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Riedl M, Renger T, Seibt J. Theory of 2D electronic spectroscopy of water soluble chlorophyll-binding protein (WSCP): Signatures of Chl b derivate. J Chem Phys 2024; 160:184114. [PMID: 38726933 DOI: 10.1063/5.0200876] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2024] [Accepted: 04/21/2024] [Indexed: 06/29/2024] Open
Abstract
We investigate how electronic excitations and subsequent dissipative dynamics in the water soluble chlorophyll-binding protein (WSCP) are connected to features in two-dimensional (2D) electronic spectra, thereby comparing results from our theoretical approach with experimental data from the literature. Our calculations rely on third-order response functions, which we derived from a second-order cumulant expansion of the dissipative dynamics involving the partial ordering prescription, assuming a fast vibrational relaxation in the potential energy surfaces of excitons. Depending on whether the WSCP complex containing a tetrameric arrangement of pigments composed of two dimers with weak excitonic coupling between them binds the chlorophyll variant Chl a or Chl b, the resulting linear absorption and circular dichroism spectra and particularly the 2D spectra exhibit substantial differences in line shapes. These differences between Chl a WSCP and Chl b WSCP cannot be explained by the slightly modified excitonic couplings within the two variants. In the case of Chl a WSCP, the assumption of equivalent dimer subunits facilitates a reproduction of substantial features from the experiment by the calculations. In contrast, for Chl b WSCP, we have to assume that the sample, in addition to Chl b dimers, contains a small but distinct fraction of chemically modified Chl b pigments. The existence of such Chl b derivates has been proposed by Pieper et al. [J. Phys. Chem. B 115, 4042 (2011)] based on low-temperature absorption and hole-burning spectroscopy. Here, we provide independent evidence.
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Affiliation(s)
- Michael Riedl
- Institute for Theoretical Physics, Johannes Kepler University Linz, Altenberger Str. 69, 4040 Linz, Austria
| | - Thomas Renger
- Institute for Theoretical Physics, Johannes Kepler University Linz, Altenberger Str. 69, 4040 Linz, Austria
| | - Joachim Seibt
- Institute for Theoretical Physics, Johannes Kepler University Linz, Altenberger Str. 69, 4040 Linz, Austria
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Gisriel CJ, Elias E, Shen G, Soulier NT, Brudvig GW, Croce R, Bryant DA. Structural comparison of allophycocyanin variants reveals the molecular basis for their spectral differences. PHOTOSYNTHESIS RESEARCH 2023:10.1007/s11120-023-01048-4. [PMID: 37773575 DOI: 10.1007/s11120-023-01048-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/22/2023] [Accepted: 09/05/2023] [Indexed: 10/01/2023]
Abstract
Allophycocyanins are phycobiliproteins that absorb red light and transfer the energy to the reaction centers of oxygenic photosynthesis in cyanobacteria and red algae. Recently, it was shown that some allophycocyanins absorb far-red light and that one subset of these allophycocyanins, comprising subunits from the ApcD4 and ApcB3 subfamilies (FRL-AP), form helical nanotubes. The lowest energy absorbance maximum of the oligomeric ApcD4-ApcB3 complexes occurs at 709 nm, which is unlike allophycocyanin (AP; ApcA-ApcB) and allophycocyanin B (AP-B; ApcD-ApcB) trimers that absorb maximally at ~ 650 nm and ~ 670 nm, respectively. The molecular bases of the different spectra of AP variants are presently unclear. To address this, we structurally compared FRL-AP with AP and AP-B, performed spectroscopic analyses on FRL-AP, and leveraged computational approaches. We show that among AP variants, the α-subunit constrains pyrrole ring A of its phycocyanobilin chromophore to different extents, and the coplanarity of ring A with rings B and C sets a baseline for the absorbance maximum of the chromophore. Upon oligomerization, the α-chromophores of all AP variants exhibit a red shift of the absorbance maximum of ~ 25 to 30 nm and band narrowing. We exclude excitonic coupling in FRL-AP as the basis for this red shift and extend the results to discuss AP and AP-B. Instead, we attribute these spectral changes to a conformational alteration of pyrrole ring D, which becomes more coplanar with rings B and C upon oligomerization. This study expands the molecular understanding of light-harvesting attributes of phycobiliproteins and will aid in designing phycobiliproteins for biotechnological applications.
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Affiliation(s)
| | - Eduard Elias
- Department of Physics and Astronomy and Institute for Lasers, Life and Biophotonics, Faculty of Sciences, VU University Amsterdam, 1081 HV, Amsterdam, Netherlands
| | - Gaozhong Shen
- Department of Biochemistry and Molecular Biology, The Pennsylvania State University, University Park, PA, 16802, USA
| | - Nathan T Soulier
- Department of Biochemistry and Molecular Biology, The Pennsylvania State University, University Park, PA, 16802, USA
- Department of Biology, University of California San Diego, La Jolla, CA, 92093, USA
| | - Gary W Brudvig
- Department of Chemistry, Yale University, New Haven, CT, 06520, USA
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT, 06520, USA
| | - Roberta Croce
- Department of Physics and Astronomy and Institute for Lasers, Life and Biophotonics, Faculty of Sciences, VU University Amsterdam, 1081 HV, Amsterdam, Netherlands.
| | - Donald A Bryant
- Department of Biochemistry and Molecular Biology, The Pennsylvania State University, University Park, PA, 16802, USA.
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Fresch E, Collini E. The Role of H-Bonds in the Excited-State Properties of Multichromophoric Systems: Static and Dynamic Aspects. Molecules 2023; 28:molecules28083553. [PMID: 37110786 PMCID: PMC10141795 DOI: 10.3390/molecules28083553] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2023] [Revised: 04/12/2023] [Accepted: 04/15/2023] [Indexed: 04/29/2023] Open
Abstract
Given their importance, hydrogen bonds (H-bonds) have been the subject of intense investigation since their discovery. Indeed, H-bonds play a fundamental role in determining the structure, the electronic properties, and the dynamics of complex systems, including biologically relevant materials such as DNA and proteins. While H-bonds have been largely investigated for systems in their electronic ground state, fewer studies have focused on how the presence of H-bonds could affect the static and dynamic properties of electronic excited states. This review presents an overview of the more relevant progress in studying the role of H-bond interactions in modulating excited-state features in multichromophoric biomimetic complex systems. The most promising spectroscopic techniques that can be used for investigating the H-bond effects in excited states and for characterizing the ultrafast processes associated with their dynamics are briefly summarized. Then, experimental insights into the modulation of the electronic properties resulting from the presence of H-bond interactions are provided, and the role of the H-bond in tuning the excited-state dynamics and the related photophysical processes is discussed.
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Affiliation(s)
- Elisa Fresch
- Department of Chemical Sciences, University of Padova, Via Marzolo 1, 35131 Padova, Italy
| | - Elisabetta Collini
- Department of Chemical Sciences, University of Padova, Via Marzolo 1, 35131 Padova, Italy
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Abstract
Biological pigment-protein complexes (PPCs) exhibit a remarkable ability to tune the optical properties of biological excitons (bioexcitons) through specific pigment-protein interactions. While such fine-tuning allows natural systems (e.g., photosynthetic proteins) to carry out their native functions with near-optimal performance, native function itself is often suboptimal for applications such as biofuel production or quantum technology development. This perspective offers a look at near-term prospects for the rational reoptimization of PPC bioexcitons for new functions using site-directed mutagenesis. The primary focus is on the "structure-spectrum" challenge of understanding the relationships between structural features and spectroscopic properties. While recent examples demonstrate that site-directed mutagenesis can be used to tune nearly all key bioexciton parameters (e.g., site energies, interpigment couplings, and electronic-vibrational interactions), critical challenges remain before we achieve truly rational design of bioexciton properties.
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Affiliation(s)
- Mike Reppert
- Department of Chemistry, Purdue University, West Lafayette, Indiana 47907, United States
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Gisriel CJ, Shen G, Flesher DA, Kurashov V, Golbeck JH, Brudvig GW, Amin M, Bryant DA. Structure of a dimeric photosystem II complex from a cyanobacterium acclimated to far-red light. J Biol Chem 2022; 299:102815. [PMID: 36549647 PMCID: PMC9843442 DOI: 10.1016/j.jbc.2022.102815] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2022] [Revised: 12/12/2022] [Accepted: 12/13/2022] [Indexed: 12/24/2022] Open
Abstract
Photosystem II (PSII) is the water-splitting enzyme central to oxygenic photosynthesis. To drive water oxidation, light is harvested by accessory pigments, mostly chlorophyll (Chl) a molecules, which absorb visible light (400-700 nm). Some cyanobacteria facultatively acclimate to shaded environments by altering their photosynthetic machinery to additionally absorb far-red light (FRL, 700-800 nm), a process termed far-red light photoacclimation or FaRLiP. During far-red light photoacclimation, FRL-PSII is assembled with FRL-specific isoforms of the subunits PsbA, PsbB, PsbC, PsbD, and PsbH, and some Chl-binding sites contain Chls d or f instead of the usual Chl a. The structure of an apo-FRL-PSII monomer lacking the FRL-specific PsbH subunit has previously been determined, but visualization of the dimeric complex has remained elusive. Here, we report the cryo-EM structure of a dimeric FRL-PSII complex. The site assignments for Chls d and f are consistent with those assigned in the previous apo-FRL-PSII monomeric structure. All sites that bind Chl d or Chl f at high occupancy exhibit a FRL-specific interaction of the formyl moiety of the Chl d or Chl f with the protein environment, which in some cases involves a phenylalanine sidechain. The structure retains the FRL-specific PsbH2 subunit, which appears to alter the energetic landscape of FRL-PSII, redirecting energy transfer from the phycobiliprotein complex to a Chl f molecule bound by PsbB2 that acts as a bridge for energy transfer to the electron transfer chain. Collectively, these observations extend our previous understanding of the structure-function relationship that allows PSII to function using lower energy FRL.
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Affiliation(s)
- Christopher J. Gisriel
- Department of Chemistry, Yale University, New Haven, Connecticut, USA,For correspondence: Christopher J. Gisriel; Donald A. Bryant
| | - Gaozhong Shen
- Department of Biochemistry and Molecular Biology, The Pennsylvania State University, University Park, Pennsylvania, USA
| | - David A. Flesher
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, Connecticut, USA
| | - Vasily Kurashov
- Department of Biochemistry and Molecular Biology, The Pennsylvania State University, University Park, Pennsylvania, USA
| | - John H. Golbeck
- Department of Biochemistry and Molecular Biology, The Pennsylvania State University, University Park, Pennsylvania, USA,Department of Chemistry, The Pennsylvania State University, University Park, Pennsylvania, USA
| | - Gary W. Brudvig
- Department of Chemistry, Yale University, New Haven, Connecticut, USA,Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, Connecticut, USA
| | - Muhamed Amin
- Department of Sciences, University College Groningen, University of Groningen, Groningen, the Netherlands,Rijksuniversiteit Groningen Biomolecular Sciences and Biotechnology Institute, University of Groningen, Groningen, the Netherlands,Center for Free-Electron Laser Science, Deutsches Elektronen-Synchrotron DESY, Hamburg, Germany
| | - Donald A. Bryant
- Department of Biochemistry and Molecular Biology, The Pennsylvania State University, University Park, Pennsylvania, USA,For correspondence: Christopher J. Gisriel; Donald A. Bryant
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Mondragón-Solórzano G, Sandoval-Lira J, Nochebuena J, Cisneros GA, Barroso-Flores J. Electronic Structure Effects Related to the Origin of the Remarkable Near-Infrared Absorption of Blastochloris viridis' Light Harvesting 1-Reaction Center Complex. J Chem Theory Comput 2022; 18:4555-4564. [PMID: 35767461 PMCID: PMC10408377 DOI: 10.1021/acs.jctc.2c00497] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Various photosynthetic organisms have evolved to absorb light in different regions of the visible light spectrum, thus adapting to the various lighting conditions available on Earth. While most of these autotrophic organisms absorb wavelengths around the 700-800 nm region, some are capable of red-shifted absorptions above this range, but none as remarkably as Blastochloris viridis whose main absorption is observed at 1015 nm, approximately 220 nm (0.34 eV) lower in energy than their main constituent pigments, BChl-b, whose main absorption is observed at 795 nm. The structure of its light harvesting 1-reaction center was recently elucidated by cryo-EM; however, the electronic structure details behind this red-shifted absorption remain unattended. We used hybrid quantum mechanics/molecular mechanics (QM/MM) calculations to optimize one of the active centers and performed classical molecular dynamics (MD) simulations to sample conformations beyond the optimized structure. We did excited state calculations with the time-dependent density functional theory method at the CAM-B3LYP/cc-pVDZ level of theory. We reproduced the near IR absorption by sequentially modifying the number of components involved in our systems using representative structures from the calculated MD ensemble. Natural transition orbital analysis reveals the participation of the BChl-b fragments to the main transition in the native structure and the structures obtained from the QM/MM and MD simulations. H-bonding pigment-protein interactions play a role on the conformation stabilization and orientation; however, the bacteriochlorin ring conformations and the exciton delocalization are the most relevant factors to explain the red-shifting phenomenon.
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Affiliation(s)
- Gustavo Mondragón-Solórzano
- Centro Conjunto de Investigación en Química Sustentable UAEM-UNAM. Carretera Toluca-Atlacomulco Km. 14.5, Unidad San Cayetano. Toluca de Lerdo 50200, México
- Instituto de Química. Universidad Nacional Autónoma de México, Circuito Exterior, Ciudad Universitaria, CDMX 04510, México
| | - Jacinto Sandoval-Lira
- Centro Conjunto de Investigación en Química Sustentable UAEM-UNAM. Carretera Toluca-Atlacomulco Km. 14.5, Unidad San Cayetano. Toluca de Lerdo 50200, México
- Instituto de Química. Universidad Nacional Autónoma de México, Circuito Exterior, Ciudad Universitaria, CDMX 04510, México
- Departamento de Ingeniería Ambiental, Instituto Tecnológico Superior de San Martín Texmelucan, TecNM, Camino a la Barranca de Pesos, C.P. 74120 San Martín Texmelucan, Puebla, México
| | - Jorge Nochebuena
- Department of Physics, University of Texas at Dallas, Richardson, Texas 75801, United States
| | - G Andrés Cisneros
- Department of Physics, University of Texas at Dallas, Richardson, Texas 75801, United States
- Department of Chemistry and Biochemistry, University of Texas at Dallas, Richardson, Texas 75801, United States
| | - Joaquín Barroso-Flores
- Centro Conjunto de Investigación en Química Sustentable UAEM-UNAM. Carretera Toluca-Atlacomulco Km. 14.5, Unidad San Cayetano. Toluca de Lerdo 50200, México
- Instituto de Química. Universidad Nacional Autónoma de México, Circuito Exterior, Ciudad Universitaria, CDMX 04510, México
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Gisriel CJ, Cardona T, Bryant DA, Brudvig GW. Molecular Evolution of Far-Red Light-Acclimated Photosystem II. Microorganisms 2022; 10:1270. [PMID: 35888987 PMCID: PMC9325196 DOI: 10.3390/microorganisms10071270] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2022] [Revised: 06/17/2022] [Accepted: 06/18/2022] [Indexed: 12/10/2022] Open
Abstract
Cyanobacteria are major contributors to global carbon fixation and primarily use visible light (400-700 nm) to drive oxygenic photosynthesis. When shifted into environments where visible light is attenuated, a small, but highly diverse and widespread number of cyanobacteria can express modified pigments and paralogous versions of photosystem subunits and phycobiliproteins that confer far-red light (FRL) absorbance (700-800 nm), a process termed far-red light photoacclimation, or FaRLiP. During FaRLiP, alternate photosystem II (PSII) subunits enable the complex to bind chlorophylls d and f, which absorb at lower energy than chlorophyll a but still support water oxidation. How the FaRLiP response arose remains poorly studied. Here, we report ancestral sequence reconstruction and structure-based molecular evolutionary studies of the FRL-specific subunits of FRL-PSII. We show that the duplications leading to the origin of two PsbA (D1) paralogs required to make chlorophyll f and to bind chlorophyll d in water-splitting FRL-PSII are likely the first to have occurred prior to the diversification of extant cyanobacteria. These duplications were followed by those leading to alternative PsbC (CP43) and PsbD (D2) subunits, occurring early during the diversification of cyanobacteria, and culminating with those leading to PsbB (CP47) and PsbH paralogs coincident with the radiation of the major groups. We show that the origin of FRL-PSII required the accumulation of a relatively small number of amino acid changes and that the ancestral FRL-PSII likely contained a chlorophyll d molecule in the electron transfer chain, two chlorophyll f molecules in the antenna subunits at equivalent positions, and three chlorophyll a molecules whose site energies were altered. The results suggest a minimal model for engineering far-red light absorbance into plant PSII for biotechnological applications.
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Affiliation(s)
| | - Tanai Cardona
- Department of Life Sciences, Imperial College London, London SW7 2AZ, UK;
| | - Donald A. Bryant
- Department of Biochemistry and Molecular Biology, The Pennsylvania State University, University Park, PA 16802, USA;
| | - Gary W. Brudvig
- Department of Chemistry, Yale University, New Haven, CT 06520, USA;
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT 06520, USA
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8
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Takeda T, Kitagawa Y, Tamiaki H. Substituted Methylenation at the 13 2 -Position of a Chlorophyll-a Derivative via Mixed Aldol Condensation, Optical Properties of the Synthetic Bacteriochlorophyll-d Analogs, and Self-aggregation of Their Zinc Complexes. Photochem Photobiol 2022; 98:1059-1067. [PMID: 35119101 DOI: 10.1111/php.13604] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2021] [Revised: 01/25/2022] [Accepted: 01/26/2022] [Indexed: 11/30/2022]
Abstract
Chlorophyll-a derivatives possessing a substituted methylene group at the 132 -position were prepared by the mixed aldol condensation of methyl 3-hydroxymethyl-pyropheophorbide-a with aldehydes bearing a methyl, p-nitro/cyanophenyl, or pentafluorophenyl group. Their electronic absorption spectra were dependent on the substituents at the methylene terminal. The Soret bands were broadened with increasing the group electronegativity of the substituents, which was ascribable to the charge transfer from the core chlorin to the peripheral substituent in a molecule. Although their Qy absorption and fluorescence emission bands resembled each other, the emission intensities decreased with an increase in the electronegativity because of the intramolecular electron transfer quenching. Some of their zinc complexes self-aggregated in a less polar organic solvent to give red-shifted and broadened absorption bands with intense circular dichroism couplets, which were similar to those of bacteriochlorophyll-c/d aggregates in natural chlorosomes as the main light-harvesting antennas of green photosynthetic bacteria and their models. The J-aggregation was suppressed with an enhancement in the size of the 132 -substituents.
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Affiliation(s)
- Toyoho Takeda
- Graduate School of Life Sciences, Ritsumeikan University, Kusatsu, Shiga, 525-8577, Japan
| | - Yuichi Kitagawa
- Division of Materials Chemistry, Faculty of Engineering, Hokkaido University, Sapporo Hokkaido, Japan
| | - Hitoshi Tamiaki
- Graduate School of Life Sciences, Ritsumeikan University, Kusatsu, Shiga, 525-8577, Japan
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Sirohiwal A, Pantazis DA. Electrostatic profiling of photosynthetic pigments: implications for directed spectral tuning. Phys Chem Chem Phys 2021; 23:24677-24684. [PMID: 34708851 DOI: 10.1039/d1cp02580e] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Photosynthetic pigment-protein complexes harvest solar energy with a high quantum efficiency. Protein scaffolds are known to tune the spectral properties of embedded pigments principally through structured electrostatic environments. Although the physical nature of electrostatic tuning is straightforward, the precise spatial principles of electrostatic preorganization remain poorly explored for different protein matrices and incompletely characterized with respect to the intrinsic properties of different photosynthetic pigments. In this work, we study the electronic structure features associated with the lowest excited state of a series of eight naturally occurring (bacterio)chlorophylls and pheophytins to describe the precise topological differences in electrostatic potentials and hence determine intrinsic differences in the expected mode and impact of electrostatic tuning. The difference electrostatic potentials between the ground and first excited states are used as fingerprints. Both the spatial profile and the propensity for spectral tuning are found to be unique for each pigment, indicating spatially and directionally distinct modes of electrostatic tuning. The results define a specific partitioning of the protein matrix around each pigment as an aid to identify regions with a maximal impact on spectral tuning and have direct implications for dimensionality reduction in protein design and engineering. Thus, a quantum mechanical basis is provided for understanding, predicting, and ultimately designing sequence-modified or pigment-exchanged biological systems, as suggested for selected examples of pigment-reconstituted proteins.
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Affiliation(s)
- Abhishek Sirohiwal
- Max-Planck-Institut für Kohlenforschung, Kaiser-Wilhelm-Platz 1, 45470 Mülheim an der Ruhr, Germany.
| | - Dimitrios A Pantazis
- Max-Planck-Institut für Kohlenforschung, Kaiser-Wilhelm-Platz 1, 45470 Mülheim an der Ruhr, Germany.
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10
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Antipin IS, Alfimov MV, Arslanov VV, Burilov VA, Vatsadze SZ, Voloshin YZ, Volcho KP, Gorbatchuk VV, Gorbunova YG, Gromov SP, Dudkin SV, Zaitsev SY, Zakharova LY, Ziganshin MA, Zolotukhina AV, Kalinina MA, Karakhanov EA, Kashapov RR, Koifman OI, Konovalov AI, Korenev VS, Maksimov AL, Mamardashvili NZ, Mamardashvili GM, Martynov AG, Mustafina AR, Nugmanov RI, Ovsyannikov AS, Padnya PL, Potapov AS, Selektor SL, Sokolov MN, Solovieva SE, Stoikov II, Stuzhin PA, Suslov EV, Ushakov EN, Fedin VP, Fedorenko SV, Fedorova OA, Fedorov YV, Chvalun SN, Tsivadze AY, Shtykov SN, Shurpik DN, Shcherbina MA, Yakimova LS. Functional supramolecular systems: design and applications. RUSSIAN CHEMICAL REVIEWS 2021. [DOI: 10.1070/rcr5011] [Citation(s) in RCA: 52] [Impact Index Per Article: 17.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
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11
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Saga Y, Tanaka A, Yamashita M, Shinoda T, Tomo T, Kimura Y. Spectral Properties of Chlorophyll f in the B800 Cavity of Light-harvesting Complex 2 from the Purple Photosynthetic Bacterium Rhodoblastus acidophilus. Photochem Photobiol 2021; 98:169-174. [PMID: 34293183 DOI: 10.1111/php.13491] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2021] [Revised: 07/20/2021] [Accepted: 07/21/2021] [Indexed: 11/29/2022]
Abstract
The interactions of chlorophyll (Chl) and bacteriochlorophyll (BChl) pigments with the polypeptides in photosynthetic light-harvesting proteins are responsible for controlling the absorption energy of (B)Chls in protein matrixes. The binding pocket of B800 BChl a in LH2 proteins, which are peripheral light-harvesting proteins in purple photosynthetic bacteria, is useful for studying such structure-property relationships. We report the reconstitution of Chl f, which has the formyl group at the 2-position, in the B800 cavity of LH2 from the purple bacterium Rhodoblastus acidophilus. The Qy absorption band of Chl f in the B800 cavity was shifted by 14 nm to longer wavelength compared to that of the corresponding five-coordinated monomer in acetone. This redshift was larger than that of Chl a and Chl b. Resonance Raman spectroscopy indicated hydrogen bonding between the 2-formyl group of Chl f and the LH2 polypeptide. These results suggest that this hydrogen bonding contributes to the Qy redshift of Chl f. Furthermore, the Qy redshift of Chl f in the B800 cavity was smaller than that of Chl d. This may have arisen from the different patterns of hydrogen bonding between Chl f and Chl d and/or from the steric hindrance of the 3-vinyl group in Chl f.
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Affiliation(s)
- Yoshitaka Saga
- Department of Chemistry, Faculty of Science and Engineering, Kindai University, Osaka, Japan
| | - Aiko Tanaka
- Department of Chemistry, Faculty of Science and Engineering, Kindai University, Osaka, Japan
| | - Madoka Yamashita
- Department of Chemistry, Faculty of Science and Engineering, Kindai University, Osaka, Japan
| | - Toshiyuki Shinoda
- Graduate School of Science, Tokyo University of Science, Tokyo, Japan
| | - Tatsuya Tomo
- Graduate School of Science, Tokyo University of Science, Tokyo, Japan
| | - Yukihiro Kimura
- Graduate School of Agricultural Science, Kobe University, Kobe, Japan
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12
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Fresch E, Peruffo N, Trapani M, Cordaro M, Bella G, Castriciano MA, Collini E. The effect of hydrogen bonds on the ultrafast relaxation dynamics of a BODIPY dimer. J Chem Phys 2021; 154:084201. [PMID: 33639732 DOI: 10.1063/5.0038242] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
The influence of hydrogen bonds (H-bonds) in the structure, dynamics, and functionality of biological and artificial complex systems is the subject of intense investigation. In this broad context, particular attention has recently been focused on the ultrafast H-bond dependent dynamical properties in the electronic excited state because of their potentially dramatic consequences on the mechanism, dynamics, and efficiency of photochemical reactions and photophysical processes of crucial importance for life and technology. Excited-state H-bond dynamics generally occur on ultrafast time scales of hundreds of femtoseconds or less, making the characterization of associated mechanisms particularly challenging with conventional time-resolved techniques. Here, 2D electronic spectroscopy is exploited to shed light on this still largely unexplored dynamic mechanism. An H-bonded molecular dimer prepared by self-assembly of two boron-dipyrromethene dyes has been specifically designed and synthesized for this aim. The obtained results confirm that upon formation of H-bonds and the dimer, a new ultrafast relaxation channel is activated in the ultrafast dynamics, mediated by the vibrational motions of the hydrogen donor and acceptor groups. This relaxation channel also involves, beyond intra-molecular relaxations, an inter-molecular transfer process. This is particularly significant considering the long distance between the centers of mass of the two molecules. These findings suggest that the design of H-bonded structures is a particularly powerful tool to drive the ultrafast dynamics in complex materials.
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Affiliation(s)
- Elisa Fresch
- Dipartimento di Scienze Chimiche, Università di Padova, via Marzolo 1, 35131 Padova, Italy
| | - Nicola Peruffo
- Dipartimento di Scienze Chimiche, Università di Padova, via Marzolo 1, 35131 Padova, Italy
| | - Mariachiara Trapani
- CNR-ISMN, Istituto per lo Studio dei Materiali Nanostrutturati, c/o Dipartimento di Scienze Chimiche, Biologiche, Farmaceutiche ed Ambientali, V.le F. Stagno D'Alcontres 31, 98166 Messina, Italy
| | - Massimiliano Cordaro
- Dipartimento di Scienze Chimiche, Biologiche, Farmaceutiche ed Ambientali, Università di Messina, V.le F. Stagno D'Alcontres 31, 98166 Messina, Italy
| | - Giovanni Bella
- Dipartimento di Scienze Chimiche, Biologiche, Farmaceutiche ed Ambientali, Università di Messina, V.le F. Stagno D'Alcontres 31, 98166 Messina, Italy
| | - Maria Angela Castriciano
- CNR-ISMN, Istituto per lo Studio dei Materiali Nanostrutturati, c/o Dipartimento di Scienze Chimiche, Biologiche, Farmaceutiche ed Ambientali, V.le F. Stagno D'Alcontres 31, 98166 Messina, Italy
| | - Elisabetta Collini
- Dipartimento di Scienze Chimiche, Università di Padova, via Marzolo 1, 35131 Padova, Italy
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Slattery RA, Ort DR. Perspectives on improving light distribution and light use efficiency in crop canopies. PLANT PHYSIOLOGY 2021; 185:34-48. [PMID: 33631812 PMCID: PMC8133579 DOI: 10.1093/plphys/kiaa006] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/14/2020] [Accepted: 10/03/2020] [Indexed: 05/22/2023]
Abstract
Plant stands in nature differ markedly from most seen in modern agriculture. In a dense mixed stand, plants must vie for resources, including light, for greater survival and fitness. Competitive advantages over surrounding plants improve fitness of the individual, thus maintaining the competitive traits in the gene pool. In contrast, monoculture crop production strives to increase output at the stand level and thus benefits from cooperation to increase yield of the community. In choosing plants with higher yields to propagate and grow for food, humans may have inadvertently selected the best competitors rather than the best cooperators. Here, we discuss how this selection for competitiveness has led to overinvestment in characteristics that increase light interception and, consequently, sub-optimal light use efficiency in crop fields that constrains yield improvement. Decades of crop canopy modeling research have provided potential strategies for improving light distribution in crop canopies, and we review the current progress of these strategies, including balancing light distribution through reducing pigment concentration. Based on recent research revealing red-shifted photosynthetic pigments in algae and photosynthetic bacteria, we also discuss potential strategies for optimizing light interception and use through introducing alternative pigment types in crops. These strategies for improving light distribution and expanding the wavelengths of light beyond those traditionally defined for photosynthesis in plant canopies may have large implications for improving crop yield and closing the yield gap.
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Affiliation(s)
- Rebecca A Slattery
- Carl R. Woese Institute for Genomic Biology, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, USA
| | - Donald R Ort
- Carl R. Woese Institute for Genomic Biology, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, USA
- Departments of Plant Biology & Crop Sciences, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, USA
- Author for communication:
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14
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Li F, Liu C, Streckaite S, Yang C, Xu P, Llansola-Portoles MJ, Ilioaia C, Pascal AA, Croce R, Robert B. A new, unquenched intermediate of LHCII. J Biol Chem 2021; 296:100322. [PMID: 33493515 PMCID: PMC7949128 DOI: 10.1016/j.jbc.2021.100322] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2020] [Revised: 01/18/2021] [Accepted: 01/20/2021] [Indexed: 11/23/2022] Open
Abstract
When plants are exposed to high-light conditions, the potentially harmful excess energy is dissipated as heat, a process called non-photochemical quenching. Efficient energy dissipation can also be induced in the major light-harvesting complex of photosystem II (LHCII) in vitro, by altering the structure and interactions of several bound cofactors. In both cases, the extent of quenching has been correlated with conformational changes (twisting) affecting two bound carotenoids, neoxanthin, and one of the two luteins (in site L1). This lutein is directly involved in the quenching process, whereas neoxanthin senses the overall change in state without playing a direct role in energy dissipation. Here we describe the isolation of an intermediate state of LHCII, using the detergent n-dodecyl-α-D-maltoside, which exhibits the twisting of neoxanthin (along with changes in chlorophyll–protein interactions), in the absence of the L1 change or corresponding quenching. We demonstrate that neoxanthin is actually a reporter of the LHCII environment—probably reflecting a large-scale conformational change in the protein—whereas the appearance of excitation energy quenching is concomitant with the configuration change of the L1 carotenoid only, reflecting changes on a smaller scale. This unquenched LHCII intermediate, described here for the first time, provides for a deeper understanding of the molecular mechanism of quenching.
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Affiliation(s)
- Fei Li
- Key Laboratory of Plant Resources, Institute of Botany, Chinese Academy of Sciences, Beijing, China
| | - Cheng Liu
- Key Laboratory of Plant Resources, Institute of Botany, Chinese Academy of Sciences, Beijing, China
| | - Simona Streckaite
- Université Paris-Saclay, CEA, CNRS, Institute for Integrative Biology of the Cell (I2BC), Gif-sur-Yvette, France
| | - Chunhong Yang
- Key Laboratory of Plant Resources, Institute of Botany, Chinese Academy of Sciences, Beijing, China
| | - Pengqi Xu
- Department of Physics and Astronomy, Faculty of Sciences, VU University Amsterdam, Amsterdam, The Netherlands
| | - Manuel J Llansola-Portoles
- Université Paris-Saclay, CEA, CNRS, Institute for Integrative Biology of the Cell (I2BC), Gif-sur-Yvette, France
| | - Cristian Ilioaia
- Université Paris-Saclay, CEA, CNRS, Institute for Integrative Biology of the Cell (I2BC), Gif-sur-Yvette, France.
| | - Andrew A Pascal
- Université Paris-Saclay, CEA, CNRS, Institute for Integrative Biology of the Cell (I2BC), Gif-sur-Yvette, France
| | - Roberta Croce
- Department of Physics and Astronomy, Faculty of Sciences, VU University Amsterdam, Amsterdam, The Netherlands
| | - Bruno Robert
- Université Paris-Saclay, CEA, CNRS, Institute for Integrative Biology of the Cell (I2BC), Gif-sur-Yvette, France.
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15
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Sirohiwal A, Neese F, Pantazis DA. Protein Matrix Control of Reaction Center Excitation in Photosystem II. J Am Chem Soc 2020; 142:18174-18190. [PMID: 33034453 PMCID: PMC7582616 DOI: 10.1021/jacs.0c08526] [Citation(s) in RCA: 40] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2020] [Indexed: 02/06/2023]
Abstract
Photosystem II (PSII) is a multisubunit pigment-protein complex that uses light-induced charge separation to power oxygenic photosynthesis. Its reaction center chromophores, where the charge transfer cascade is initiated, are arranged symmetrically along the D1 and D2 core polypeptides and comprise four chlorophyll (PD1, PD2, ChlD1, ChlD2) and two pheophytin molecules (PheoD1 and PheoD2). Evolution favored productive electron transfer only via the D1 branch, with the precise nature of primary excitation and the factors that control asymmetric charge transfer remaining under investigation. Here we present a detailed atomistic description for both. We combine large-scale simulations of membrane-embedded PSII with high-level quantum-mechanics/molecular-mechanics (QM/MM) calculations of individual and coupled reaction center chromophores to describe reaction center excited states. We employ both range-separated time-dependent density functional theory and the recently developed domain based local pair natural orbital (DLPNO) implementation of the similarity transformed equation of motion coupled cluster theory with single and double excitations (STEOM-CCSD), the first coupled cluster QM/MM calculations of the reaction center. We find that the protein matrix is exclusively responsible for both transverse (chlorophylls versus pheophytins) and lateral (D1 versus D2 branch) excitation asymmetry, making ChlD1 the chromophore with the lowest site energy. Multipigment calculations show that the protein matrix renders the ChlD1 → PheoD1 charge-transfer the lowest energy excitation globally within the reaction center, lower than any pigment-centered local excitation. Remarkably, no low-energy charge transfer states are located within the "special pair" PD1-PD2, which is therefore excluded as the site of initial charge separation in PSII. Finally, molecular dynamics simulations suggest that modulation of the electrostatic environment due to protein conformational flexibility enables direct excitation of low-lying charge transfer states by far-red light.
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Affiliation(s)
- Abhishek Sirohiwal
- Max-Planck-Institut
für Kohlenforschung, Kaiser-Wilhelm-Platz 1, 45470 Mülheim an der Ruhr, Germany
- Fakultät
für Chemie und Biochemie, Ruhr-Universität
Bochum, 44780 Bochum, Germany
| | - Frank Neese
- Max-Planck-Institut
für Kohlenforschung, Kaiser-Wilhelm-Platz 1, 45470 Mülheim an der Ruhr, Germany
| | - Dimitrios A. Pantazis
- Max-Planck-Institut
für Kohlenforschung, Kaiser-Wilhelm-Platz 1, 45470 Mülheim an der Ruhr, Germany
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16
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Saccon F, Durchan M, Polívka T, Ruban AV. The robustness of the terminal emitter site in major LHCII complexes controls xanthophyll function during photoprotection. Photochem Photobiol Sci 2020; 19:1308-1318. [PMID: 32815966 DOI: 10.1039/d0pp00174k] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Xanthophylls in light harvesting complexes perform a number of functions ranging from structural support to light-harvesting and photoprotection. In the major light harvesting complex of photosystem II in plants (LHCII), the innermost xanthophyll binding pockets are occupied by lutein molecules. The conservation of these sites within the LHC protein family suggests their importance in LHCII functionality. In the present work, we induced the photoprotective switch in LHCII isolated from the Arabidopsis mutant npq1lut2, where the lutein molecules are exchanged with violaxanthin. Despite the differences in the energetics of the pigments and the impairment of chlorophyll fluorescence quenching in vivo, we show that isolated complexes containing violaxanthin are still able to induce the quenching switch to a similar extent to wild type LHCII monomers. Moreover, the same spectroscopic changes take place, which suggest the involvement of the terminal emitter site (L1) in energy dissipation in both complexes. These results indicate the robust nature of the L1 xanthophyll binding domain in LHCII, where protein structural cues are the major determinant of the function of the bound carotenoid.
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Affiliation(s)
- Francesco Saccon
- Queen Mary University of London, School of Biological and Chemical Sciences, Mile End Road E1 4NS, London, UK.
| | - Milan Durchan
- University of South Bohemia, Institute of Physics, Faculty of Science, České Budějovice, Czech Republic
| | - Tomáš Polívka
- University of South Bohemia, Institute of Physics, Faculty of Science, České Budějovice, Czech Republic
| | - Alexander V Ruban
- Queen Mary University of London, School of Biological and Chemical Sciences, Mile End Road E1 4NS, London, UK.
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17
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Sirohiwal A, Berraud-Pache R, Neese F, Izsák R, Pantazis DA. Accurate Computation of the Absorption Spectrum of Chlorophyll a with Pair Natural Orbital Coupled Cluster Methods. J Phys Chem B 2020; 124:8761-8771. [PMID: 32930590 PMCID: PMC7584356 DOI: 10.1021/acs.jpcb.0c05761] [Citation(s) in RCA: 55] [Impact Index Per Article: 13.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
![]()
The
ability to accurately compute low-energy excited states of
chlorophylls is critically important for understanding the vital roles
they play in light harvesting, energy transfer, and photosynthetic
charge separation. The challenge for quantum chemical methods arises
both from the intrinsic complexity of the electronic structure problem
and, in the case of biological models, from the need to account for
protein–pigment interactions. In this work, we report electronic
structure calculations of unprecedented accuracy for the low-energy
excited states in the Q and B bands of chlorophyll a. This is achieved by using the newly developed domain-based local
pair natural orbital (DLPNO) implementation of the similarity transformed
equation of motion coupled cluster theory with single and double excitations
(STEOM-CCSD) in combination with sufficiently large and flexible basis
sets. The results of our DLPNO–STEOM-CCSD calculations are
compared with more approximate approaches. The results demonstrate
that, in contrast to time-dependent density functional theory, the
DLPNO–STEOM-CCSD method provides a balanced performance for
both absorption bands. In addition to vertical excitation energies,
we have calculated the vibronic spectrum for the Q and B bands through
a combination of DLPNO–STEOM-CCSD and ground-state density
functional theory frequency calculations. These results serve as a
basis for comparison with gas-phase experiments.
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Affiliation(s)
- Abhishek Sirohiwal
- Max-Planck-Institut für Kohlenforschung, Kaiser-Wilhelm-Platz 1, 45470 Mülheim an der Ruhr, Germany.,Fakultät für Chemie und Biochemie, Ruhr-Universität Bochum, 44780 Bochum, Germany
| | - Romain Berraud-Pache
- Max-Planck-Institut für Kohlenforschung, Kaiser-Wilhelm-Platz 1, 45470 Mülheim an der Ruhr, Germany
| | - Frank Neese
- Max-Planck-Institut für Kohlenforschung, Kaiser-Wilhelm-Platz 1, 45470 Mülheim an der Ruhr, Germany
| | - Róbert Izsák
- Max-Planck-Institut für Kohlenforschung, Kaiser-Wilhelm-Platz 1, 45470 Mülheim an der Ruhr, Germany
| | - Dimitrios A Pantazis
- Max-Planck-Institut für Kohlenforschung, Kaiser-Wilhelm-Platz 1, 45470 Mülheim an der Ruhr, Germany
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18
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Fresch E, Meneghin E, Agostini A, Paulsen H, Carbonera D, Collini E. How the Protein Environment Can Tune the Energy, the Coupling, and the Ultrafast Dynamics of Interacting Chlorophylls: The Example of the Water-Soluble Chlorophyll Protein. J Phys Chem Lett 2020; 11:1059-1067. [PMID: 31952446 PMCID: PMC7995254 DOI: 10.1021/acs.jpclett.9b03628] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/14/2023]
Abstract
The interplay between active molecules and the protein environment in light-harvesting complexes tunes the photophysics and the dynamical properties of pigment-protein complexes in a subtle way, which is not fully understood. Here we characterized the photophysics and the ultrafast dynamics of four variants of the water-soluble chlorophyll protein (WSCP) as an ideal model system to study the behavior of strongly interacting chlorophylls. We found that when coordinated by the WSCP protein, the presence of the formyl group in chlorophyll b replacing the methyl group in chlorophyll a strongly affects the exciton energy and the dynamics of the system, opening up the possibility of tuning the photophysics and the transport properties of multichromophores by engineering specific interactions with the surroundings.
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Affiliation(s)
- Elisa Fresch
- Department
of Chemical Sciences, University of Padova, via Marzolo 1, 35131 Padua, Italy
| | - Elena Meneghin
- Department
of Chemical Sciences, University of Padova, via Marzolo 1, 35131 Padua, Italy
| | - Alessandro Agostini
- Department
of Chemical Sciences, University of Padova, via Marzolo 1, 35131 Padua, Italy
- Institute
of Molecular Physiology, Johannes Gutenberg-University, Johannes-von-Müller-Weg 6, 55128 Mainz, Germany
| | - Harald Paulsen
- Institute
of Molecular Physiology, Johannes Gutenberg-University, Johannes-von-Müller-Weg 6, 55128 Mainz, Germany
| | - Donatella Carbonera
- Department
of Chemical Sciences, University of Padova, via Marzolo 1, 35131 Padua, Italy
| | - Elisabetta Collini
- Department
of Chemical Sciences, University of Padova, via Marzolo 1, 35131 Padua, Italy
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19
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Agostini A, Meneghin E, Gewehr L, Pedron D, Palm DM, Carbonera D, Paulsen H, Jaenicke E, Collini E. How water-mediated hydrogen bonds affect chlorophyll a/b selectivity in Water-Soluble Chlorophyll Protein. Sci Rep 2019; 9:18255. [PMID: 31796824 PMCID: PMC6890793 DOI: 10.1038/s41598-019-54520-4] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2019] [Accepted: 11/14/2019] [Indexed: 01/15/2023] Open
Abstract
The Water-Soluble Chlorophyll Protein (WSCP) of Brassicaceae is a remarkably stable tetrapyrrole-binding protein that, by virtue of its simple design, is an exceptional model to investigate the interactions taking place between pigments and their protein scaffold and how they affect the photophysical properties and the functionality of the complexes. We investigated variants of WSCP from Lepidium virginicum (Lv) and Brassica oleracea (Bo), reconstituted with Chlorophyll (Chl) b, to determine the mechanisms by which the different Chl binding sites control their Chl a/b specificities. A combined Raman and crystallographic investigation has been employed, aimed to characterize in detail the hydrogen-bond network involving the formyl group of Chl b. The study revealed a variable degree of conformational freedom of the hydrogen bond networks among the WSCP variants, and an unexpected mixed presence of hydrogen-bonded and not hydrogen-bonded Chls b in the case of the L91P mutant of Lv WSCP. These findings helped to refine the description of the mechanisms underlying the different Chl a/b specificities of WSCP versions, highlighting the importance of the structural rigidity of the Chl binding site in the vicinity of the Chl b formyl group in granting a strong selectivity to binding sites.
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Affiliation(s)
- Alessandro Agostini
- Department of Chemical Sciences, University of Padova, via Marzolo 1, 35131, Padova, Italy. .,Institute of Molecular Physiology, Johannes Gutenberg-University, Johannes-von-Müller-Weg 6, 55128, Mainz, Germany.
| | - Elena Meneghin
- Department of Chemical Sciences, University of Padova, via Marzolo 1, 35131, Padova, Italy
| | - Lucas Gewehr
- Institute of Molecular Physiology, Johannes Gutenberg-University, Johannes-von-Müller-Weg 6, 55128, Mainz, Germany
| | - Danilo Pedron
- Department of Chemical Sciences, University of Padova, via Marzolo 1, 35131, Padova, Italy
| | - Daniel M Palm
- Institute of Molecular Physiology, Johannes Gutenberg-University, Johannes-von-Müller-Weg 6, 55128, Mainz, Germany
| | - Donatella Carbonera
- Department of Chemical Sciences, University of Padova, via Marzolo 1, 35131, Padova, Italy
| | - Harald Paulsen
- Institute of Molecular Physiology, Johannes Gutenberg-University, Johannes-von-Müller-Weg 6, 55128, Mainz, Germany
| | - Elmar Jaenicke
- Institute of Molecular Physiology, Johannes Gutenberg-University, Jakob-Welder-Weg 26, 55128, Mainz, Germany
| | - Elisabetta Collini
- Department of Chemical Sciences, University of Padova, via Marzolo 1, 35131, Padova, Italy.
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