1
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Šímová I, Kuznetsova V, Gardiner AT, Šebelík V, Koblížek M, Fuciman M, Polívka T. Carotenoid responds to excess energy dissipation in the LH2 complex from Rhodoblastus acidophilus. PHOTOSYNTHESIS RESEARCH 2022; 154:75-87. [PMID: 36066816 DOI: 10.1007/s11120-022-00952-5] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/22/2022] [Accepted: 08/17/2022] [Indexed: 06/15/2023]
Abstract
The functions of both (bacterio) chlorophylls and carotenoids in light-harvesting complexes have been extensively studied during the past decade, yet, the involvement of BChl a high-energy Soret band in the cascade of light-harvesting processes still remains a relatively unexplored topic. Here, we present transient absorption data recorded after excitation of the Soret band in the LH2 complex from Rhodoblastus acidophilus. Comparison of obtained data to those recorded after excitation of rhodopin glucoside and B800 BChl a suggests that no Soret-to-Car energy transfer pathway is active in LH2 complex. Furthermore, a spectrally rich pattern observed in the spectral region of rhodopin glucoside ground state bleaching (420-550 nm) has been assigned to an electrochromic shift. The results of global fitting analysis demonstrate two more features. A 6 ps component obtained exclusively after excitation of the Soret band has been assigned to the response of rhodopin glucoside to excess energy dissipation in LH2. Another time component, ~ 450 ps, appearing independently of the excitation wavelength was assigned to BChl a-to-Car triplet-triplet transfer. Presented data demonstrate several new features of LH2 complex and its behavior following the excitation of the Soret band.
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Affiliation(s)
- Ivana Šímová
- Department of Physics, Faculty of Science, University of South Bohemia, Branišovská, 1760, 370 05, Ceske Budejovice, Czech Republic
| | - Valentyna Kuznetsova
- Department of Physics, Faculty of Science, University of South Bohemia, Branišovská, 1760, 370 05, Ceske Budejovice, Czech Republic
| | - Alastair T Gardiner
- Laboratory of Anoxygenic Phototrophs, Institute of Microbiology, Czech Academy of Sciences, 379 81, Třeboň, Czech Republic
| | - Václav Šebelík
- Department of Physics, Faculty of Science, University of South Bohemia, Branišovská, 1760, 370 05, Ceske Budejovice, Czech Republic
- Dynamical Spectroscopy, Department of Chemistry, Technical University of Munich, Lichtenbergstraße 4, 85748, Garching b. Munich, Germany
| | - Michal Koblížek
- Laboratory of Anoxygenic Phototrophs, Institute of Microbiology, Czech Academy of Sciences, 379 81, Třeboň, Czech Republic
| | - Marcel Fuciman
- Department of Physics, Faculty of Science, University of South Bohemia, Branišovská, 1760, 370 05, Ceske Budejovice, Czech Republic
| | - Tomáš Polívka
- Department of Physics, Faculty of Science, University of South Bohemia, Branišovská, 1760, 370 05, Ceske Budejovice, Czech Republic.
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2
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Šebelík V, Duffy CDP, Keil E, Polívka T, Hauer J. Understanding Carotenoid Dynamics via the Vibronic Energy Relaxation Approach. J Phys Chem B 2022; 126:3985-3994. [PMID: 35609122 DOI: 10.1021/acs.jpcb.2c00996] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Carotenoids are an integral part of natural photosynthetic complexes, with tasks ranging from light harvesting to photoprotection. Their underlying energy deactivation network of optically dark and bright excited states is extremely efficient: after excitation of light with up to 2.5 eV of photon energy, the system relaxes back to ground state on a time scale of a few picoseconds. In this article, we summarize how a model based on the vibrational energy relaxation approach (VERA) explains the main characteristics of relaxation dynamics after one-photon excitation with special emphasis on the so-called S* state. Lineshapes after two-photon excitation are beyond the current model of VERA. We outline this future line of research in our article. In terms of experimental method development, we discuss which techniques are needed to better describe energy dissipation effects in carotenoids and within the first solvation shell.
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Affiliation(s)
- Václav Šebelík
- Dynamical Spectroscopy, Department of Chemistry, Technical University of Munich, Lichtenbergstraße 4, 85748 Garching bei Munich, Germany
| | - Christopher D P Duffy
- Digital Environment Research Institute, Queen Mary University of London, London E1 4NS, U.K
| | - Erika Keil
- Dynamical Spectroscopy, Department of Chemistry, Technical University of Munich, Lichtenbergstraße 4, 85748 Garching bei Munich, Germany
| | - Tomáš Polívka
- Department of Physics, Faculty of Science, University of South Bohemia, Branišovská 1760, 370 05 České Budějovice, Czech Republic.,Biology Centre, Institute of Plant Molecular Biology, Czech Academy of Sciences, Branišovská 1160/31, 370 05 České Budějovice, Czech Republic
| | - Jürgen Hauer
- Dynamical Spectroscopy, Department of Chemistry, Technical University of Munich, Lichtenbergstraße 4, 85748 Garching bei Munich, Germany
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3
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Investigating carotenoid photophysics in photosynthesis with 2D electronic spectroscopy. TRENDS IN CHEMISTRY 2021. [DOI: 10.1016/j.trechm.2021.05.008] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
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4
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The role of carotenoids in proton-pumping rhodopsin as a primitive solar energy conversion system. JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY B-BIOLOGY 2021; 221:112241. [PMID: 34130090 DOI: 10.1016/j.jphotobiol.2021.112241] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/27/2021] [Revised: 06/02/2021] [Accepted: 06/06/2021] [Indexed: 12/24/2022]
Abstract
Rhodopsin and carotenoids are two molecules that certain bacteria use to absorb and utilize light. Type I rhodopsin, the simplest active proton transporter, converts light energy into an electrochemical potential. Light produces a proton gradient, which is known as the proton motive force across the cell membrane. Some carotenoids are involved in light absorbance and transfer of absorbed energy to chlorophyll during photosynthesis. A previous study in Salinibacter ruber has shown that carotenoids act as antennae to harvest light and transfer energy to retinal in xanthorhodopsin (XR). Here, we describe the role of canthaxanthin (CAN), a carotenoid, as an antenna for Gloeobacter rhodopsin (GR). The non-covalent complex formed by the interaction between CAN and GR doubled the proton pumping speed and improved the pumping capacity by 1.5-fold. The complex also tripled the proton pumping speed and improved the pumping capacity by 5-fold in the presence of strong and weak light, respectively. Interestingly, when canthaxanthin was bound to Gloeobacter rhodopsin, it showed a 126-fold increase in heat resistance, and it survived better under drought conditions than Gloeobacter rhodopsin. The results suggest direct complementation of Gloeobacter rhodopsin with a carotenoid for primitive solar energy harvesting in cyanobacteria.
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5
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Gacek DA, Betke A, Nowak J, Lokstein H, Walla PJ. Two-photon absorption and excitation spectroscopy of carotenoids, chlorophylls and pigment-protein complexes. Phys Chem Chem Phys 2021; 23:8731-8738. [PMID: 33876032 DOI: 10.1039/d1cp00656h] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
In addition to (bacterio)chlorophylls, (B)Chls, photosynthetic pigment-protein complexes bind carotenoids (Cars) that fulfil various important functions which are not fully understood, yet. However, certain excited states of Cars are optically one-photon forbidden ("dark") and can potentially undergo excitation energy transfer (EET) to (B)Chls following two-photon absorption (TPA). The amount of EET is reflected by the differences in TPA and two-photon excitation (TPE) spectra of a complex (multi-pigment) system. Since it is technically and analytically demanding to resolve optically forbidden states, different studies reported varying contributions of Cars and Chls to TPE/TPA spectra. In a study using well-defined 1 : 1 Car-tetrapyrrole dyads TPE contributions of tetrapyrrole molecules, including Chls, and Cars were measured. In these experiments, TPE of Cars dominated over Chl a TPE in a broad wavelength range. Another study suggested only minor contributions of Cars to TPE spectra of pigment-protein complexes such as the plant main light-harvesting complex (LHCII), in particular for wavelengths longer than ∼600/1200 nm. By joining forces and a combined analysis of all available data by both teams, we try to resolve this apparent contradiction. Here, we demonstrate that reconstruction of a wide spectral range of TPE for LHCII and photosystem I (PSI) requires both, significant Car and Chl contributions. Direct comparison of TPE spectra obtained in both studies demonstrates a good agreement of the primary data. We conclude that in TPE spectra of LHCII and PSI, the contribution of Chls is dominating above 600/1200 nm, whereas the contributions of forbidden Car states increase particularly at wavelengths shorter than 600/1200 nm. Estimates of Car contributions to TPA as well as TPE spectra are given for various wavelengths.
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Affiliation(s)
- Daniel A Gacek
- Technische Universität Braunschweig, Institute for Physical and Theoretical Chemistry, Department for Biophysical Chemistry, Gaußstr. 17, 38106 Braunschweig, Germany.
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6
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Kundu A, Dasgupta J. Photogeneration of Long-Lived Triplet States through Singlet Fission in Lycopene H-Aggregates. J Phys Chem Lett 2021; 12:1468-1474. [PMID: 33528257 DOI: 10.1021/acs.jpclett.0c03301] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Molecular triplet excitons produced through singlet fission (SF) usually have shorter triplet lifetimes due to exciton-exciton recombination and relaxation pathways, thereby resulting in complex device architectures for SF-boosted solar cells. Using broadband transient absorption spectroscopy, we here show that the photoexcitation of nanostructured lycopene H-aggregates at room temperature produces free triplets with an unprecedented 35-fold enhancement in the lifetime compared to those localized on the monomer backbone. The observed rise of a spectrally blue-shifted correlated T-T pair state in ∼19 ps with distinct vibronic features provides the basis for SF-induced triplet generation.
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Affiliation(s)
- Arup Kundu
- Department of Chemical Sciences, Tata Institute of Fundamental Research, 1 Homi Bhabha Road, Mumbai 400005, India
| | - Jyotishman Dasgupta
- Department of Chemical Sciences, Tata Institute of Fundamental Research, 1 Homi Bhabha Road, Mumbai 400005, India
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7
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Kozlov MI, Poddubnyy VV. Electron-Vibrational Spectra and Dynamics of the Lutein Molecule. J Phys Chem B 2020; 124:5780-5787. [PMID: 32573243 DOI: 10.1021/acs.jpcb.0c02511] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The carotenoid molecules such as lutein play an important role in the absorption of light and the following transfer of energy during photosynthesis. However, the study of these processes by the experimental methods only is quite difficult because some of the transitions between the electronic states of carotenoids are optically forbidden and the effect of vibrational states change also must be taken into account. In the present work, electronic-vibrational states of the lutein molecule in the LHCII complex of higher plants and in the diethyl ether solution were described using the ab initio methods. For lutein of LHCII, the electronic energy transfer processes were modeled. The role of the "hot" S1 states of lutein was shown to be of great importance.
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Affiliation(s)
- Maxim I Kozlov
- Chemistry Department, Lomonosov Moscow State University, 119991 Moscow, Russia
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8
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Kollenz P, Herten DP, Buckup T. Unravelling the Kinetic Model of Photochemical Reactions via Deep Learning. J Phys Chem B 2020; 124:6358-6368. [PMID: 32589422 DOI: 10.1021/acs.jpcb.0c04299] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Time-resolved spectroscopies have been playing an essential role in the elucidation of the fundamental mechanisms of light-driven processes, particularly in exploring relaxation models for electronically excited molecules. However, the determination of such models from experimentally obtained time-resolved and spectrally resolved data still demands a high degree of intuition, frequently poses numerical challenges, and is often not free from ambiguities. Here, we demonstrate the analysis of time-resolved laser spectroscopy data via a deep learning network to obtain the correct relaxation kinetic model. In its current design, the presented Deep Spectroscopy Kinetic Analysis Network (DeepSKAN) can predict kinetic models (involved states and relaxation pathways) consisting of up to five states, which results in 103 possible different classes, by estimating the probability of occurrence of a given kinetic model class. DeepSKAN was trained with synthetic time-resolved spectra spanning over 4 orders of magnitude in time with a unitless time axis, thereby demonstrating its potential as a universal approach for analyzing data from various time-resolved spectroscopy techniques in different time ranges. By adding the probabilities of each pathway of the top-k models normalized by the total probability, we can determine the relaxation pathways for a given data set with high certainty (up to 99%). Due to its architecture and training, DeepSKAN is robust against experimental noise and typical preanalysis errors like time-zero corrections. Application of DeepSKAN to experimental data is successfully demonstrated for three different photoinduced processes: transient absorption of the retinal isomerization, transient IR spectroscopy of the relaxation of the photoactivated DRONPA, and transient absorption of the dynamics in lycopene. This approach delivers kinetic models and could be a unifying asset in several areas of spectroscopy.
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Affiliation(s)
- Philipp Kollenz
- Physikalisch Chemisches Institut, Ruprecht-Karls University, D-69120 Heidelberg, Germany
| | - Dirk-Peter Herten
- Physikalisch Chemisches Institut, Ruprecht-Karls University, D-69120 Heidelberg, Germany.,Institute of Cardiovascular Sciences & School of Chemistry, College of Medical and Dental Sciences, University of Birmingham, Edgbaston, B152TT, Birmingham, United Kingdom.,Centre of Membrane Proteins and Receptors (COMPARE), Universities of Birmingham and Nottingham, Midlands, United Kingdom
| | - Tiago Buckup
- Physikalisch Chemisches Institut, Ruprecht-Karls University, D-69120 Heidelberg, Germany
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9
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Niedzwiedzki DM, Swainsbury DJK, Hunter CN. Carotenoid-to-(bacterio)chlorophyll energy transfer in LH2 antenna complexes from Rba. sphaeroides reconstituted with non-native (bacterio)chlorophylls. PHOTOSYNTHESIS RESEARCH 2020; 144:155-169. [PMID: 31350671 PMCID: PMC7203092 DOI: 10.1007/s11120-019-00661-6] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/14/2019] [Accepted: 07/16/2019] [Indexed: 05/04/2023]
Abstract
Six variants of the LH2 antenna complex from Rba. sphaeroides, comprising the native B800-B850, B800-free LH2 (B850) and four LH2s with various (bacterio)chlorophylls reconstituted into the B800 site, have been investigated with static and time-resolved optical spectroscopies at room temperature and at 77 K. The study particularly focused on how reconstitution of a non-native (bacterio)chlorophylls affects excitation energy transfer between the naturally bound carotenoid spheroidene and artificially substituted pigments in the B800 site. Results demonstrate there is no apparent trend in the overall energy transfer rate from spheroidene to B850 bacteriochlorophyll a; however, a trend in energy transfer rate from the spheroidene S1 state to Qy of the B800 (bacterio)chlorophylls is noticeable. These outcomes were applied to test the validity of previously proposed energy values of the spheroidene S1 state, supporting a value in the vicinity of 13,400 cm-1 (746 nm).
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Affiliation(s)
- Dariusz M Niedzwiedzki
- Center for Solar Energy and Energy Storage, Washington University, St. Louis, MO, 63130, USA.
- Department of Energy, Environmental & Chemical Engineering, Washington University, St. Louis, MO, 63130, USA.
| | - David J K Swainsbury
- Department of Molecular Biology and Biotechnology, University of Sheffield, Sheffield, S10 2TN, UK
| | - C Neil Hunter
- Department of Molecular Biology and Biotechnology, University of Sheffield, Sheffield, S10 2TN, UK
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10
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A photosynthetic antenna complex foregoes unity carotenoid-to-bacteriochlorophyll energy transfer efficiency to ensure photoprotection. Proc Natl Acad Sci U S A 2020; 117:6502-6508. [PMID: 32139606 DOI: 10.1073/pnas.1920923117] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Carotenoids play a number of important roles in photosynthesis, primarily providing light-harvesting and photoprotective energy dissipation functions within pigment-protein complexes. The carbon-carbon double bond (C=C) conjugation length of carotenoids (N), generally between 9 and 15, determines the carotenoid-to-(bacterio)chlorophyll [(B)Chl] energy transfer efficiency. Here we purified and spectroscopically characterized light-harvesting complex 2 (LH2) from Rhodobacter sphaeroides containing the N = 7 carotenoid zeta (ζ)-carotene, not previously incorporated within a natural antenna complex. Transient absorption and time-resolved fluorescence show that, relative to the lifetime of the S1 state of ζ-carotene in solvent, the lifetime decreases ∼250-fold when ζ-carotene is incorporated within LH2, due to transfer of excitation energy to the B800 and B850 BChls a These measurements show that energy transfer proceeds with an efficiency of ∼100%, primarily via the S1 → Qx route because the S1 → S0 fluorescence emission of ζ-carotene overlaps almost perfectly with the Qx absorption band of the BChls. However, transient absorption measurements performed on microsecond timescales reveal that, unlike the native N ≥ 9 carotenoids normally utilized in light-harvesting complexes, ζ-carotene does not quench excited triplet states of BChl a, likely due to elevation of the ζ-carotene triplet energy state above that of BChl a These findings provide insights into the coevolution of photosynthetic pigments and pigment-protein complexes. We propose that the N ≥ 9 carotenoids found in light-harvesting antenna complexes represent a vital compromise that retains an acceptable level of energy transfer from carotenoids to (B)Chls while allowing acquisition of a new, essential function, namely, photoprotective quenching of harmful (B)Chl triplets.
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11
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Konold PE, van Stokkum IHM, Muzzopappa F, Wilson A, Groot ML, Kirilovsky D, Kennis JTM. Photoactivation Mechanism, Timing of Protein Secondary Structure Dynamics and Carotenoid Translocation in the Orange Carotenoid Protein. J Am Chem Soc 2019; 141:520-530. [PMID: 30511841 PMCID: PMC6331140 DOI: 10.1021/jacs.8b11373] [Citation(s) in RCA: 68] [Impact Index Per Article: 13.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2018] [Indexed: 01/10/2023]
Abstract
The orange carotenoid protein (OCP) is a two-domain photoactive protein that noncovalently binds an echinenone (ECN) carotenoid and mediates photoprotection in cyanobacteria. In the dark, OCP assumes an orange, inactive state known as OCPO; blue light illumination results in the red active state, known as OCPR. The OCPR state is characterized by large-scale structural changes that involve dissociation and separation of C-terminal and N-terminal domains accompanied by carotenoid translocation into the N-terminal domain. The mechanistic and dynamic-structural relations between photon absorption and formation of the OCPR state have remained largely unknown. Here, we employ a combination of time-resolved UV-visible and (polarized) mid-infrared spectroscopy to assess the electronic and structural dynamics of the carotenoid and the protein secondary structure, from femtoseconds to 0.5 ms. We identify a hereto unidentified carotenoid excited state in OCP, the so-called S* state, which we propose to play a key role in breaking conserved hydrogen-bond interactions between carotenoid and aromatic amino acids in the binding pocket. We arrive at a comprehensive reaction model where the hydrogen-bond rupture with conserved aromatic side chains at the carotenoid β1-ring in picoseconds occurs at a low yield of <1%, whereby the β1-ring retains a trans configuration with respect to the conjugated π-electron chain. This event initiates structural changes at the N-terminal domain in 1 μs, which allow the carotenoid to translocate into the N-terminal domain in 10 μs. We identified infrared signatures of helical elements that dock on the C-terminal domain β-sheet in the dark and unfold in the light to allow domain separation. These helical elements do not move within the experimental range of 0.5 ms, indicating that domain separation occurs on longer time scales, lagging carotenoid translocation by at least 2 decades of time.
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Affiliation(s)
- Patrick E. Konold
- Department of Physics
and Astronomy, Faculty of Sciences, Vrije
Universiteit, De Boelelaan
1081, 1081HV Amsterdam, The Netherlands
| | - Ivo H. M. van Stokkum
- Department of Physics
and Astronomy, Faculty of Sciences, Vrije
Universiteit, De Boelelaan
1081, 1081HV Amsterdam, The Netherlands
| | - Fernando Muzzopappa
- Institute for Integrative Biology of the
Cell (I2BC), CEA, CNRS, Universite Paris-Sud,
Universite Paris-Saclay, 91198 Gif-sur-Yvette, France
- Institut Joliot, Commissariat a l’Energie
Atomique (CEA), 91191 Gif-sur-Yvette, France
| | - Adjélé Wilson
- Institute for Integrative Biology of the
Cell (I2BC), CEA, CNRS, Universite Paris-Sud,
Universite Paris-Saclay, 91198 Gif-sur-Yvette, France
- Institut Joliot, Commissariat a l’Energie
Atomique (CEA), 91191 Gif-sur-Yvette, France
| | - Marie-Louise Groot
- Department of Physics
and Astronomy, Faculty of Sciences, Vrije
Universiteit, De Boelelaan
1081, 1081HV Amsterdam, The Netherlands
| | - Diana Kirilovsky
- Institute for Integrative Biology of the
Cell (I2BC), CEA, CNRS, Universite Paris-Sud,
Universite Paris-Saclay, 91198 Gif-sur-Yvette, France
- Institut Joliot, Commissariat a l’Energie
Atomique (CEA), 91191 Gif-sur-Yvette, France
| | - John T. M. Kennis
- Department of Physics
and Astronomy, Faculty of Sciences, Vrije
Universiteit, De Boelelaan
1081, 1081HV Amsterdam, The Netherlands
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12
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Excited-state dynamics of 3,3′-dihydroxyisorenieratene and (3R,3′R)-zeaxanthin: Observation of vibrationally hot S0 species. Arch Biochem Biophys 2018; 646:137-144. [DOI: 10.1016/j.abb.2018.03.035] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2018] [Revised: 03/13/2018] [Accepted: 03/26/2018] [Indexed: 11/19/2022]
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13
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Balevičius V, Lincoln CN, Viola D, Cerullo G, Hauer J, Abramavicius D. Effects of tunable excitation in carotenoids explained by the vibrational energy relaxation approach. PHOTOSYNTHESIS RESEARCH 2018; 135:55-64. [PMID: 28741055 DOI: 10.1007/s11120-017-0423-6] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/01/2017] [Accepted: 07/09/2017] [Indexed: 05/20/2023]
Abstract
Carotenoids are fundamental building blocks of natural light harvesters with convoluted and ultrafast energy deactivation networks. In order to disentangle such complex relaxation dynamics, several studies focused on transient absorption measurements and their dependence on the pump wavelength. However, such findings are inconclusive and sometimes contradictory. In this study, we compare internal conversion dynamics in [Formula: see text]-carotene, pumped at the first, second, and third vibronic progression peak. Instead of employing data fitting algorithms based on global analysis of the transient absorption spectra, we apply a fully quantum mechanical model to treat the high-frequency symmetric carbon-carbon (C=C and C-C) stretching modes explicitly. This model successfully describes observed population dynamics as well as spectral line shapes in their time-dependence and allows us to reach two conclusions: Firstly, the broadening of the induced absorption upon excess excitation is an effect of vibrational cooling in the first excited state ([Formula: see text]). Secondly, the internal conversion rate between the second excited state ([Formula: see text]) and [Formula: see text] crucially depends on the relative curve displacement. The latter point serves as a new perspective on solvent- and excitation wavelength-dependent experiments and lifts contradictions between several studies found in literature.
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Affiliation(s)
- Vytautas Balevičius
- School of Biological and Chemical Sciences, Queen Mary University of London, Mile End Road, London, E1 4NS, UK
| | - Craig N Lincoln
- Photonics Institute, TU Wien, Gusshausstr. 27, 1040, Vienna, Austria
| | - Daniele Viola
- IFN-CNR, Dipartimento di Fisica, Politecnico di Milano, Piazza Leonardo da Vinci 32, 20133, Milan, Italy
| | - Giulio Cerullo
- IFN-CNR, Dipartimento di Fisica, Politecnico di Milano, Piazza Leonardo da Vinci 32, 20133, Milan, Italy
| | - Jürgen Hauer
- Photonics Institute, TU Wien, Gusshausstr. 27, 1040, Vienna, Austria
| | - Darius Abramavicius
- Department of Theoretical Physics, Vilnius University, Sauletekio al. 9-III, 10222, Vilnius, Lithuania.
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14
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Gacek DA, Moore AL, Moore TA, Walla PJ. Two-Photon Spectra of Chlorophylls and Carotenoid–Tetrapyrrole Dyads. J Phys Chem B 2017; 121:10055-10063. [DOI: 10.1021/acs.jpcb.7b08502] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Daniel A. Gacek
- Technische Universität Braunschweig, Institute for Physical and Theoretical Chemistry, Department of Biophysical
Chemistry, Gaußstraße.
17, 38106 Braunschweig, Germany
| | - Ana L. Moore
- School
of Molecular Sciences and Center for Bioenergy and Photosynthesis, Arizona State University, Tempe, Arizona 85287-1604, United States
| | - Thomas A. Moore
- School
of Molecular Sciences and Center for Bioenergy and Photosynthesis, Arizona State University, Tempe, Arizona 85287-1604, United States
| | - Peter Jomo Walla
- Technische Universität Braunschweig, Institute for Physical and Theoretical Chemistry, Department of Biophysical
Chemistry, Gaußstraße.
17, 38106 Braunschweig, Germany
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15
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Kuznetsova V, Southall J, Cogdell RJ, Fuciman M, Polívka T. Spectroscopic properties of the S1 state of linear carotenoids after excess energy excitation. Chem Phys Lett 2017. [DOI: 10.1016/j.cplett.2017.03.009] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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16
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Niedzwiedzki DM, Swainsbury DJK, Martin EC, Hunter CN, Blankenship RE. Origin of the S* Excited State Feature of Carotenoids in Light-Harvesting Complex 1 from Purple Photosynthetic Bacteria. J Phys Chem B 2017; 121:7571-7585. [PMID: 28719215 DOI: 10.1021/acs.jpcb.7b04251] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
This spectroscopic study investigates the origin of the transient feature of the S* excited state of carotenoids bound in LH1 complexes from purple bacteria. The studies were performed on two RC-LH1 complexes from Rba. sphaeroides strains that bound carotenoids with different carbon-carbon double bond conjugation N, neurosporene (N = 9) and spirilloxanthin (N = 13). The S* transient spectral feature, originally associated with an elusive and optically silent excited state of spirilloxanthin in the LH1 complex, may be successfully explained and mimicked without involving any unknown electronic state. The spectral and temporal characteristics of the S* feature suggest that it is associated with triplet-triplet annihilation of carotenoid triplets formed after direct excitation of the molecule via a singlet fission mechanism. Depending on pigment homogeneity and carotenoid assembly in the LH1 complex, the spectro-temporal component associated with triplet-triplet annihilation may simply resolve a pure T-S spectrum of a carotenoid. In some cases (like spirilloxanthin), the T-S feature will also be accompanied by a carotenoid Stark spectrum and/or residual transient absorption of minor carotenoid species bound into LH1 antenna complex.
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Affiliation(s)
| | - David J K Swainsbury
- Department of Molecular Biology and Biotechnology, University of Sheffield , Sheffield S10 2TN, United Kingdom
| | - Elizabeth C Martin
- Department of Molecular Biology and Biotechnology, University of Sheffield , Sheffield S10 2TN, United Kingdom
| | - C Neil Hunter
- Department of Molecular Biology and Biotechnology, University of Sheffield , Sheffield S10 2TN, United Kingdom
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17
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Gdor I, Mani-Hazan M, Friedman N, Sheves M, Ruhman S. Membrane Independence of Ultrafast Photochemistry in Pharaonis Halorhodopsin: Testing the Role of Bacterioruberin. J Phys Chem B 2017; 121:2319-2325. [PMID: 28230358 DOI: 10.1021/acs.jpcb.6b12698] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Ultrafast photochemistry of pharaonis halorhodopsin (p-HR) in the intact membrane of Natronomonas pharaonis has been studied by photoselective femtosecond pump-hyperspectral probe spectroscopy with high time resolution. Two variants of this sample were studied, one with wild-type retinal prosthetic groups and another after shifting the retinal absorption deep into the blue range by reducing the Schiff base linkage, and the results were compared to a previous study on detergent-solubilized p-HR. This comparison shows that retinal photoisomerization dynamics is identical in the membrane and in the solubilized sample. Selective photoexcitation of bacterioruberin, which is associated with the protein in the native membrane, in wild-type and reduced samples, demonstrates conclusively that unlike the carotenoids associated with some bacterial retinal proteins the carrotenoid in p-HR does not act as a light-harvesting antenna.
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Affiliation(s)
- Itay Gdor
- Institute of Chemistry, the Hebrew University , Jerusalem 91904, Israel
| | - Maya Mani-Hazan
- Department of Organic Chemistry, Weizmann Institute of Science , Rehovot 76100, Israel
| | - Noga Friedman
- Department of Organic Chemistry, Weizmann Institute of Science , Rehovot 76100, Israel
| | - Mordechai Sheves
- Department of Organic Chemistry, Weizmann Institute of Science , Rehovot 76100, Israel
| | - Sanford Ruhman
- Institute of Chemistry, the Hebrew University , Jerusalem 91904, Israel
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18
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Niedzwiedzki DM, Dilbeck PL, Tang Q, Martin EC, Bocian DF, Hunter CN, Holten D. New insights into the photochemistry of carotenoid spheroidenone in light-harvesting complex 2 from the purple bacterium Rhodobacter sphaeroides. PHOTOSYNTHESIS RESEARCH 2017; 131:291-304. [PMID: 27854005 PMCID: PMC5313593 DOI: 10.1007/s11120-016-0322-2] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/26/2016] [Accepted: 10/24/2016] [Indexed: 06/06/2023]
Abstract
Light-harvesting complex 2 (LH2) from the semi-aerobically grown purple phototrophic bacterium Rhodobacter sphaeroides was studied using optical (static and time-resolved) and resonance Raman spectroscopies. This antenna complex comprises bacteriochlorophyll (BChl) a and the carotenoid spheroidenone, a ketolated derivative of spheroidene. The results indicate that the spheroidenone-LH2 complex contains two spectral forms of the carotenoid: (1) a minor, "blue" form with an S2 (11B u+ ) spectral origin band at 522 nm, shifted from the position in organic media simply by the high polarizability of the binding site, and (2) the major, "red" form with the origin band at 562 nm that is associated with a pool of pigments that more strongly interact with protein residues, most likely via hydrogen bonding. Application of targeted modeling of excited-state decay pathways after carotenoid excitation suggests that the high (92%) carotenoid-to-BChl energy transfer efficiency in this LH2 system, relative to LH2 complexes binding carotenoids with comparable double-bond conjugation lengths, derives mainly from resonance energy transfer from spheroidenone S2 (11B u+ ) state to BChl a via the Qx state of the latter, accounting for 60% of the total transfer. The elevated S2 (11B u+ ) → Qx transfer efficiency is apparently associated with substantially decreased energy gap (increased spectral overlap) between the virtual S2 (11B u+ ) → S0 (11A g- ) carotenoid emission and Qx absorption of BChl a. This reduced energetic gap is the ultimate consequence of strong carotenoid-protein interactions, including the inferred hydrogen bonding.
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Affiliation(s)
- Dariusz M Niedzwiedzki
- Department of Chemistry, Washington University in St. Louis, St. Louis, MO, 63130, USA.
- Photosynthetic Antenna Research Center, Washington University in St. Louis, Campus Box 1138, St. Louis, MO, 63130, USA.
| | - Preston L Dilbeck
- Department of Chemistry, Washington University in St. Louis, St. Louis, MO, 63130, USA
| | - Qun Tang
- Department of Chemistry, University of California Riverside, Riverside, CA, 92521, USA
| | - Elizabeth C Martin
- Department of Molecular Biology and Biotechnology, University of Sheffield, Sheffield, S10 2TN, UK
| | - David F Bocian
- Department of Chemistry, University of California Riverside, Riverside, CA, 92521, USA
| | - C Neil Hunter
- Department of Molecular Biology and Biotechnology, University of Sheffield, Sheffield, S10 2TN, UK
| | - Dewey Holten
- Department of Chemistry, Washington University in St. Louis, St. Louis, MO, 63130, USA
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19
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Niedzwiedzki DM, Hunter CN, Blankenship RE. Evaluating the Nature of So-Called S*-State Feature in Transient Absorption of Carotenoids in Light-Harvesting Complex 2 (LH2) from Purple Photosynthetic Bacteria. J Phys Chem B 2016; 120:11123-11131. [PMID: 27726397 PMCID: PMC5098231 DOI: 10.1021/acs.jpcb.6b08639] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
![]()
Carotenoids
are a class of natural pigments present in all phototrophic
organisms, mainly in their light-harvesting proteins in which they
play roles of accessory light absorbers and photoprotectors. Extensive
time-resolved spectroscopic studies of these pigments have revealed
unexpectedly complex photophysical properties, particularly for carotenoids
in light-harvesting LH2 complexes from purple bacteria. An ambiguous,
optically forbidden electronic excited state designated as S* has
been postulated to be involved in carotenoid excitation relaxation
and in an alternative carotenoid-to-bacteriochlorophyll energy transfer
pathway, as well as being a precursor of the carotenoid triplet state.
However, no definitive and satisfactory origin of the carotenoid S*
state in these complexes has been established, despite a wide-ranging
series of studies. Here, we resolve the ambiguous origin of the carotenoid
S* state in LH2 complex from Rba. sphaeroides by
showing that the S* feature can be seen as a combination of ground
state absorption bleaching of the carotenoid pool converted to cations
and the Stark spectrum of neighbor neutral carotenoids, induced by
temporal electric field brought by the carotenoid cation–bacteriochlorophyll
anion pair. These findings remove the need to assign an S* state,
and thereby significantly simplify the photochemistry of carotenoids
in these photosynthetic antenna complexes.
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Affiliation(s)
| | - C Neil Hunter
- Department of Molecular Biology and Biotechnology, University of Sheffield , Sheffield S10 2TN, United Kingdom
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20
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Balevičius V, Abramavicius D, Polívka T, Galestian
Pour A, Hauer J. A Unified Picture of S* in Carotenoids. J Phys Chem Lett 2016; 7:3347-3352. [PMID: 27509302 PMCID: PMC5011297 DOI: 10.1021/acs.jpclett.6b01455] [Citation(s) in RCA: 53] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2016] [Accepted: 08/10/2016] [Indexed: 05/29/2023]
Abstract
In π-conjugated chain molecules such as carotenoids, coupling between electronic and vibrational degrees of freedom is of central importance. It governs both dynamic and static properties, such as the time scales of excited state relaxation as well as absorption spectra. In this work, we treat vibronic dynamics in carotenoids on four electronic states (|S0⟩, |S1⟩, |S2⟩, and |Sn⟩) in a physically rigorous framework. This model explains all features previously associated with the intensely debated S* state. Besides successfully fitting transient absorption data of a zeaxanthin homologue, this model also accounts for previous results from global target analysis and chain length-dependent studies. Additionally, we are able to incorporate findings from pump-deplete-probe experiments, which were incompatible to any pre-existing model. Thus, we present the first comprehensive and unified interpretation of S*-related features, explaining them by vibronic transitions on either S1, S0, or both, depending on the chain length of the investigated carotenoid.
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Affiliation(s)
- Vytautas Balevičius
- Department
of Theoretical Physics, Faculty of Physics, Vilnius University, Sauletekio Avenue 9, Building 3, LT-10222 Vilnius, Lithuania
| | - Darius Abramavicius
- Department
of Theoretical Physics, Faculty of Physics, Vilnius University, Sauletekio Avenue 9, Building 3, LT-10222 Vilnius, Lithuania
| | - Tomáš Polívka
- Institute
of Physics and Biophysics, Faculty of Science, University of South Bohemia, Branišovská 1760, 37005 České Budějovice, Czech
Republic
| | | | - Jürgen Hauer
- Photonics
Institute, TU Wien, Gusshausstrasse
27, 1040 Vienna, Austria
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21
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Challenges facing an understanding of the nature of low-energy excited states in photosynthesis. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2016; 1857:1627-1640. [PMID: 27372198 DOI: 10.1016/j.bbabio.2016.06.010] [Citation(s) in RCA: 63] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/18/2016] [Revised: 06/27/2016] [Accepted: 06/28/2016] [Indexed: 01/09/2023]
Abstract
While the majority of the photochemical states and pathways related to the biological capture of solar energy are now well understood and provide paradigms for artificial device design, additional low-energy states have been discovered in many systems with obscure origins and significance. However, as low-energy states are naively expected to be critical to function, these observations pose important challenges. A review of known properties of low energy states covering eight photochemical systems, and options for their interpretation, are presented. A concerted experimental and theoretical research strategy is suggested and outlined, this being aimed at providing a fully comprehensive understanding.
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22
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Dilbeck PL, Tang Q, Mothersole DJ, Martin EC, Hunter CN, Bocian DF, Holten D, Niedzwiedzki DM. Quenching Capabilities of Long-Chain Carotenoids in Light-Harvesting-2 Complexes from Rhodobacter sphaeroides with an Engineered Carotenoid Synthesis Pathway. J Phys Chem B 2016; 120:5429-43. [PMID: 27285777 PMCID: PMC4921951 DOI: 10.1021/acs.jpcb.6b03305] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
![]()
Six light-harvesting-2 complexes
(LH2) from genetically modified
strains of the purple photosynthetic bacterium Rhodobacter
(Rb.) sphaeroides were studied using static and ultrafast
optical methods and resonance Raman spectroscopy. These strains were
engineered to incorporate carotenoids for which the number of conjugated
groups (N = NC=C + NC=O) varies from 9 to 15.
The Rb. sphaeroides strains incorporate their native
carotenoids spheroidene (N = 10) and spheroidenone
(N = 11), as well as longer-chain analogues including
spirilloxanthin (N = 13) and diketospirilloxantion
(N = 15) normally found in Rhodospirillum
rubrum. Measurements of the properties of the carotenoid
first singlet excited state (S1) in antennas from the Rb. sphaeroides set show that carotenoid-bacteriochlorophyll a (BChl a) interactions are similar to
those in LH2 complexes from various other bacterial species and thus
are not significantly impacted by differences in polypeptide composition.
Instead, variations in carotenoid-to-BChl a energy
transfer are primarily regulated by the N-determined
energy of the carotenoid S1 excited state, which for long-chain
(N ≥ 13) carotenoids is not involved in energy
transfer. Furthermore, the role of the long-chain carotenoids switches
from a light-harvesting supporter (via energy transfer to BChl a) to a quencher of the BChl a S1 excited state B850*. This quenching is manifested as a substantial
(∼2-fold) reduction of the B850* lifetime and the B850* fluorescence
quantum yield for LH2 housing the longest carotenoids.
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Affiliation(s)
| | - Qun Tang
- Department of Chemistry, University of California Riverside , Riverside, California 92521, United States
| | - David J Mothersole
- Department of Molecular Biology and Biotechnology, University of Sheffield , Sheffield S10 2TN, United Kingdom
| | - Elizabeth C Martin
- Department of Molecular Biology and Biotechnology, University of Sheffield , Sheffield S10 2TN, United Kingdom
| | - C Neil Hunter
- Department of Molecular Biology and Biotechnology, University of Sheffield , Sheffield S10 2TN, United Kingdom
| | - David F Bocian
- Department of Chemistry, University of California Riverside , Riverside, California 92521, United States
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23
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Yi J, Xiong Y, Cheng K, Li M, Chu G, Pu X, Xu T. A Combination of Chemometrics and Quantum Mechanics Methods Applied to Analysis of Femtosecond Transient Absorption Spectrum of Ortho-Nitroaniline. Sci Rep 2016; 6:19364. [PMID: 26781083 PMCID: PMC4726040 DOI: 10.1038/srep19364] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2015] [Accepted: 12/11/2015] [Indexed: 12/19/2022] Open
Abstract
A combination of the advanced chemometrics method with quantum mechanics calculation was for the first time applied to explore a facile yet efficient analysis strategy to thoroughly resolve femtosecond transient absorption spectroscopy of ortho-nitroaniline (ONA), served as a model compound of important nitroaromatics and explosives. The result revealed that the ONA molecule is primarily excited to S3 excited state from the ground state and then ultrafast relaxes to S2 state. The internal conversion from S2 to S1 occurs within 0.9 ps. One intermediate state S* was identified in the intersystem crossing (ISC) process, which is different from the specific upper triplet receiver state proposed in some other nitroaromatics systems. The S1 state decays to the S* one within 6.4 ps and then intersystem crossing to the lowest triplet state within 19.6 ps. T1 was estimated to have a lifetime up to 2 ns. The relatively long S* state and very long-lived T1 one should play a vital role as precursors to various nitroaromatic and explosive photoproducts.
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Affiliation(s)
- Jing Yi
- College of Chemistry, Sichuan University, Chengdu 610064, People's Republic of China
| | - Ying Xiong
- Institute of Chemical Material, China Academy of Engineering Physics (CAEP), Mianyang 621900, People's Republic of China
| | - Kemei Cheng
- Institute of Chemical Material, China Academy of Engineering Physics (CAEP), Mianyang 621900, People's Republic of China
| | - Menglong Li
- College of Chemistry, Sichuan University, Chengdu 610064, People's Republic of China
| | - Genbai Chu
- Science and Technology on Plasma Physics Laboratory, Research Center of Laser Fusion, CAEP, Mianyang 621900, People's Republic of China
| | - Xuemei Pu
- College of Chemistry, Sichuan University, Chengdu 610064, People's Republic of China
| | - Tao Xu
- Institute of Chemical Material, China Academy of Engineering Physics (CAEP), Mianyang 621900, People's Republic of China
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24
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Kloz M, Weißenborn J, Polívka T, Frank HA, Kennis JTM. Spectral watermarking in femtosecond stimulated Raman spectroscopy: resolving the nature of the carotenoid S* state. Phys Chem Chem Phys 2016; 18:14619-28. [DOI: 10.1039/c6cp01464j] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
A new method for recording femtosecond stimulated Raman spectra was developed that dramatically improves and automatizes baseline problems.
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Affiliation(s)
- Miroslav Kloz
- Department of Physics and Astronomy
- VU University Amsterdam
- 1081HV Amsterdam
- The Netherlands
- ELI-Beamlines
| | - Jörn Weißenborn
- Department of Physics and Astronomy
- VU University Amsterdam
- 1081HV Amsterdam
- The Netherlands
| | - Tomáš Polívka
- University of South Bohemia
- 370 05 České Budějovice
- Czech Republic
| | - Harry A. Frank
- Department of Chemistry
- University of Connecticut
- Storrs
- USA
| | - John T. M. Kennis
- Department of Physics and Astronomy
- VU University Amsterdam
- 1081HV Amsterdam
- The Netherlands
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25
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Staleva H, Zeeshan M, Chábera P, Partali V, Sliwka HR, Polívka T. Ultrafast Dynamics of Long Homologues of Carotenoid Zeaxanthin. J Phys Chem A 2015; 119:11304-12. [PMID: 26502350 DOI: 10.1021/acs.jpca.5b08460] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Three zeaxanthin homologues with conjugation lengths N of 15, 19, and 23 denoted as Z15, Z19, and Z23 were studied by femtosecond transient absorption spectroscopy, and the results were compared to those obtained for zeaxanthin (Z11). The energies of S2 decrease from 20 450 cm(-1) (Z11) to 18 280 cm(-1) (Z15), 17 095 cm(-1) (Z19), and 16 560 cm(-1) (Z23). Fitting the N dependence of the S2 energies allowed the estimation of [Formula: see text], the S2 energy of a hypothetical infinite zeaxanthin, to be ∼14 000 cm(-1). Exciting the 0-0 band of the S2 state produces characteristic S1-Sn spectral profiles in transient absorption spectra with maxima at 556 nm (Z11), 630 nm (Z15), 690 nm (Z19), and 740 nm (Z23). The red shift of the S1-Sn transition with increasing conjugation length is caused by a decrease in the S1 state energy, resulting in S1 lifetimes of 9 ps (Z11), 0.9 ps (Z15), 0.35 ps (Z19), and 0.19 ps (Z23). Essentially the same lifetimes were obtained after excess energy excitation at 400 nm, but S1-Sn becomes broader, indicating a larger conformation disorder in the S1 state after 400 nm excitation compared to excitation into the 0-0 band of the S2 state. An S* signal was observed in all samples, but only for Z15, Z19, and Z23 does the S* signal decay with a lifetime different from that of the S1 state. The S* lifetimes are 2.9 and 1.6 ps for Z15 and Z19, respectively. In Z23 the S* signal needs two decay components yielding lifetimes of 0.24 and 2.3 ps. The S* signal is more pronounced after 400 nm excitation.
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Affiliation(s)
- Hristina Staleva
- Institute of Physics and Biophysics, Faculty of Science, University of South Bohemia , Branišovská 1760, 37005 České Budějovice, Czech Republic
| | - Muhammad Zeeshan
- Department of Chemistry, Norwegian University of Science and Technology , 7491 Trondheim, Norway
| | - Pavel Chábera
- Department of Chemical Physics, Lund University , SE-221 00 Lund, Sweden
| | - Vassilia Partali
- Department of Chemistry, Norwegian University of Science and Technology , 7491 Trondheim, Norway
| | - Hans-Richard Sliwka
- Department of Chemistry, Norwegian University of Science and Technology , 7491 Trondheim, Norway
| | - Tomáš Polívka
- Institute of Physics and Biophysics, Faculty of Science, University of South Bohemia , Branišovská 1760, 37005 České Budějovice, Czech Republic
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26
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Quick M, Kasper MA, Richter C, Mahrwald R, Dobryakov AL, Kovalenko SA, Ernsting NP. β-Carotene Revisited by Transient Absorption and Stimulated Raman Spectroscopy. Chemphyschem 2015; 16:3824-35. [DOI: 10.1002/cphc.201500586] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2015] [Indexed: 12/21/2022]
Affiliation(s)
- Martin Quick
- Department of Chemistry; Humboldt-Universität zu Berlin; Brook-Taylor-Str. 2 12489 Berlin Germany
| | - Marc-André Kasper
- Department of Chemistry; Humboldt-Universität zu Berlin; Brook-Taylor-Str. 2 12489 Berlin Germany
| | - Celin Richter
- Department of Chemistry; Humboldt-Universität zu Berlin; Brook-Taylor-Str. 2 12489 Berlin Germany
| | - Rainer Mahrwald
- Department of Chemistry; Humboldt-Universität zu Berlin; Brook-Taylor-Str. 2 12489 Berlin Germany
| | - Alexander L. Dobryakov
- Department of Chemistry; Humboldt-Universität zu Berlin; Brook-Taylor-Str. 2 12489 Berlin Germany
| | - Sergey A. Kovalenko
- Department of Chemistry; Humboldt-Universität zu Berlin; Brook-Taylor-Str. 2 12489 Berlin Germany
| | - Nikolaus P. Ernsting
- Department of Chemistry; Humboldt-Universität zu Berlin; Brook-Taylor-Str. 2 12489 Berlin Germany
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27
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Di Donato M, Ragnoni E, Lapini A, Foggi P, Hiller RG, Righini R. Femtosecond transient infrared and stimulated Raman spectroscopy shed light on the relaxation mechanisms of photo-excited peridinin. J Chem Phys 2015; 142:212409. [DOI: 10.1063/1.4915072] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
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28
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van Oort B, van Grondelle R, van Stokkum IHM. A Hidden State in Light-Harvesting Complex II Revealed By Multipulse Spectroscopy. J Phys Chem B 2015; 119:5184-93. [PMID: 25815531 PMCID: PMC4500649 DOI: 10.1021/acs.jpcb.5b01335] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2015] [Revised: 03/23/2015] [Indexed: 11/28/2022]
Abstract
Light-harvesting complex II (LHCII) is pivotal both for collecting solar radiation for photosynthesis, and for protection against photodamage under high light intensities (via a process called nonphotochemical quenching, NPQ). Aggregation of LHCII is associated with fluorescence quenching, and is used as an in vitro model system of NPQ. However, there is no agreement on the nature of the quencher and on the validity of aggregation as a model system. Here, we use ultrafast multipulse spectroscopy to populate a quenched state in unquenched (unaggregated) LHCII. The state shows characteristic features of lutein and chlorophyll, suggesting that it is an excitonically coupled state between these two compounds. This state decays in approximately 10 ps, making it a strong competitor for photodamage and photochemical quenching. It is observed in trimeric and monomeric LHCII, upon re-excitation with pulses of different wavelengths and duration. We propose that this state is always present, but is scarcely populated under low light intensities. Under high light intensities it may become more accessible, e.g. by conformational changes, and then form a quenching channel. The same state may be the cause of fluorescence blinking observed in single-molecule spectroscopy of LHCII trimers, where a small subpopulation is in an energetically higher state where the pathway to the quencher opens up.
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Affiliation(s)
- Bart van Oort
- Department
of Physics and Astronomy, Faculty of Sciences, VU University Amsterdam, De Boelelaan 1081, 1081 HV Amsterdam, The Netherlands
- Institute
for Lasers, Life and Biophotonics, Faculty of Sciences, VU University Amsterdam, De Boelelaan 1081, 1081 HV Amsterdam, The Netherlands
| | - Rienk van Grondelle
- Department
of Physics and Astronomy, Faculty of Sciences, VU University Amsterdam, De Boelelaan 1081, 1081 HV Amsterdam, The Netherlands
- Institute
for Lasers, Life and Biophotonics, Faculty of Sciences, VU University Amsterdam, De Boelelaan 1081, 1081 HV Amsterdam, The Netherlands
| | - Ivo H. M. van Stokkum
- Department
of Physics and Astronomy, Faculty of Sciences, VU University Amsterdam, De Boelelaan 1081, 1081 HV Amsterdam, The Netherlands
- Institute
for Lasers, Life and Biophotonics, Faculty of Sciences, VU University Amsterdam, De Boelelaan 1081, 1081 HV Amsterdam, The Netherlands
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29
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Musser AJ, Maiuri M, Brida D, Cerullo G, Friend RH, Clark J. The nature of singlet exciton fission in carotenoid aggregates. J Am Chem Soc 2015; 137:5130-9. [PMID: 25825939 PMCID: PMC4440407 DOI: 10.1021/jacs.5b01130] [Citation(s) in RCA: 118] [Impact Index Per Article: 13.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Singlet exciton fission allows the fast and efficient generation of two spin triplet states from one photoexcited singlet. It has the potential to improve organic photovoltaics, enabling efficient coupling to the blue to ultraviolet region of the solar spectrum to capture the energy generally lost as waste heat. However, many questions remain about the underlying fission mechanism. The relation between intermolecular geometry and singlet fission rate and yield is poorly understood and remains one of the most significant barriers to the design of new singlet fission sensitizers. Here we explore the structure-property relationship and examine the mechanism of singlet fission in aggregates of astaxanthin, a small polyene. We isolate five distinct supramolecular structures of astaxanthin generated through self-assembly in solution. Each is capable of undergoing intermolecular singlet fission, with rates of triplet generation and annihilation that can be correlated with intermolecular coupling strength. In contrast with the conventional model of singlet fission in linear molecules, we demonstrate that no intermediate states are involved in the triplet formation: instead, singlet fission occurs directly from the initial 1B(u) photoexcited state on ultrafast time scales. This result demands a re-evaluation of current theories of polyene photophysics and highlights the robustness of carotenoid singlet fission.
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Affiliation(s)
- Andrew J Musser
- †Cavendish Laboratory, University of Cambridge, Cambridge CB3 0HE, United Kingdom
| | - Margherita Maiuri
- ‡IFN-CNR, Dipartimento di Fisica, Politecnico di Milano, I-20133 Milano, Italy
| | - Daniele Brida
- §Department of Physics and Center for Applied Photonics, University of Konstanz, D-78457 Konstanz, Germany
| | - Giulio Cerullo
- ‡IFN-CNR, Dipartimento di Fisica, Politecnico di Milano, I-20133 Milano, Italy
| | - Richard H Friend
- †Cavendish Laboratory, University of Cambridge, Cambridge CB3 0HE, United Kingdom
| | - Jenny Clark
- ∥Department of Physics and Astronomy, University of Sheffield, Sheffield S3 7RH, United Kingdom
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30
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Balevičius V, Pour AG, Savolainen J, Lincoln CN, Lukeš V, Riedle E, Valkunas L, Abramavicius D, Hauer J. Vibronic energy relaxation approach highlighting deactivation pathways in carotenoids. Phys Chem Chem Phys 2015; 17:19491-9. [DOI: 10.1039/c5cp00856e] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Energy relaxation between two electronic states of a molecule is mediated by a set of relevant vibrational states.
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Affiliation(s)
- Vytautas Balevičius
- Department of Theoretical Physics
- Faculty of Physics
- Vilnius University
- LT-10222 Vilnius
- Lithuania
| | | | - Janne Savolainen
- Department of Physical Chemistry II
- Ruhr-University Bochum
- 44780 Bochum
- Germany
| | - Craig N. Lincoln
- Photonics Institute
- Vienna University of Technology
- 1040 Vienna
- Austria
| | - Vladimír Lukeš
- Department of Chemical Physics
- Slovak University of Technology
- 81237 Bratislava
- Slovakia
| | - Eberhard Riedle
- Lehrstuhl für BioMolekulare Optik
- Ludwig-Maximilians-University
- 80538 Munich
- Germany
| | - Leonas Valkunas
- Department of Theoretical Physics
- Faculty of Physics
- Vilnius University
- LT-10222 Vilnius
- Lithuania
| | - Darius Abramavicius
- Department of Theoretical Physics
- Faculty of Physics
- Vilnius University
- LT-10222 Vilnius
- Lithuania
| | - Jürgen Hauer
- Photonics Institute
- Vienna University of Technology
- 1040 Vienna
- Austria
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31
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Ehlers F, Scholz M, Schimpfhauser J, Bienert J, Oum K, Lenzer T. Collisional relaxation of apocarotenals: identifying the S* state with vibrationally excited molecules in the ground electronic state S0*. Phys Chem Chem Phys 2015; 17:10478-88. [DOI: 10.1039/c4cp05600k] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The S* signal of carotenoids corresponds to vibrationally hot molecules in the ground electronic state S0*.
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Affiliation(s)
- Florian Ehlers
- Georg-August-Universität Göttingen
- Institut für Physikalische Chemie
- 37077 Göttingen
- Germany
| | - Mirko Scholz
- Universität Siegen
- Physikalische Chemie 2
- 57076 Siegen
- Germany
| | | | - Jürgen Bienert
- Max-Planck-Institut für biophysikalische Chemie
- 37077 Göttingen
- Germany
| | - Kawon Oum
- Universität Siegen
- Physikalische Chemie 2
- 57076 Siegen
- Germany
| | - Thomas Lenzer
- Universität Siegen
- Physikalische Chemie 2
- 57076 Siegen
- Germany
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32
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Ragnoni E, Di Donato M, Iagatti A, Lapini A, Righini R. Mechanism of the Intramolecular Charge Transfer State Formation in all-trans-β-Apo-8′-carotenal: Influence of Solvent Polarity and Polarizability. J Phys Chem B 2014; 119:420-32. [DOI: 10.1021/jp5093288] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Elena Ragnoni
- LENS (European
Laboratory for Non-Linear Spectroscopy) via N. Carrara 1, 50019 Sesto Fiorentino (Florence) Italy
- INO (Istituto
Nazionale di Ottica), Largo Fermi 6, 50125 Firenze, Italy
| | - Mariangela Di Donato
- LENS (European
Laboratory for Non-Linear Spectroscopy) via N. Carrara 1, 50019 Sesto Fiorentino (Florence) Italy
- INO (Istituto
Nazionale di Ottica), Largo Fermi 6, 50125 Firenze, Italy
- Dipartimento
di Chimica “Ugo Schiff”, Università di Firenze, via della
Lastruccia 13, 50019 Sesto Fiorentino (Florence), Italy
| | - Alessandro Iagatti
- LENS (European
Laboratory for Non-Linear Spectroscopy) via N. Carrara 1, 50019 Sesto Fiorentino (Florence) Italy
- INO (Istituto
Nazionale di Ottica), Largo Fermi 6, 50125 Firenze, Italy
| | - Andrea Lapini
- LENS (European
Laboratory for Non-Linear Spectroscopy) via N. Carrara 1, 50019 Sesto Fiorentino (Florence) Italy
- INO (Istituto
Nazionale di Ottica), Largo Fermi 6, 50125 Firenze, Italy
- Dipartimento
di Chimica “Ugo Schiff”, Università di Firenze, via della
Lastruccia 13, 50019 Sesto Fiorentino (Florence), Italy
| | - Roberto Righini
- LENS (European
Laboratory for Non-Linear Spectroscopy) via N. Carrara 1, 50019 Sesto Fiorentino (Florence) Italy
- INO (Istituto
Nazionale di Ottica), Largo Fermi 6, 50125 Firenze, Italy
- Dipartimento
di Chimica “Ugo Schiff”, Università di Firenze, via della
Lastruccia 13, 50019 Sesto Fiorentino (Florence), Italy
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33
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Magdaong N, LaFountain AM, Greco JA, Gardiner AT, Carey AM, Cogdell RJ, Gibson GN, Birge RR, Frank HA. High efficiency light harvesting by carotenoids in the LH2 complex from photosynthetic bacteria: unique adaptation to growth under low-light conditions. J Phys Chem B 2014; 118:11172-89. [PMID: 25171303 PMCID: PMC4174993 DOI: 10.1021/jp5070984] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2014] [Revised: 08/26/2014] [Indexed: 12/03/2022]
Abstract
Rhodopin, rhodopinal, and their glucoside derivatives are carotenoids that accumulate in different amounts in the photosynthetic bacterium, Rhodoblastus (Rbl.) acidophilus strain 7050, depending on the intensity of the light under which the organism is grown. The different growth conditions also have a profound effect on the spectra of the bacteriochlorophyll (BChl) pigments that assemble in the major LH2 light-harvesting pigment-protein complex. Under high-light conditions the well-characterized B800-850 LH2 complex is formed and accumulates rhodopin and rhodopin glucoside as the primary carotenoids. Under low-light conditions, a variant LH2, denoted B800-820, is formed, and rhodopinal and rhodopinal glucoside are the most abundant carotenoids. The present investigation compares and contrasts the spectral properties and dynamics of the excited states of rhodopin and rhodopinal in solution. In addition, the systematic differences in pigment composition and structure of the chromophores in the LH2 complexes provide an opportunity to explore the effect of these factors on the rate and efficiency of carotenoid-to-BChl energy transfer. It is found that the enzymatic conversion of rhodopin to rhodopinal by Rbl. acidophilus 7050 grown under low-light conditions results in nearly 100% carotenoid-to-BChl energy transfer efficiency in the LH2 complex. This comparative analysis provides insight into how photosynthetic systems are able to adapt and survive under challenging environmental conditions.
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Affiliation(s)
- Nikki
M. Magdaong
- Department
of Chemistry, University of Connecticut, Storrs, Connecticut 06269, United States
| | - Amy M. LaFountain
- Department
of Chemistry, University of Connecticut, Storrs, Connecticut 06269, United States
| | - Jordan A. Greco
- Department
of Chemistry, University of Connecticut, Storrs, Connecticut 06269, United States
| | - Alastair T. Gardiner
- Institute
of Molecular Cell and Systems Biology, University
of Glasgow, Glasgow G12 8TA, Scotland
| | - Anne-Marie Carey
- Institute
of Molecular Cell and Systems Biology, University
of Glasgow, Glasgow G12 8TA, Scotland
| | - Richard J. Cogdell
- Institute
of Molecular Cell and Systems Biology, University
of Glasgow, Glasgow G12 8TA, Scotland
| | - George N. Gibson
- Department
of Physics, University of Connecticut, Storrs, Connecticut 06269, United States
| | - Robert R. Birge
- Department
of Chemistry, University of Connecticut, Storrs, Connecticut 06269, United States
| | - Harry A. Frank
- Department
of Chemistry, University of Connecticut, Storrs, Connecticut 06269, United States
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34
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Di Donato M, Segado Centellas M, Lapini A, Lima M, Avila F, Santoro F, Cappelli C, Righini R. Combination of transient 2D-IR experiments and ab initio computations sheds light on the formation of the charge-transfer state in photoexcited carbonyl carotenoids. J Phys Chem B 2014; 118:9613-30. [PMID: 25050938 DOI: 10.1021/jp505473j] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The excited state dynamics of carbonyl carotenoids is very complex because of the coupling of single- and doubly excited states and the possible involvement of intramolecular charge-transfer (ICT) states. In this contribution we employ ultrafast infrared spectroscopy and theoretical computations to investigate the relaxation dynamics of trans-8'-apo-β-carotenal occurring on the picosecond time scale, after excitation in the S2 state. In a (slightly) polar solvent like chloroform, one-dimensional (T1D-IR) and two-dimensional (T2D-IR) transient infrared spectroscopy reveal spectral components with characteristic frequencies and lifetimes that are not observed in nonpolar solvents (cyclohexane). Combining experimental evidence with an analysis of CASPT2//CASSCF ground and excited state minima and energy profiles, complemented with TDDFT calculations in gas phase and in solvent, we propose a photochemical decay mechanism for this system where only the bright single-excited 1Bu(+) and the dark double-excited 2Ag(-) states are involved. Specifically, the initially populated 1Bu(+) relaxes toward 2Ag(-) in 200 fs. In a nonpolar solvent 2Ag(-) decays to the ground state (GS) in 25 ps. In polar solvents, distortions along twisting modes of the chain promote a repopulation of the 1Bu(+) state which then quickly relaxes to the GS (18 ps in chloroform). The 1Bu(+) state has a high electric dipole and is the main contributor to the charge-transfer state involved in the dynamics in polar solvents. The 2Ag(-) → 1Bu(+) population transfer is evidenced by a cross peak on the T2D-IR map revealing that the motions along the same stretching of the conjugated chain on the 2Ag(-) and 1Bu(+) states are coupled.
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Affiliation(s)
- Mariangela Di Donato
- LENS (European Laboratory for Nonlinear Spectroscopy) via N. Carrara 1, 50019 Sesto Fiorentino (FI), Italy
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35
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Maiuri M, Snellenburg JJ, van Stokkum IHM, Pillai S, WongCarter K, Gust D, Moore TA, Moore AL, van Grondelle R, Cerullo G, Polli D. Ultrafast Energy Transfer and Excited State Coupling in an Artificial Photosynthetic Antenna. J Phys Chem B 2013; 117:14183-90. [DOI: 10.1021/jp401073w] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- M. Maiuri
- IFN-CNR, Dipartimento di Fisica, Politecnico di Milano, Piazza L. da Vinci, 32, 20133 Milano, Italy
| | - J. J. Snellenburg
- Department of Physics
and Astronomy, VU University Amsterdam, De Boelelaan 1081, 1081HV Amsterdam, The Netherlands
| | - I. H. M. van Stokkum
- Department of Physics
and Astronomy, VU University Amsterdam, De Boelelaan 1081, 1081HV Amsterdam, The Netherlands
| | - S. Pillai
- Department of Chemistry & Biochemistry and The Center for Bioenergy and Photosynthesis, Arizona State University, Tempe, Arizona 85287-1605, United States
| | - K. WongCarter
- Department of Chemistry & Biochemistry and The Center for Bioenergy and Photosynthesis, Arizona State University, Tempe, Arizona 85287-1605, United States
| | - D. Gust
- Department of Chemistry & Biochemistry and The Center for Bioenergy and Photosynthesis, Arizona State University, Tempe, Arizona 85287-1605, United States
| | - T. A. Moore
- Department of Chemistry & Biochemistry and The Center for Bioenergy and Photosynthesis, Arizona State University, Tempe, Arizona 85287-1605, United States
| | - A. L. Moore
- Department of Chemistry & Biochemistry and The Center for Bioenergy and Photosynthesis, Arizona State University, Tempe, Arizona 85287-1605, United States
| | - R. van Grondelle
- Department of Physics
and Astronomy, VU University Amsterdam, De Boelelaan 1081, 1081HV Amsterdam, The Netherlands
| | - G. Cerullo
- IFN-CNR, Dipartimento di Fisica, Politecnico di Milano, Piazza L. da Vinci, 32, 20133 Milano, Italy
| | - D. Polli
- IFN-CNR, Dipartimento di Fisica, Politecnico di Milano, Piazza L. da Vinci, 32, 20133 Milano, Italy
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36
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Knecht S, Marian CM, Kongsted J, Mennucci B. On the photophysics of carotenoids: a multireference DFT study of peridinin. J Phys Chem B 2013; 117:13808-15. [PMID: 24090414 DOI: 10.1021/jp4078739] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
We present a quantum-mechanical investigation of the photophysics of a specific carotenoid, peridinin, which is present in light-harvesting complexes. The fundamental role played by the geometry in determining the position and character of its low-lying singlet electronic states is investigated using a multireference DFT approach in combination with a continuum solvation model. The main photophysical properties of peridinin appear to be governed by the lowest two singlet excited states, as no evidence points to an intermediate S* state and the energies of the upper excited states are too high to allow their population with excitation in the visible range. These two excited states (S1, 2(1)A(g)(-) and S2, 1(1)B(u)(+)) are highly connected through the conjugation path here characterized by the value of the bond length alternation (BLA). The S1 and S2 states present distinct natures for small BLA values, whereas for larger ones they become more similar in terms of both brightness and dipolar character and their energies become closer. The geometrical issue is thus of fundamental importance for a correct interpretation of the spectroscopic signatures of peridinin.
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Affiliation(s)
- Stefan Knecht
- Laboratory of Physical Chemistry, ETH Zürich , Wolfgang-Pauli-Straße 10, 8093 Zürich, Switzerland
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37
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Chang CW, Gottlieb SM, Kim PW, Rockwell NC, Lagarias JC, Larsen DS. Reactive Ground-State Pathways Are Not Ubiquitous in Red/Green Cyanobacteriochromes. J Phys Chem B 2013; 117:11229-38. [DOI: 10.1021/jp402112u] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Che-Wei Chang
- Department of Chemistry and ‡Department of
Molecular and Cellular Biology, University of California, Davis, One Shields Avenue, Davis, California
95616
| | - Sean M. Gottlieb
- Department of Chemistry and ‡Department of
Molecular and Cellular Biology, University of California, Davis, One Shields Avenue, Davis, California
95616
| | - Peter W. Kim
- Department of Chemistry and ‡Department of
Molecular and Cellular Biology, University of California, Davis, One Shields Avenue, Davis, California
95616
| | - Nathan C. Rockwell
- Department of Chemistry and ‡Department of
Molecular and Cellular Biology, University of California, Davis, One Shields Avenue, Davis, California
95616
| | - J. Clark Lagarias
- Department of Chemistry and ‡Department of
Molecular and Cellular Biology, University of California, Davis, One Shields Avenue, Davis, California
95616
| | - Delmar S. Larsen
- Department of Chemistry and ‡Department of
Molecular and Cellular Biology, University of California, Davis, One Shields Avenue, Davis, California
95616
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38
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Hauer J, Maiuri M, Viola D, Lukes V, Henry S, Carey AM, Cogdell RJ, Cerullo G, Polli D. Explaining the temperature dependence of spirilloxanthin's S* signal by an inhomogeneous ground state model. J Phys Chem A 2013; 117:6303-10. [PMID: 23577754 PMCID: PMC3725610 DOI: 10.1021/jp4011372] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
![]()
We
investigate the nature of the S* excited state in carotenoids by performing
a series of pump–probe experiments with sub-20 fs time resolution
on spirilloxanthin in a polymethyl-methacrylate matrix varying the
sample temperature. Following photoexcitation, we observe sub-200
fs internal conversion of the bright S2 state into the
lower-lying S1 and S* states, which in turn relax to the
ground state on a picosecond time scale. Upon cooling down the sample
to 77 K, we observe a systematic decrease of the S*/S1 ratio.
This result can be explained by assuming two thermally populated ground
state isomers. The higher lying one generates the S* state, which
can then be effectively frozen out by cooling. These findings are
supported by quantum chemical modeling and provide strong evidence
for the existence and importance of ground state isomers in the photophysics
of carotenoids.
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Affiliation(s)
- J Hauer
- Photonics Institute, Vienna University of Technology, Gusshausstrasse 27, 1040 Vienna, Austria
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39
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Wand A, Gdor I, Zhu J, Sheves M, Ruhman S. Shedding New Light on Retinal Protein Photochemistry. Annu Rev Phys Chem 2013; 64:437-58. [DOI: 10.1146/annurev-physchem-040412-110148] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Amir Wand
- Institute of Chemistry and the Farkas Center for Light-Induced Processes, The Hebrew University of Jerusalem, Jerusalem 91904, Israel;
| | - Itay Gdor
- Institute of Chemistry and the Farkas Center for Light-Induced Processes, The Hebrew University of Jerusalem, Jerusalem 91904, Israel;
| | - Jingyi Zhu
- Institute of Chemistry and the Farkas Center for Light-Induced Processes, The Hebrew University of Jerusalem, Jerusalem 91904, Israel;
| | - Mordechai Sheves
- Department of Organic Chemistry, The Weizmann Institute of Science, Rehovot 76100, Israel
| | - Sanford Ruhman
- Institute of Chemistry and the Farkas Center for Light-Induced Processes, The Hebrew University of Jerusalem, Jerusalem 91904, Israel;
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40
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Christensen RL, Enriquez MM, Wagner NL, Peacock-Villada AY, Scriban C, Schrock RR, Polívka T, Frank HA, Birge RR. Energetics and dynamics of the low-lying electronic states of constrained polyenes: implications for infinite polyenes. J Phys Chem A 2013; 117:1449-65. [PMID: 23330819 DOI: 10.1021/jp310592s] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Steady-state and ultrafast transient absorption spectra were obtained for a series of conformationally constrained, isomerically pure polyenes with 5-23 conjugated double bonds (N). These data and fluorescence spectra of the shorter polyenes reveal the N dependence of the energies of six (1)B(u)(+) and two (1)A(g)(-) excited states. The (1)B(u)(+) states converge to a common infinite polyene limit of 15,900 ± 100 cm(-1). The two excited (1)A(g)(-) states, however, exhibit a large (~9000 cm(-1)) energy difference in the infinite polyene limit, in contrast to the common value previously predicted by theory. EOM-CCSD ab initio and MNDO-PSDCI semiempirical MO theories account for the experimental transition energies and intensities. The complex, multistep dynamics of the 1(1)B(u)(+) → 2(1)A(g)(-) → 1(1)A(g)(-) excited state decay pathways as a function of N are compared with kinetic data from several natural and synthetic carotenoids. Distinctive transient absorption signals in the visible region, previously identified with S* states in carotenoids, also are observed for the longer polyenes. Analysis of the lifetimes of the 2(1)A(g)(-) states, using the energy gap law for nonradiative decay, reveals remarkable similarities in the N dependence of the 2(1)A(g)(-) decay kinetics of the carotenoid and polyene systems. These findings are important for understanding the mechanisms by which carotenoids carry out their roles as light-harvesting molecules and photoprotective agents in biological systems.
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41
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Pillai S, Ravensbergen J, Antoniuk-Pablant A, Sherman BD, van Grondelle R, Frese RN, Moore TA, Gust D, Moore AL, Kennis JTM. Carotenoids as electron or excited-state energy donors in artificial photosynthesis: an ultrafast investigation of a carotenoporphyrin and a carotenofullerene dyad. Phys Chem Chem Phys 2013; 15:4775-84. [DOI: 10.1039/c3cp50364j] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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42
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Vdović S, Wang Y, Li B, Qiu M, Wang X, Guo Q, Xia A. Excited state dynamics of β-carotene studied by means of transient absorption spectroscopy and multivariate curve resolution alternating least-squares analysis. Phys Chem Chem Phys 2013; 15:20026-36. [DOI: 10.1039/c3cp53323a] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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43
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Macernis M, Sulskus J, Duffy CDP, Ruban AV, Valkunas L. Electronic Spectra of Structurally Deformed Lutein. J Phys Chem A 2012; 116:9843-53. [DOI: 10.1021/jp304363q] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Mindaugas Macernis
- Theoretical Physics Department,
Faculty of Physics, Vilnius University,
Saulėtekio al. 9, LT-10222 Vilnius, Lithuania
- Center for Physical Sciences and Technology, Savanorių 231, LT-02300
Vilnius, Lithuania
| | - Juozas Sulskus
- Theoretical Physics Department,
Faculty of Physics, Vilnius University,
Saulėtekio al. 9, LT-10222 Vilnius, Lithuania
| | - Christopher D. P. Duffy
- School
of Biological and Chemical
Sciences, Queen Mary University of London, Mile End Road, London E1 4TN, U.K
| | - Alexander V. Ruban
- School
of Biological and Chemical
Sciences, Queen Mary University of London, Mile End Road, London E1 4TN, U.K
| | - Leonas Valkunas
- Theoretical Physics Department,
Faculty of Physics, Vilnius University,
Saulėtekio al. 9, LT-10222 Vilnius, Lithuania
- Center for Physical Sciences and Technology, Savanorių 231, LT-02300
Vilnius, Lithuania
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44
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Kosumi D, Maruta S, Horibe T, Nagaoka Y, Fujii R, Sugisaki M, Cogdell RJ, Hashimoto H. Ultrafast excited state dynamics of spirilloxanthin in solution and bound to core antenna complexes: Identification of the S* and T1 states. J Chem Phys 2012; 137:064505. [DOI: 10.1063/1.4737129] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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45
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Niedzwiedzki DM, Bina D, Picken N, Honkanen S, Blankenship RE, Holten D, Cogdell RJ. Spectroscopic studies of two spectral variants of light-harvesting complex 2 (LH2) from the photosynthetic purple sulfur bacterium Allochromatium vinosum. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2012; 1817:1576-87. [PMID: 22659401 DOI: 10.1016/j.bbabio.2012.05.009] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/27/2012] [Revised: 05/08/2012] [Accepted: 05/22/2012] [Indexed: 11/17/2022]
Abstract
Two spectral forms of the peripheral light-harvesting complex (LH2) from the purple sulfur photosynthetic bacterium Allochromatium vinosum were purified and their photophysical properties characterized. The complexes contain bacteriochlorophyll a (BChl a) and multiple species of carotenoids. The composition of carotenoids depends on the light conditions applied during growth of the cultures. In addition, LH2 grown under high light has a noticeable split of the B800 absorption band. The influence of the change of carotenoid distribution as well as the spectral change of the excitonic absorption of the bacteriochlorophylls on the light-harvesting ability was studied using steady-state absorption, fluorescence and femtosecond time-resolved absorption at 77K. The results demonstrate that the change of the distribution of the carotenoids when cells were grown at low light adapts the absorptive properties of the complex to the light conditions and maintains maximum photon-capture performance. In addition, an explanation for the origin of the enigmatic split of the B800 absorption band is provided. This spectral splitting is also observed in LH2 complexes from other photosynthetic sulfur purple bacterial species. According to results obtained from transient absorption spectroscopy, the B800 band split originates from two spectral forms of the associated BChl a monomeric molecules bound within the same complex.
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46
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Harvey PD, Stern C, Gros CP, Guilard R. Through space singlet energy transfers in light-harvesting systems and cofacial bisporphyrin dyads. J PORPHYR PHTHALOCYA 2012. [DOI: 10.1142/s1088424610001702] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Recent discoveries from our research groups on the photophysics of a few cofacial bisporphyrin dyads for through space singlet and triplet energy transfers raised several important investigations about the mechanism of energy transfers and energy migration in light-harvesting devices, notably LH II, in the heavily investigated purple photosynthetic bacteria. The key feature is that for face-to-face and slipped dyads with controlled structure using rigid spacers or spacers with limited flexibilities, our fastest rates for singlet energy transfer are in the 10 × 109 s -1 (i.e. 100 ps time scale) for donor-acceptor distances of ~3.5–3.6 Å. The time scale for energy transfers between different bacteriochlorophylls, notably B800*→B850, is in the ps despite the long Mg ⋯ Mg separation (~18 Å). This short rate drastically contrasts with the well-accepted Förster theory. This review focuses on the photophysical processes and dynamics in LH II and compares these parameters with our investigated model dyads build upon octa-etio-porphyrin chromophores and rigid and semi-rigid spacers. The recently discovered role of the rhodopin glucoside (carotenoid) will be analyzed as possible relay for energy transfers, including the possibility of uphill processes at room temperature. In this context the concept of energy migration may be complemented by parallel relays and uphill processes. It is also becoming more obvious that the irreversible electron transfer at the reaction center (electron transfer from the special pair to the phaeophytin) renders the rates for energy transfer and migration faster precluding all possibility of back transfers.
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Affiliation(s)
- Pierre D. Harvey
- Département de Chimie, Université de Sherbrooke, Sherbrooke J1K 2R1, Québec, Canada
| | - Christine Stern
- Institut de Chimie Moléculaire de l'Université de Bourgogne (ICMUB, UMR 5260), 9 Avenue Alain Savary, BP 47870, 21078 Dijon Cedex, France
| | - Claude P. Gros
- Institut de Chimie Moléculaire de l'Université de Bourgogne (ICMUB, UMR 5260), 9 Avenue Alain Savary, BP 47870, 21078 Dijon Cedex, France
| | - Roger Guilard
- Institut de Chimie Moléculaire de l'Université de Bourgogne (ICMUB, UMR 5260), 9 Avenue Alain Savary, BP 47870, 21078 Dijon Cedex, France
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47
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The separation of overlapping transitions in β-carotene with broadband 2D electronic spectroscopy. Chem Phys Lett 2012. [DOI: 10.1016/j.cplett.2011.10.051] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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Niedzwiedzki DM, Fuciman M, Kobayashi M, Frank HA, Blankenship RE. Ultrafast time-resolved spectroscopy of the light-harvesting complex 2 (LH2) from the photosynthetic bacterium Thermochromatium tepidum. PHOTOSYNTHESIS RESEARCH 2011; 110:49-60. [PMID: 21984346 DOI: 10.1007/s11120-011-9692-7] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/14/2011] [Accepted: 09/21/2011] [Indexed: 05/31/2023]
Abstract
The light-harvesting complex 2 from the thermophilic purple bacterium Thermochromatium tepidum was purified and studied by steady-state absorption and fluorescence, sub-nanosecond-time-resolved fluorescence and femtosecond time-resolved transient absorption spectroscopy. The measurements were performed at room temperature and at 10 K. The combination of both ultrafast and steady-state optical spectroscopy methods at ambient and cryogenic temperatures allowed the detailed study of carotenoid (Car)-to-bacteriochlorophyll (BChl) as well BChl-to-BChl excitation energy transfer in the complex. The studies show that the dominant Cars rhodopin (N=11) and spirilloxanthin (N=13) do not play a significant role as supportive energy donors for BChl a. This is related with their photophysical properties regulated by long π-electron conjugation. On the other hand, such properties favor some of the Cars, particularly spirilloxanthin (N=13) to play the role of the direct quencher of the excited singlet state of BChl.
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Affiliation(s)
- Dariusz M Niedzwiedzki
- Photosynthetic Antenna Research Center, Washington University in St. Louis, Campus Box 1138, St. Louis, MO 63130, USA.
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Wang C, Schlamadinger DE, Desai V, Tauber MJ. Triplet excitons of carotenoids formed by singlet fission in a membrane. Chemphyschem 2011; 12:2891-4. [PMID: 21910205 DOI: 10.1002/cphc.201100571] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2011] [Indexed: 11/10/2022]
Affiliation(s)
- Chen Wang
- Department of Chemistry and Biochemistry, University of California at San Diego, 9500 Gilman Drive, La Jolla, CA 92093-0314, USA
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50
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Marek MS, Buckup T, Motzkus M. Direct Observation of a Dark State in Lycopene Using Pump-DFWM. J Phys Chem B 2011; 115:8328-37. [DOI: 10.1021/jp202753j] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Marie S. Marek
- Physikalisch-Chemisches Institut, Ruprecht-Karls-Universität Heidelberg, D-69120 Heidelberg, Germany
| | - Tiago Buckup
- Physikalisch-Chemisches Institut, Ruprecht-Karls-Universität Heidelberg, D-69120 Heidelberg, Germany
| | - Marcus Motzkus
- Physikalisch-Chemisches Institut, Ruprecht-Karls-Universität Heidelberg, D-69120 Heidelberg, Germany
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