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Scholz F, Bamberg E, Bamann C, Wachtveitl J. Tuning the primary reaction of channelrhodopsin-2 by imidazole, pH, and site-specific mutations. Biophys J 2012; 102:2649-57. [PMID: 22713581 DOI: 10.1016/j.bpj.2012.04.034] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2011] [Revised: 03/12/2012] [Accepted: 04/19/2012] [Indexed: 01/11/2023] Open
Abstract
Femtosecond time-resolved absorption measurements were performed to investigate the influence of the pH, imidazole concentration, and point mutations on the isomerization process of Channelrhodopsin-2. Apart from the typical spectral characteristics of retinal isomerization, an additional absorption feature rises for the wild-type (wt) on a timescale from tens of ps to 1 ns within the spectral range of the photoproduct and is attributed to an equilibration between different K-intermediates. Remarkably, this absorption feature vanishes upon addition of imidazole or lowering the pH. In the latter case, the isomerization is dramatically slowed down, due to protonation of negatively charged amino acids within the retinal binding pocket, e.g., E123 and D253. Moreover, we investigated the influence of several point mutations within the retinal binding pocket E123T, E123D, C128T, and D156C. For E123T, the isomerization is retarded compared to wt and E123D, indicating that a negatively charged residue at this position functions as an effective catalyst in the isomerization process. In the case of the C128T mutant, all primary processes are slightly accelerated compared to the wt, whereas the isomerization dynamics for the D156C mutant is similar to wt after addition of imidazole.
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Affiliation(s)
- Frank Scholz
- Institute of Physical and Theoretical Chemistry, Johann Wolfgang Goethe-University, Frankfurt/Main, Germany
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2
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Mori T, Nakano K, Kato S. Conical intersections of free energy surfaces in solution: Effect of electron correlation on a protonated Schiff base in methanol solution. J Chem Phys 2010; 133:064107. [DOI: 10.1063/1.3472033] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
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3
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Jiao T, Zhou J, Liu M, Wang S, Zhou J, Zhang F. Supramolecular Assemblies and Self-Sorting of a Series of Cu(II)-Coordinated Schiff Bases Complexes at the Air/Water Interface. J DISPER SCI TECHNOL 2010. [DOI: 10.1080/01932690903224789] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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4
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Zgrablić G, Ricci M, Novello AM, Parmigiani F. Dependence of Photochemical Reactivity of the All-trans Retinal Protonated Schiff Base on the Solvent and the Excitation Wavelength. Photochem Photobiol 2010; 86:507-12. [DOI: 10.1111/j.1751-1097.2009.00697.x] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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5
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Verhoefen MK, Lenz MO, Amarie S, Klare JP, Tittor J, Oesterhelt D, Engelhard M, Wachtveitl J. Primary Reaction of Sensory Rhodopsin II Mutant D75N and the Influence of Azide. Biochemistry 2009; 48:9677-83. [DOI: 10.1021/bi901197c] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Mirka-Kristin Verhoefen
- Institute of Physical and Theoretical Chemistry, Institute of Biophysics, Johann Wolfgang Goethe-University Frankfurt, Max von Laue-Strasse 7, 60438 Frankfurt am Main, Germany
| | - Martin O. Lenz
- Institute of Physical and Theoretical Chemistry, Institute of Biophysics, Johann Wolfgang Goethe-University Frankfurt, Max von Laue-Strasse 7, 60438 Frankfurt am Main, Germany
| | - Sergiu Amarie
- Institute of Physical and Theoretical Chemistry, Institute of Biophysics, Johann Wolfgang Goethe-University Frankfurt, Max von Laue-Strasse 7, 60438 Frankfurt am Main, Germany
| | - Johann P. Klare
- Max-Planck-Institute of Molecular Physiology, Otto-Hahn-Strasse 11, 44139 Dortmund, Germany
| | - Jörg Tittor
- Max-Planck-Institute of Biochemistry, Am Klopferspitz 18, 82152 Martinsried, Germany
| | - Dieter Oesterhelt
- Max-Planck-Institute of Biochemistry, Am Klopferspitz 18, 82152 Martinsried, Germany
| | - Martin Engelhard
- Max-Planck-Institute of Molecular Physiology, Otto-Hahn-Strasse 11, 44139 Dortmund, Germany
| | - Josef Wachtveitl
- Institute of Physical and Theoretical Chemistry, Institute of Biophysics, Johann Wolfgang Goethe-University Frankfurt, Max von Laue-Strasse 7, 60438 Frankfurt am Main, Germany
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6
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Zgrablić G, Haacke S, Chergui M. Heterogeneity and Relaxation Dynamics of the Photoexcited Retinal Schiff Base Cation in Solution. J Phys Chem B 2009; 113:4384-93. [DOI: 10.1021/jp8077216] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Goran Zgrablić
- Ecole Polytechnique Fédérale de Lausanne, Laboratoire de Spectroscopie Ultrarapide, ISIC, Faculté des Sciences de Base, BSP, CH-1015 Lausanne-Dorigny, Switzerland, Sincrotrone Trieste Elettra, S.S. 14 km 163.5 in Area Science Park, 34012 Basovizza, Trieste, Italy, and Institut de Physique et Chimie des Matériaux de Strasbourg, UMR 7504 CNRS-ULP, 67034 Strasbourg Cédex, France
| | - Stefan Haacke
- Ecole Polytechnique Fédérale de Lausanne, Laboratoire de Spectroscopie Ultrarapide, ISIC, Faculté des Sciences de Base, BSP, CH-1015 Lausanne-Dorigny, Switzerland, Sincrotrone Trieste Elettra, S.S. 14 km 163.5 in Area Science Park, 34012 Basovizza, Trieste, Italy, and Institut de Physique et Chimie des Matériaux de Strasbourg, UMR 7504 CNRS-ULP, 67034 Strasbourg Cédex, France
| | - Majed Chergui
- Ecole Polytechnique Fédérale de Lausanne, Laboratoire de Spectroscopie Ultrarapide, ISIC, Faculté des Sciences de Base, BSP, CH-1015 Lausanne-Dorigny, Switzerland, Sincrotrone Trieste Elettra, S.S. 14 km 163.5 in Area Science Park, 34012 Basovizza, Trieste, Italy, and Institut de Physique et Chimie des Matériaux de Strasbourg, UMR 7504 CNRS-ULP, 67034 Strasbourg Cédex, France
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Kaczmarczyk B, Iwan A, Sek D. Temperature investigations of E/Z isomers in ketimines based of p-dibenzoylobenzene with aniline and 2,6-dimethylaniline by infrared spectroscopy. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2007; 68:369-76. [PMID: 17331796 DOI: 10.1016/j.saa.2006.12.004] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/07/2006] [Revised: 11/22/2006] [Accepted: 12/01/2006] [Indexed: 05/14/2023]
Abstract
The reaction of aniline with p-dibenzoylobenzene (K1) can lead to Z/Z, Z/E and E/E isomers however the only Z/Z and E/E were formed. At room temperature these isomers may be separated, thus the corresponding FTIR spectra could be recorded. The observed bands were assigned and temperature investigations were lead to monitor the structural changes during heating Z and E forms of K1 from 20 to 240 degrees C. FTIR spectroscopy showed that the bigger changes of the Z form was observed with an increase of temperature. Similar experience was lead with the ketimine synthesized from 2,6-dimethylaniline and p-dibenzoylobenzene (K2) investigated as a mixture of isomers.
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Affiliation(s)
- Bozena Kaczmarczyk
- Centre of Polymer Chemistry, Polish Academy of Science, 34 M. Curie-Sklodowska Street, 41-819 Zabrze, Poland.
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9
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Voïtchovsky K, Contera SA, Ryan JF. Electrostatic and steric interactions determine bacteriorhodopsin single-molecule biomechanics. Biophys J 2007; 93:2024-37. [PMID: 17513362 PMCID: PMC1959538 DOI: 10.1529/biophysj.106.101469] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
Bacteriorhodopsin (bR) is a haloarchaeal membrane protein that converts the energy of single photons into large structural changes to directionally pump protons across purple membrane. This is achieved by a complex combination of local dynamic interactions controlling bR biomechanics at the submolecular level, producing efficient amplification of the retinal photoisomerization. Using single molecule force spectroscopy at different salt concentrations, we show that tryptophan (Trp) residues use steric specific interactions to create a rigid scaffold in bR extracellular region and are responsible for the main unfolding barriers. This scaffold, which encloses the retinal, controls bR local mechanical properties and anchors the protein into the membrane. Furthermore, the stable Trp-based network allows ion binding to two specific sites on the extracellular loops (BC and FG), which are involved in proton release and lateral transport. In contrast, the cytoplasmic side of bR is mainly governed by relatively weak nonspecific electrostatic interactions that provide the flexibility necessary for large cytoplasmic structural rearrangements during the photocycle. The presence of an extracellular Trp-based network tightly enclosing the retinal seems common to most haloarchaeal rhodopsins, and could be relevant to their exceptional efficiency.
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Affiliation(s)
- Kislon Voïtchovsky
- Bionanotechnology Interdisciplinary Research Collaboration, Department of Physics, Clarendon Laboratory, University of Oxford, Oxford, United Kingdom
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Burghardt I, Hynes JT. Excited-State Charge Transfer at a Conical Intersection: Effects of an Environment. J Phys Chem A 2006; 110:11411-23. [PMID: 17020251 DOI: 10.1021/jp057569c] [Citation(s) in RCA: 78] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The influence of a polar and polarizable environment on charge transfer processes at a conical intersection (CI) can be described by a diabatic free energy model yielding coupled surfaces as a function of both molecular coordinates and a solvent coordinate. We extend and apply this model for the S1-S0 CI in protonated Schiff bases, representing a model for retinal isomerization (Faraday Discuss. 2004, 127, 395, 2004). A dielectric continuum description of the solvent is combined with a minimal, two-electron-two-orbital electronic structure model according to Bonacić-Koutecký, Koutecký, and Michl (Angew. Chem. 1987, 26, 170), which characterizes the charge translocation effects at the CI. The model predicts that the nonequilibrium solvent state resulting from the S0-->S1 Franck-Condon transition can entail the disappearance of the CI, such that solvent motion is necessary to reach the CI seam. The concerted evolution of the intramolecular coordinates and the solvent coordinate is illustrated by an excited-state minimum energy path.
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Affiliation(s)
- Irene Burghardt
- Département de Chimie, Ecole Normale Supérieure, 24 rue Lhomond, F-75231 Paris Cedex 05, France
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11
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Gunner MR, Mao J, Song Y, Kim J. Factors influencing the energetics of electron and proton transfers in proteins. What can be learned from calculations. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2006; 1757:942-68. [PMID: 16905113 PMCID: PMC2760439 DOI: 10.1016/j.bbabio.2006.06.005] [Citation(s) in RCA: 82] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/07/2006] [Revised: 06/07/2006] [Accepted: 06/13/2006] [Indexed: 11/15/2022]
Abstract
A protein structure should provide the information needed to understand its observed properties. Significant progress has been made in developing accurate calculations of acid/base and oxidation/reduction reactions in proteins. Current methods and their strengths and weaknesses are discussed. The distribution and calculated ionization states in a survey of proteins is described, showing that a significant minority of acidic and basic residues are buried in the protein and that most of these remain ionized. The electrochemistry of heme and quinones are considered. Proton transfers in bacteriorhodopsin and coupled electron and proton transfers in photosynthetic reaction centers, 5-coordinate heme binding proteins and cytochrome c oxidase are highlighted as systems where calculations have provided insight into the reaction mechanism.
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Affiliation(s)
- M R Gunner
- Physics Department City College of New York, New York, NY 10031, USA.
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12
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Abe M, Ohtsuki Y, Fujimura Y, Domcke W. Optimal control of ultrafastcis-transphotoisomerization of retinal in rhodopsin via a conical intersection. J Chem Phys 2005; 123:144508. [PMID: 16238408 DOI: 10.1063/1.2034488] [Citation(s) in RCA: 67] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
Optimal control simulation is applied to the cis-trans photoisomerization of retinal in rhodopsin within a two-dimensional, two-electronic-state model with a conical intersection [S. Hahn and G. Stock, J. Phys. Chem. B 104, 1146 (2000)]. For this case study, we investigate coherent control mechanisms, in which laser pulses work cooperatively with a conical intersection that acts as a "wave-packet cannon." Optimally designed pulses largely consist of shaping subpulses that prepare a wave packet, which is localized along a reaction coordinate and has little energy in the coupling mode, through multiple electronic transitions. This shaping process is shown to be essential for achieving a high target yield although the envelopes of the calculated pulses depend on the local topography of the potential-energy surfaces around the conical intersection and the choice of target. The control mechanisms are analyzed by considering the motion of reduced wave packets in a nuclear configuration space as well as by snapshots of probability current-density maps.
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Affiliation(s)
- Mayumi Abe
- Department of Chemistry, Graduate School of Science, Tohoku University, Sendai 980-8578, Japan
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13
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Zgrablić G, Voïtchovsky K, Kindermann M, Haacke S, Chergui M. Ultrafast excited state dynamics of the protonated Schiff base of all-trans retinal in solvents. Biophys J 2005; 88:2779-88. [PMID: 15792984 PMCID: PMC1305373 DOI: 10.1529/biophysj.104.046094] [Citation(s) in RCA: 81] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
We present a comparative study of the ultrafast photophysics of all-trans retinal in the protonated Schiff base form in solvents with different polarities and viscosities. Steady-state spectra of retinal in the protonated Schiff base form show large absorption-emission Stokes shifts (6500-8100 cm(-1)) for both polar and nonpolar solvents. Using a broadband fluorescence up-conversion experiment, the relaxation kinetics of fluorescence is investigated with 120 fs time resolution. The time-zero spectra already exhibit a Stokes-shift of approximately 6000 cm(-1), indicating depopulation of the Franck-Condon region in < or =100 fs. We attribute it to relaxation along skeletal stretching. A dramatic spectral narrowing is observed on a 150 fs timescale, which we assign to relaxation from the S(2) to the S(1) state. Along with the direct excitation of S(1), this relaxation populates different quasistationary states in S(1), as suggested from the existence of three distinct fluorescence decay times with different decay associated spectra. A 0.5-0.65 ps decay component is observed, which may reflect the direct repopulation of the ground state, in line with the small isomerization yield in solvents. Two longer decay components are observed and are attributed to torsional motion leading to photo-isomerization. The various decay channels show little or no dependence with respect to the viscosity or dielectric constant of the solvents. This suggests that in the protein, the bond selectivity of isomerization is mainly governed by steric effects.
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Affiliation(s)
- Goran Zgrablić
- Laboratoire de Spectroscopie Ultrarapide, Ecole Polytechnique Fédérale de Lausanne, Institute of Chemical Sciences and Engineering, FSB-BSP, CH-1015 Lausanne-Dorigny, Switzerland
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14
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Jiao T, Liu M. Supramolecular Assemblies and Molecular Recognition of Amphiphilic Schiff Bases with Barbituric Acid in Organized Molecular Films. J Phys Chem B 2005; 109:2532-9. [PMID: 16851253 DOI: 10.1021/jp045258g] [Citation(s) in RCA: 70] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
A bolaform Schiff base, N,N'-bis(salicylidene)-1,10-decanediamine (BSC10), has been synthesized and its interfacial hydrogen bond formation or molecular recognition with barbituric acid was investigated in comparison with that of a single chain Schiff base, 2-hydroxybenzaldehyde-octadecylamine (HBOA). It has been found that while HBOA formed a monolayer at the air/water interface, the bolaform Schiff base formed a multilayer film with ordered layer structure on water surface. When the Schiff bases were spread on the subphase containing barbituric acid, both of the Schiff bases could form hydrogen bonds with barbituric acid in situ in the spreading films. As a result, an increase of the molecular areas in the isotherms was observed. The in situ H-bonded films could be transferred onto solid substrates, and the transferred multilayer films were characterized by various methods such as UV-vis and FT-IR spectrosopies. Spectral changes were observed for the films deposited from the barbituric acid subphase, which supported the hydrogen bond formation between the Schiff bases and barbituric acid. By measuring the MS-TOF of the deposited films dissolved in CHCl3 solution, it was concluded that a 2:1 complex of HBOA with barbituric acid and a 1:2 complex of BSC10 with barbituric acid were formed. On the other hand, when the multilayer films of both Schiff bases were immersed in an aqueous solution of barbituric acid, a similar molecular recognition through the hydrogen bond occurred. A clear conformational change of the alkyl spacer in the bolaform Schiff base was observed during the complex formation with the barbituric acid.
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Affiliation(s)
- Tifeng Jiao
- CAS Key Laboratory of Colloid and Interface Science, Center for Molecular Science, Institute of Chemistry, CAS, Beijing 100080, People's Republic of China
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15
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Cembran A, Bernardi F, Olivucci M, Garavelli M. Counterion Controlled Photoisomerization of Retinal Chromophore Models: a Computational Investigation. J Am Chem Soc 2004; 126:16018-37. [PMID: 15584736 DOI: 10.1021/ja048782+] [Citation(s) in RCA: 80] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
CASPT2//CASSCF photoisomerization path computations have been used to unveil the effects of an acetate counterion on the photochemistry of two retinal protonated Schiff base (PSB) models: the 2-cis-penta-2,4-dieniminium and the all-trans-epta-2,4,6-trieniminium cations. Different positions/orientations of the counterion have been investigated and related to (i) the spectral tuning and relative stability of the S0, S1, and S2 singlet states; (ii) the selection of the photochemically relevant excited state; (iii) the control of the radiationless decay and photoisomerization rates; and, finally, (iv) the control of the photoisomerization stereospecificity. A rationale for the results is given on the basis of a simple (electrostatic) qualitative model. We show that the model readily explains the computational results providing a qualitative explanation for different aspects of the experimentally observed "environment" dependent PSB photochemistry. Electrostatic effects likely involved in controlling retinal photoisomerization stereoselectivity in the protein are also discussed under the light of these results, and clues for a stereocontrolled electrostatically driven photochemical process are presented. These computations provide a rational basis for the formulation of a mechanistic model for photoisomerization electrostatic catalysis.
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Affiliation(s)
- Alessandro Cembran
- Dipartimento di Chimica G. Ciamician, Università di Bologna, via Selmi 2, Bologna, I-40126 Italy
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Sampedro D, Migani A, Pepi A, Busi E, Basosi R, Latterini L, Elisei F, Fusi S, Ponticelli F, Zanirato V, Olivucci M. Design and photochemical characterization of a biomimetic light-driven Z/E switcher. J Am Chem Soc 2004; 126:9349-59. [PMID: 15281826 DOI: 10.1021/ja038859e] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Protonated Schiff bases (PSBs) of polyenals constitute a class of light-driven switchers selected by biological evolution that provide model compounds for the development of artificial light-driven molecular devices or motors. In the present paper, our primary target is to show, through combined computational and experimental studies, that it is possible to approach the design of artificial PSBs suitable for such applications. Below, we use the methods of computational photochemistry to design and characterize the prototype biomimetic molecular switchers 4-cyclopenten-2'-enylidene-3,4-dihydro-2H-pyrrolinium and its 5,5'-dimethyl derivative both containing the penta-2,4-dieniminium chromophore. To find support for the predicted behavior, we also report the photochemical reaction path of the synthetically accessible compound 4-benzylidene-3,4-dihydro-2H-pyrrolinium. We show that the preparation and photochemical characterization of this compound (together with three different N-methyl derivatives) provide both support for the predicted photoisomerization mechanism and information on its sensitivity to the molecular environment.
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Affiliation(s)
- Diego Sampedro
- Dipartimento di Chimica, Università di Siena, Via Aldo Moro 2, I-53100 Siena, Italy
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Song Y, Mao J, Gunner MR. Calculation of proton transfers in Bacteriorhodopsin bR and M intermediates. Biochemistry 2003; 42:9875-88. [PMID: 12924936 DOI: 10.1021/bi034482d] [Citation(s) in RCA: 54] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Residue ionization states were calculated in nine crystal structures of bacteriorhodopsin trapped in bR, early M, and late M states by multiconformation continuum electrostatics. This combines continuum electrostatics and molecular mechanics, deriving equilibrium distributions of ionization states and polar residue and water positions. The three central cluster groups [retinal Schiff base (SB), Asp 85 and Asp 212] are ionized in bR structures while a proton has transferred from SB(+) to Asp 85(-) in late M structures matching experimental results. The proton shift in M is due to weaker SB(+)-ionized acid and more favorable SB(0)-ionized acid interactions following retinal isomerization. The proton release cluster (Glu 194 and Glu 204) binds one proton in bR, which is lost to water by pH 8 in late M. In bR the half-ionized state is stabilized by charge-dipole interactions while full ionization is disallowed by charge-charge repulsion between the closely spaced acids. In M the acids move apart, permitting full ionization. Arg 82 movement connects the proton shifts in the central and proton release clusters. Changes in total charge of the two clusters are coupled by direct long-range interactions. Separate calculations consider continuum or explicit water in internal cavities. The explicit waters and nearby polar residues can reorient to stabilize different charge distributions. Proton release to the low-pH, extracellular side of the protein occurs in these calculations where residue ionization remains at equilibrium with the medium. Thus, the key changes distinguishing the intermediates are indeed trapped in the structures.
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Affiliation(s)
- Yifan Song
- Physics Department J-419, City College of New York, 138th Street and Convent Avenue, New York, New York 10031, USA
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18
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Blomgren F, Larsson S. Initial step of the photoprocess leading to vision only requires minimal atom displacements in the retinal molecule. Chem Phys Lett 2003. [DOI: 10.1016/s0009-2614(03)01062-5] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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Ohtsuki Y, Ohara K, Abe M, Nakagami K, Fujimura Y. New quantum control pathway for a coupled-potential system. Chem Phys Lett 2003. [DOI: 10.1016/s0009-2614(02)02030-4] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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20
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Scherer P, Fischer SF. Vibronic couplings and radiationless transitions between the lowest 1Bu and the first excited 2Ag state of linear polyenes. J Photochem Photobiol A Chem 2001. [DOI: 10.1016/s1010-6030(01)00571-8] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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21
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Warshel A, Chu ZT. Nature of the Surface Crossing Process in Bacteriorhodopsin: Computer Simulations of the Quantum Dynamics of the Primary Photochemical Event. J Phys Chem B 2001. [DOI: 10.1021/jp010704a] [Citation(s) in RCA: 140] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- A. Warshel
- Department of Chemistry, University of Southern California, University Park Campus, Los Angeles, California 90089-1062
| | - Z. T. Chu
- Department of Chemistry, University of Southern California, University Park Campus, Los Angeles, California 90089-1062
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