based on a model Hamiltonian which includes a phonon contribution. Time and wavelength resolved kinetics of PSI at different temperatures are investigated by means of two-dimensional lattice models. We conclude that wavelength-dependent fluorescence decay kinetics result only when two or more bottlenecks exist in the energy transfer and trapping process. A single trap or several pseudo-traps with spectrally identical environments do not lead to wavelength dependent decays. Simple funnel arrangements of the spectral types can be ruled out. At least one pigment with energy lower than the photochemical trap located close to the reaction center is required to produce the trends of the fluorescence lifetimes observed experimentally. The remainder of the core antenna is consistent with a random arrangement of spectral types.
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Affiliation(s)
- Y Jia
- Department of Chemistry, University of Chicago, Illinois 60637
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31
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Chlorosomes, photosynthetic antennae with novel self-organized pigment structures. J Photochem Photobiol A Chem 1992. [DOI: 10.1016/1010-6030(92)85032-p] [Citation(s) in RCA: 83] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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32
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Werst M, Jia Y, Mets L, Fleming GR. Energy transfer and trapping in the photosystem I core antenna. A temperature study. Biophys J 1992; 61:868-78. [PMID: 1581501 PMCID: PMC1260346 DOI: 10.1016/s0006-3495(92)81894-5] [Citation(s) in RCA: 62] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
The fluorescence decay kinetics of the photosystem I-only mutant strain of Chlamydomonas reinhardtii, A4d, are used to study energy transfer and structural organization in photosystem I (PSI). Time-resolved measurements over a wide temperature range (36-295 K) have been made both on cells containing approximately 65 core chl a/P700 and an additional 60-70 chl a + b from LHC proteins and on PSI particles containing 40-50 chl a/P700. In each case, the fluorescence decay kinetics is dominated by a short component, tau 1 which is largely attributed to the lifetime of the excitations in the core complex. The results are discussed in terms of simulations of the temperature dependence of tau 1 in model systems. Spectral inhomogeneity and the temperature dependence of the spectral lineshapes are included explicitly in the simulations. Various kinds of antenna arrangements are modeled with and without the inclusion of pigments with lower absorption energies than the trap (red pigments). We conclude that funnel arrangements are not consistent with our measurements. A random model that includes one or two red pigments placed close to the trap shows temperature and wavelength dependence similar to that observed experimentally. A comparison of the temperature dependence of tau 1 for cells and PSI particles is included.
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Affiliation(s)
- M Werst
- Department of Chemistry, University of Chicago, Illinois 60637
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33
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Reddy NR, Lyle PA, Small GJ. Applications of spectral hole burning spectroscopies to antenna and reaction center complexes. PHOTOSYNTHESIS RESEARCH 1992; 31:167-194. [PMID: 24408059 DOI: 10.1007/bf00035536] [Citation(s) in RCA: 82] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/18/1991] [Accepted: 09/27/1991] [Indexed: 06/03/2023]
Abstract
The underlying principles of spectral hole burning spectroscopies and the theory for hole profiles are reviewed and illustrated with calculated spectra. The methodology by which the dependence of the overall hole profile on burn wavelength can be used to reveal the contributions from site inhomogeneous broadening and various homogeneous broadening contributions to the broad Qy-absorption bands of cofactors is emphasized. Applications to the primary electron donor states of the reaction centers of purple bacteria and Photosystems I and II of green plants are discussed. The antenna (light harvesting) complexes considered include B800-B850 and B875 of Rhodobacter sphaeroides and the base-plate complex of Prosthecochloris aestuarii with particular attention being given to excitonic interactions and level structure. The data presented show that spectral hole burning is a generally applicable low temperature approach for the study of excited state electronic and vibrational (intramolecular, phonon) structures, structural heterogeneity and excited state lifetimes.
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Affiliation(s)
- N R Reddy
- Ames Laboratory-USDOE, Iowa State University, 50011, Ames, IA, USA
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34
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Müller MG, Griebenow K, Holzwarth AR. Primary processes in isolated photosynthetic bacterial reaction centres from Chloroflexus aurantiacus studied by picosecond fluorescence spectroscopy. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 1991. [DOI: 10.1016/0005-2728(91)90002-6] [Citation(s) in RCA: 51] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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35
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Booth PJ, Crystall B, Ahmad I, Barber J, Porter G, Klug DR. Observation of multiple radical pair states in photosystem 2 reaction centers. Biochemistry 1991; 30:7573-86. [PMID: 1854756 DOI: 10.1021/bi00244a029] [Citation(s) in RCA: 65] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Charge recombination of the primary radical pair in D1/D2 reaction centers from photosystem 2 has been studied by time-resolved fluorescence and absorption spectroscopy. The kinetics of the primary radical pair are multiexponential and exhibit at least two lifetimes of 20 and 52 ns. In addition, a third lifetime of approximately 500 ps also appears to be present. These multiexponential charge-recombination kinetics reflect either different conformational states of D1/D2 reaction centers, with the different conformers exhibiting different radical pair lifetimes, or relaxations in the free energy of the radical pair state. Whichever model is invoked, the free energies of formation of the different radical pair states exhibit a linear temperature dependence from 100 to 220 K, indicating that they are dominated by entropy with negligible enthalpy contributions. These results are in agreement with previous determinations of the thermodynamics that govern primary charge separation in both D1/D2 reaction centers [Booth, P.J., Crystall, B., Giorgi, L. B., Barber, J., Klug, D.R., & Porter, G. (1990) Biochim. Biophys. Acta 1016, 141-152] and reaction centers of purple bacteria [Woodbury, N.W.T., & Parson, W.W. (1984) Biochim. Biophys. Acta 767, 345-361]. It is possible that these observations reflect structural changes that accompanying primary charge separation and assist in stabilization of the radical pair state thus optimizing the efficiency of primary electron transfer.
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Affiliation(s)
- P J Booth
- Photochemistry Research Group, Department of Biology, Imperial College, London, U.K
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36
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Lee J, Wang YY, Gibson BG. Electronic excitation transfer in the complex of lumazine protein with bacterial bioluminescence intermediates. Biochemistry 1991; 30:6825-35. [PMID: 2069948 DOI: 10.1021/bi00242a004] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Fluorescence dynamics measurements have been made on the bioluminescence reaction intermediates using Photobacterium leiognathi, Vibrio fischeri, and Vibrio harveyi luciferases, both alone and in mixtures with Photobacterium phosphoreum lumazine protein. Each luciferase produces a "fluorescent transient" intermediate on reaction with the bioluminescence substrates, FMNH2, tetradecanal, and O2, and all have a fluorescence quantum yield about 0.3, with a predominant lifetime around 10 ns. The P. leiognathi luciferase fluorescent transient has a rotational correlation time of 79 ns at 2 degrees C, as expected for the rotational diffusion of a 77-kDa macromolecule. In the presence of lumazine protein however a faster correlation time of about 3 ns predominates. This rapid channel of anisotropy loss is attributed to energy transfer from the flavin intermediate bound on the luciferase to the lumazine ligand, reflects the presence of protein-protein complexation, and is greatest in the case of P. leiognathi, but not at all for V. fischeri. This fact is consistent with the strong influence of lumazine protein on the bioluminescence reaction of P. leiognathi, and not at all with V. fischeri. The rate of energy transfer is of order 10(9) s-1, much greater than the 10(8) s-1 fluorescence rate of the donor. Thus the bioluminescence excitation of lumazine protein could occur by a similar photophysical mechanism of interprotein energy transfer from a chemically excited fluorescent transient donor to the lumazine acceptor.
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Affiliation(s)
- J Lee
- Department of Biochemistry, University of Georgia, Athens 30602
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37
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Abstract
Picosecond infrared spectroscopy is developed and used for the first time to study the dynamics of photoexcited bacteriorhodopsin (BR). Both spectral and time-resolved data are obtained. The results open an entirely new approach to investigations of the BR photocycle. The infrared difference spectrum (K minus BR570) recorded at ambient temperature between 1,560 and 1,700 cm-1 is not identical with the spectrum reported for a frozen sample. Three bands of the K state at 1,622, 1,610, and 1,580 cm-1 and the bleaching at 1,637 cm-1 (C = NH stretch) are seen. These new spectral lines appear in less than 10 ps.
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Affiliation(s)
- R Diller
- Department of Chemistry, University of Pennsylvania, Philadelphia 19104
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38
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Energy transfer dynamics of the B800—B850 antenna complex of Rhodobacter sphaeroides: a hole burning study. Chem Phys Lett 1991. [DOI: 10.1016/0009-2614(91)90369-k] [Citation(s) in RCA: 102] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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39
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Bittner T, Voigt J, Kehrberg G, Eckert HJ, Renger G. Evidence of excited state absorption in PS II membrane fragments. PHOTOSYNTHESIS RESEARCH 1991; 28:131-139. [PMID: 24414972 DOI: 10.1007/bf00054126] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/19/1990] [Accepted: 05/04/1991] [Indexed: 06/03/2023]
Abstract
Utilizing a two-beam technique in the frequency domain, the pumped absorption of PS II membrane fragments from spinach and of acetonic chlorophyll-a solutions was measured at room temperature. In a very narrow wavelength region (0.2 nm around the pump pulse wavelength) the relative test beam transmission exhibited either a decrease or an increase, respectively, dependent on the intensity of a strong pump beam. In contrast, the transmission changes of chl-a solutions were not affected by the wavelength mistuning between pump and test beam. The data obtained for PS II membrane fragments were interpreted in terms of excited state absorption of pigment-protein clusters within the light-harvesting complex of PS II. The interpretation of the small absorption band as a homogeneously broadened line led to a transversal relaxation time for chlorophyll in vivo of about 1 ps.
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Affiliation(s)
- T Bittner
- Fachbereich Physik, Institut für Optik und Spektroskopie, Humboldt Universität, Invalidenstr. 42, 1040, Berlin, Germany
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40
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Renger G, Rettig W, Gräber P. The effect of UVB irradiation on the lifetimes of singlet excitons in isolated photosystem II membrane fragments from spinach. JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY B-BIOLOGY 1991. [DOI: 10.1016/1011-1344(91)80152-8] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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41
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Miller M, Cox RP, Gillbro T. Energy transfer kinetics in chlorosomes from Chloroflexus aurantiacus: studies using picosecond absorbance spectroscopy. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 1991. [DOI: 10.1016/s0005-2728(05)80101-x] [Citation(s) in RCA: 25] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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42
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Lakowicz JR, Kuśba J, Wiczk W, Gryczynski I, Szmacinski H, Johnson ML. Resolution of the conformational distribution and dynamics of a flexible molecule using frequency-domain fluorometry. Biophys Chem 1991; 39:79-84. [PMID: 2012836 DOI: 10.1016/0301-4622(91)85008-e] [Citation(s) in RCA: 29] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
We report the first resolution of both the conformational distribution and end-to-end diffusion coefficient of a flexible molecule. This molecular information was recovered using only the donor intensity decay in a single solvent at a single viscosity, as observed by the technique of frequency-domain fluorometry. This technique can be extended to measurements of structural fluctuations of biological macromolecules.
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Affiliation(s)
- J R Lakowicz
- University of Maryland, School of Medicine, Department of Biological Chemistry, Baltimore 21201
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44
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Lakowicz JR, Kuśba J, Wiczk W, Gryczynski I, Johnson ML. End-to-end diffusion of a flexible bichromophoric molecule observed by intramolecular energy transfer and frequency-domain fluorometry. Chem Phys Lett 1990. [DOI: 10.1016/0009-2614(90)85277-j] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
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45
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Mimuro M. Studies on excitation energy flow in the photosynthetic pigment system; Structure and energy transfer mechanism. ACTA ACUST UNITED AC 1990. [DOI: 10.1007/bf02489628] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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46
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