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Palombo R, Barneschi L, Pedraza-González L, Yang X, Olivucci M. Picosecond quantum-classical dynamics reveals that the coexistence of light-induced microbial and animal chromophore rotary motion modulates the isomerization quantum yield of heliorhodopsin. Phys Chem Chem Phys 2024; 26:10343-10356. [PMID: 38501246 DOI: 10.1039/d4cp00193a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/20/2024]
Abstract
Rhodopsins are light-responsive proteins forming two vast and evolutionary distinct superfamilies whose functions are invariably triggered by the photoisomerization of a single retinal chromophore. In 2018 a third widespread superfamily of rhodopsins called heliorhodopsins was discovered using functional metagenomics. Heliorhodopsins, with their markedly different structural features with respect to the animal and microbial superfamilies, offer an opportunity to study how evolution has manipulated the chromophore photoisomerization to achieve adaptation. One question is related to the mechanism of such a reaction and how it differs from that of animal and microbial rhodopsins. To address this question, we use hundreds of quantum-classical trajectories to simulate the spectroscopically documented picosecond light-induced dynamics of a heliorhodopsin from the archaea thermoplasmatales archaeon (TaHeR). We show that, consistently with the observations, the trajectories reveal two excited state decay channels. However, inconsistently with previous hypotheses, only one channel is associated with the -C13C14- rotation of microbial rhodopsins while the second channel is characterized by the -C11C12- rotation typical of animal rhodopsins. The fact that such -C11C12- rotation is aborted upon decay and ground state relaxation, explains why illumination of TaHeR only produces the 13-cis isomer with a low quantum efficiency. We argue that the documented lack of regioselectivity in double-bond excited state twisting motion is the result of an "adaptation" that could be completely lost via specific residue substitutions modulating the steric hindrance experienced along the isomerization motion.
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Affiliation(s)
- Riccardo Palombo
- Dipartimento di Biotecnologie, Chimica e Farmacia, Università di Siena, via A. Moro 2, I-53100 Siena, Siena, Italy.
- Department of Chemistry, Bowling Green State University, Bowling Green, Ohio 43403, USA.
| | - Leonardo Barneschi
- Dipartimento di Biotecnologie, Chimica e Farmacia, Università di Siena, via A. Moro 2, I-53100 Siena, Siena, Italy.
| | - Laura Pedraza-González
- Dipartimento di Chimica e Chimica Industriale, Università di Pisa, Via Giuseppe Moruzzi, 13, I-56124 Pisa, Italy
| | - Xuchun Yang
- Department of Chemistry, Bowling Green State University, Bowling Green, Ohio 43403, USA.
| | - Massimo Olivucci
- Dipartimento di Biotecnologie, Chimica e Farmacia, Università di Siena, via A. Moro 2, I-53100 Siena, Siena, Italy.
- Department of Chemistry, Bowling Green State University, Bowling Green, Ohio 43403, USA.
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2
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Kandori H. Structure/Function Study of Photoreceptive Proteins by FTIR Spectroscopy. BULLETIN OF THE CHEMICAL SOCIETY OF JAPAN 2020. [DOI: 10.1246/bcsj.20200109] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Affiliation(s)
- Hideki Kandori
- Department of Life Science and Applied Chemistry & OptoBioTechnology Research Center, Nagoya Institute of Technology, Showa-ku, Nagoya, Aichi 466-8555, Japan
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3
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Shigaev AS, Feldman TB, Nadtochenko VA, Ostrovsky MA, Lakhno VD. Quantum-classical model of the rhodopsin retinal chromophore cis–trans photoisomerization with modified inter-subsystem coupling. COMPUT THEOR CHEM 2020. [DOI: 10.1016/j.comptc.2020.112831] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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4
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Kataoka C, Inoue K, Katayama K, Béjà O, Kandori H. Unique Photochemistry Observed in a New Microbial Rhodopsin. J Phys Chem Lett 2019; 10:5117-5121. [PMID: 31433641 DOI: 10.1021/acs.jpclett.9b01957] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Light energy is first captured in animal and microbial rhodopsins by ultrafast photoisomerization, whose relaxation accompanies protein structural changes for each function. Here, we report a microbial rhodopsin, marine bacterial TAT rhodopsin, that displays no formation of photointermediates at >10-5 s. Low-temperature ultraviolet-visible and Fourier transform infrared spectroscopy revealed that TAT rhodopsin features all-trans to 13-cis photoisomerization like other microbial rhodopsins, but a planar 13-cis chromophore in the primary K intermediate seems to favor thermal back isomerization to the original state without photocycle completion. The molecular mechanism of the early photoreaction in TAT rhodopsin will be discussed.
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Affiliation(s)
- Chihiro Kataoka
- Department of Life Science and Applied Chemistry, Nagoya Institute of Technology, Showa-ku, Nagoya 466-8555, Japan
| | - Keiichi Inoue
- Department of Life Science and Applied Chemistry, Nagoya Institute of Technology, Showa-ku, Nagoya 466-8555, Japan
- OptoBioTechnology Research Center, Nagoya Institute of Technology, Showa-ku, Nagoya 466-8555, Japan
- The Institute for Solid State Physics, The University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa, Chiba 277-8581, Japan
- PRESTO, Japan Science and Technology Agency, 4-1-8 Honcho, Kawaguchi, Saitama 332-0012, Japan
| | - Kota Katayama
- Department of Life Science and Applied Chemistry, Nagoya Institute of Technology, Showa-ku, Nagoya 466-8555, Japan
- OptoBioTechnology Research Center, Nagoya Institute of Technology, Showa-ku, Nagoya 466-8555, Japan
| | - Oded Béjà
- Faculty of Biology, Technion-Israel Institute of Technology, Haifa 3200003, Israel
| | - Hideki Kandori
- Department of Life Science and Applied Chemistry, Nagoya Institute of Technology, Showa-ku, Nagoya 466-8555, Japan
- OptoBioTechnology Research Center, Nagoya Institute of Technology, Showa-ku, Nagoya 466-8555, Japan
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5
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Grabarek D, Andruniów T. Initial excited-state relaxation of locked retinal protonated schiff base chromophore. An insight from coupled cluster and multireference perturbation theory calculations. J Comput Chem 2018; 39:1720-1727. [PMID: 29727036 DOI: 10.1002/jcc.25346] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2018] [Revised: 04/06/2018] [Accepted: 04/12/2018] [Indexed: 11/07/2022]
Abstract
The initial S1 excited-state relaxation of retinal protonated Schiff base (RPSB) analog with central C11C12 double bond locked by eight-membered ring (locked-11.8) was investigated by means of multireference perturbation theory methods (XMCQDPT2, XMS-CASPT2, MS-CASPT2) as well as single-reference coupled-cluster CC2 method. The analysis of XMCQDPT2-based geometries reveals rather weak coupling between in-plane and out-of-plane structural evolution and minor energetical relaxation of three locked-11.8 conformers. Therefore, a strong coupling between bonds length inversion and backbone out-of-plane deformation resulting in a very steep S1 energy profile predicted by CASSCF/CASPT2 calculations is in clear contradiction with the reference XMCQDPT2 results. Even though CC2 method predicts good quality ground-state structures, the excited-state structures display more advanced torsional deformation leading to ca. 0.2 eV exaggerated energy relaxation and significantly red shifted (0.4-0.7 eV) emission maxima. According to our findings, the initial photoisomerization process in locked-11.8, and possibly in other RPSB analogs, studied fully (both geometries and energies) by multireference perturbation theory may be somewhat slower than predicted by CASSCF/CASPT2 or CC2 methods. © 2018 Wiley Periodicals, Inc.
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Affiliation(s)
- Dawid Grabarek
- Advanced Materials Engineering and Modelling Group, Wroclaw University of Science and Technology, Wyb. Wyspianskiego 27, Wroclaw, 50-370, Poland
| | - Tadeusz Andruniów
- Advanced Materials Engineering and Modelling Group, Wroclaw University of Science and Technology, Wyb. Wyspianskiego 27, Wroclaw, 50-370, Poland
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6
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Gozem S, Luk HL, Schapiro I, Olivucci M. Theory and Simulation of the Ultrafast Double-Bond Isomerization of Biological Chromophores. Chem Rev 2017; 117:13502-13565. [DOI: 10.1021/acs.chemrev.7b00177] [Citation(s) in RCA: 175] [Impact Index Per Article: 25.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Affiliation(s)
- Samer Gozem
- Department
of Chemistry, Georgia State University, Atlanta, Georgia 30302, United States
| | - Hoi Ling Luk
- Chemistry
Department, Bowling Green State University, Overman Hall, Bowling Green, Ohio 43403, United States
| | - Igor Schapiro
- Fritz
Haber Center for Molecular Dynamics, Institute of Chemistry, The Hebrew University of Jerusalem, Jerusalem 91904, Israel
| | - Massimo Olivucci
- Chemistry
Department, Bowling Green State University, Overman Hall, Bowling Green, Ohio 43403, United States
- Dipartimento
di Biotecnologie, Chimica e Farmacia, Università di Siena, via A. Moro
2, 53100 Siena, Italy
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7
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Schapiro I. The Origin of Bond Selectivity and Excited-State Reactivity in Retinal Analogues. J Phys Chem A 2016; 120:3353-65. [DOI: 10.1021/acs.jpca.6b00701] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Igor Schapiro
- Fritz Haber
Center for Molecular
Dynamics, Institute of Chemistry, The Hebrew University of Jerusalem, Jerusalem 91904, Israel
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8
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Origin of the low thermal isomerization rate of rhodopsin chromophore. Sci Rep 2015; 5:11081. [PMID: 26061742 PMCID: PMC4462023 DOI: 10.1038/srep11081] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2015] [Accepted: 05/14/2015] [Indexed: 02/07/2023] Open
Abstract
Low dark noise is a prerequisite for rod cells, which mediate our dim-light vision. The low dark noise is achieved by the extremely stable character of the rod visual pigment, rhodopsin, which evolved from less stable cone visual pigments. We have developed a biochemical method to quickly evaluate the thermal activation rate of visual pigments. Using an isomerization locked chromophore, we confirmed that thermal isomerization of the chromophore is the sole cause of thermal activation. Interestingly, we revealed an unexpected correlation between the thermal stability of the dark state and that of the active intermediate MetaII. Furthermore, we assessed key residues in rhodopsin and cone visual pigments by mutation analysis and identified two critical residues (E122 and I189) in the retinal binding pocket which account for the extremely low thermal activation rate of rhodopsin.
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Shelaev IV, Mozgovaya MN, Smitienko OA, Gostev FE, Fel’dman TB, Nadtochenko VA, Sarkisov OM, Ostrovskii MA. Femtosecond dynamics of primary processes in visual pigment rhodopsin. RUSSIAN JOURNAL OF PHYSICAL CHEMISTRY B 2014. [DOI: 10.1134/s1990793114040101] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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10
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Ernst OP, Lodowski DT, Elstner M, Hegemann P, Brown L, Kandori H. Microbial and animal rhodopsins: structures, functions, and molecular mechanisms. Chem Rev 2014; 114:126-63. [PMID: 24364740 PMCID: PMC3979449 DOI: 10.1021/cr4003769] [Citation(s) in RCA: 759] [Impact Index Per Article: 75.9] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2013] [Indexed: 12/31/2022]
Affiliation(s)
- Oliver P. Ernst
- Departments
of Biochemistry and Molecular Genetics, University of Toronto, 1 King’s College Circle, Medical Sciences Building, Toronto, Ontario M5S 1A8, Canada
| | - David T. Lodowski
- Center
for Proteomics and Bioinformatics, Case
Western Reserve University School of Medicine, 10900 Euclid Avenue, Cleveland, Ohio 44106, United States
| | - Marcus Elstner
- Institute
for Physical Chemistry, Karlsruhe Institute
of Technology, Kaiserstrasse
12, 76131 Karlsruhe, Germany
| | - Peter Hegemann
- Institute
of Biology, Experimental Biophysics, Humboldt-Universität
zu Berlin, Invalidenstrasse
42, 10115 Berlin, Germany
| | - Leonid
S. Brown
- Department
of Physics and Biophysics Interdepartmental Group, University of Guelph, 50 Stone Road East, Guelph, Ontario N1G 2W1, Canada
| | - Hideki Kandori
- Department
of Frontier Materials, Nagoya Institute
of Technology, Showa-ku, Nagoya 466-8555, Japan
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11
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Nakanishi K, Crouch R. Application of Artificial Pigments to Structure Determination and Study of Photoinduced Transformations of Retinal Proteins. Isr J Chem 2013. [DOI: 10.1002/ijch.199500030] [Citation(s) in RCA: 102] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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12
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Walczak E, Szefczyk B, Andruniów T. Geometries and Vertical Excitation Energies in Retinal Analogues Resolved at the CASPT2 Level of Theory: Critical Assessment of the Performance of CASSCF, CC2, and DFT Methods. J Chem Theory Comput 2013; 9:4915-27. [DOI: 10.1021/ct400423u] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Elżbieta Walczak
- Wroclaw University of Technology, Institute of Physical & Theoretical Chemistry, Wyb. Wyspianskiego 27, 50-370 Wroclaw, Poland
| | - Borys Szefczyk
- Wroclaw University of Technology, Institute of Physical & Theoretical Chemistry, Wyb. Wyspianskiego 27, 50-370 Wroclaw, Poland
| | - Tadeusz Andruniów
- Wroclaw University of Technology, Institute of Physical & Theoretical Chemistry, Wyb. Wyspianskiego 27, 50-370 Wroclaw, Poland
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13
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Kim JE, McCamant DW, Zhu L, Mathies RA. Resonance Raman Structural Evidence that the Cis-to-Trans Isomerization in Rhodopsin Occurs in Femtoseconds. J Phys Chem B 2012; 105:1240-9. [PMID: 16755302 PMCID: PMC1473983 DOI: 10.1021/jp001236s] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Picosecond time-resolved resonance Raman spectroscopy is used to probe the structural changes of rhodopsin's retinal chromophore as the cis-to-trans isomerization reaction occurs that initiates vision. Room-temperature resonance Raman spectra of rhodopsin's photoproduct with time delays from -0.7 to 20.8 ps are measured using 2.2 ps, 480 nm pump and 1.5 ps, 600 nm probe pulses. Hydrogen-out-of-plane (HOOP) modes at 852, 871, and 919 cm(-1), fingerprint peaks at 1272, 1236, 1211, and 1166 cm(-1), and a broad red-shifted ethylenic band at 1530 cm(-1) are present at the earliest positive pump-probe time delay of 0.8 ps, indicating that the chromophore is already in a strained, all-trans configuration. Kinetic analyses of both the HOOP and ethylenic regions of the photoproduct spectra reveal that these features grow in with fast ( approximately 200 fs) and slow ( approximately 2-3 ps) components. These data provide the first structural evidence that photorhodopsin has a thermally unrelaxed, torsionally strained all-trans chromophore within approximately 1 ps, and possibly within 200 fs, of photon absorption. Following this ultrafast product formation, the all-trans chromophore cools and conformationally relaxes within a few picoseconds to form bathorhodopsin. This cooling process is revealed as an ethylenic frequency blue-shift of 6 cm(-1) (tau approximately 3.5 ps) as well as an ethylenic width narrowing (tau approximately 2 ps). The ultrafast production of photorhodopsin is likely accompanied by an impulsively driven, localized protein response. More delocalized protein modes are unable to relax on this ultrafast time scale enabling the chromophore-protein complex to store the large amounts of photon energy (30-35 kcal/mol) that are subsequently used to drive activating protein conformational changes.
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Affiliation(s)
- J E Kim
- Department of Chemistry, University of California, Berkeley, California 94720
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14
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15
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Smitienko OA, Mozgovaya MN, Shelaev IV, Gostev FE, Feldman TB, Nadtochenko VA, Sarkisov OM, Ostrovsky MA. Femtosecond formation dynamics of primary photoproducts of visual pigment rhodopsin. BIOCHEMISTRY (MOSCOW) 2010; 75:25-35. [DOI: 10.1134/s0006297910010049] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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16
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Send R, Sundholm D. The Role of the β-Ionone Ring in the Photochemical Reaction of Rhodopsin. J Phys Chem A 2006; 111:27-33. [PMID: 17201384 DOI: 10.1021/jp065510f] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Time-dependent density functional theory (TDDFT) calculations on the photoabsorption process of the 11-cis retinal protonated Schiff base (PSB) chromophore show that the Franck-Condon relaxation of the first excited state of the chromophore involves a torsional twist motion of the beta-ionone ring relative to the conjugated retinyl chain. For the ground state, the beta-ionone ring and the retinyl chain of the free retinal PSB chromophore form a -40 degrees dihedral angle as compared to -94 degrees for the first excited state. The double bonds of the retinal are shorter for the fully optimized structure of the excited state than for the ground state suggesting a higher cis-trans isomerization barrier for the excited state than for the ground state. According to the present TDDFT calculations, the excitation of the retinal PSB chromophore does not primarily lead to a reaction along the cis-trans torsional coordinate at the C11-C12 bond. The activation of the isomerization center seems to occur at a later stage of the photo reaction. The results obtained at the TDDFT level are supported by second-order Møller-Plesset (MP2) and approximate singles and doubles-coupled cluster (CC2) calculations on retinal chromophore models; the MP2 and CC2 calculations yield for them qualitatively the same ground state and excited-state structures as obtained in the density functional theory and TDDFT calculations.
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Affiliation(s)
- Robert Send
- Institut für Physikalische Chemie, Universität Karlsruhe, Kaiserstrasse 12, D-76128 Karlsruhe, Germany
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17
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De Vico L, Garavelli M, Bernardi F, Olivucci M. Photoisomerization Mechanism of 11-cis-Locked Artificial Retinal Chromophores: Acceleration and Primary Photoproduct Assignment. J Am Chem Soc 2005; 127:2433-42. [PMID: 15724998 DOI: 10.1021/ja045747u] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
CASPT2//CASSCF/6-31G photochemical reaction path computations for two 4-cis-nona-2,4,6,8-tetraeniminium cation derivatives, with the 4-cis double bond embedded in a seven- and eight-member ring, are carried out to model the reactivity of the corresponding ring-locked retinal chromophores. The comparison of the excited state branches of the two reaction paths with that of the native chromophore, is used to unveil the factors responsible for the remarkably short (60 fs) excited state (S(1)) lifetime observed when an artificial rhodopsin containing an eight member ring-locked retinal is photoexcited. Indeed, it is shown that the strain imposed by the eight-member ring on the chromophore backbone leads to a dramatic change in the shape of the S(1) energy surface. Our models are also used to investigate the nature of the primary photoproducts observed in different artificial rhodopsins. It is seen that only the eight member ring-locked retinal model can access a shallow energy minimum on the ground state. This result implies that the primary, photorhodopsin-like, transient observed in artificial rhodopsins could correspond to a shallow excited state minimum. Similarly, the second, bathorhodopsin-like, transient species could be assigned to a ground state structure displaying a nearly all-trans conformation.
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Affiliation(s)
- Luca De Vico
- Dipartimento di Chimica, Università di Siena, via De Gasperi 2 Siena, I-53100 Italy
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Liu RSH, Colmenares LU. The molecular basis for the high photosensitivity of rhodopsin. Proc Natl Acad Sci U S A 2003; 100:14639-44. [PMID: 14657350 PMCID: PMC299751 DOI: 10.1073/pnas.2536769100] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2003] [Indexed: 11/18/2022] Open
Abstract
Based on structural information derived from the F NMR data of labeled rhodopsins, rhodopsin crystal structure, and excited-state properties of model polyenes, we propose a molecular mechanism that accounts specifically for the causes of the well-known enhanced photoreactivity of rhodopsin (increased rates and quantum yield of isomerization). It involves the key features of close proximity of C-187 to H-12 and chromophore bond lengthening upon light absorption. The resultant "sudden punch" to H-12 triggers dual processes of decay of the Franck-Condon-excited rhodopsin, a productive directed photoisomerization and a nonproductive decay returning to the ground state as two separate molecular pathways [based on real-time fluorescence results of Chosrowjan, H., Mataga, N., Shibata, Y., Tachibanaki, S., Kandori, H., Shichida, Y., Okada, T. & Kouyama, T. (1998) J. Am. Chem. Soc. 120, 9706-9707]. The two processes are controlled by the local protein structure: an empty space provided by the intradiscal loop connecting transmembrane helices 4 and 5 and a protein wall composed of amino acid units in transmembrane 3. Suggestions, involving retinal analogs and rhodopsin mutants, to improve the unusually high photosensitivity of rhodopsin are proposed.
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Affiliation(s)
- Robert S H Liu
- Department of Chemistry, University of Hawaii, Honolulu, HI 96822, USA.
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20
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Fan G, Siebert F, Sheves M, Vogel R. Rhodopsin with 11-cis-locked chromophore is capable of forming an active state photoproduct. J Biol Chem 2002; 277:40229-34. [PMID: 12177057 DOI: 10.1074/jbc.m205033200] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The visual pigment rhodopsin is characterized by an 11-cis retinal chromophore bound to Lys-296 via a protonated Schiff base. Following light absorption the C(11)=C(12) double bond isomerizes to trans configuration and triggers protein conformational alterations. These alterations lead to the formation of an active intermediate (Meta II), which binds and activates the visual G protein, transducin. We have examined by UV-visible and Fourier transform IR spectroscopy the photochemistry of a rhodopsin analogue with an 11-cis-locked chromophore, where cis to trans isomerization around the C(11)=C(12) double bond is prevented by a 6-member ring structure (Rh(6.10)). Despite this lock, the pigment was found capable of forming an active photoproduct with a characteristic protein conformation similar to that of native Meta II. This intermediate is further characterized by a protonated Schiff base and protonated Glu-113, as well as by its ability to bind a transducin-derived peptide previously shown to interact efficiently with native Meta II. The yield of this active photointermediate is pH-dependent and decreases with increasing pH. This study shows that with the C(11)=C(12) double bond being locked, isomerization around the C(9)=C(10) or the C(13)=C(14) double bonds may well lead to an activation of the receptor. Additionally, prolonged illumination at pH 7.5 produces a new photoproduct absorbing at 385 nm, which, however, does not exhibit the characteristic active protein conformation.
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Affiliation(s)
- Guibao Fan
- Department of Organic Chemistry, Weizmann Institute of Science, Rehovot 76100, Israel
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21
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Lee HM, Kim J, Kim CJ, Kim KS. Ab initio study of the isomerization of retinal chromophore and its derivatives. J Chem Phys 2002. [DOI: 10.1063/1.1459705] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
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22
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Nagata T, Oura T, Terakita A, Kandori H, Shichida Y. Isomer-Specific Interaction of the Retinal Chromophore with Threonine-118 in Rhodopsin. J Phys Chem A 2002. [DOI: 10.1021/jp0124488] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Tomoko Nagata
- Department of Biophysics, Graduate School of Science, Kyoto University, Sakyo-ku, Kyoto 606-8502, Japan
| | - Tomonori Oura
- Department of Biophysics, Graduate School of Science, Kyoto University, Sakyo-ku, Kyoto 606-8502, Japan
| | - Akihisa Terakita
- Department of Biophysics, Graduate School of Science, Kyoto University, Sakyo-ku, Kyoto 606-8502, Japan
| | - Hideki Kandori
- Department of Biophysics, Graduate School of Science, Kyoto University, Sakyo-ku, Kyoto 606-8502, Japan
| | - Yoshinori Shichida
- Department of Biophysics, Graduate School of Science, Kyoto University, Sakyo-ku, Kyoto 606-8502, Japan
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23
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Hou B, Friedman N, Ruhman S, Sheves M, Ottolenghi M. Ultrafast Spectroscopy of the Protonated Schiff Bases of Free and C13C14 Locked Retinals. J Phys Chem B 2001. [DOI: 10.1021/jp0034980] [Citation(s) in RCA: 56] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- B. Hou
- Department of Physical Chemistry, The Hebrew University, Jerusalem 91904, Israel and The Weizmann Institute of Science, Rehovot 76100, Israel
| | - N. Friedman
- Department of Physical Chemistry, The Hebrew University, Jerusalem 91904, Israel and The Weizmann Institute of Science, Rehovot 76100, Israel
| | - S. Ruhman
- Department of Physical Chemistry, The Hebrew University, Jerusalem 91904, Israel and The Weizmann Institute of Science, Rehovot 76100, Israel
| | - M. Sheves
- Department of Physical Chemistry, The Hebrew University, Jerusalem 91904, Israel and The Weizmann Institute of Science, Rehovot 76100, Israel
| | - M. Ottolenghi
- Department of Physical Chemistry, The Hebrew University, Jerusalem 91904, Israel and The Weizmann Institute of Science, Rehovot 76100, Israel
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Verdegem PJ, Monnee MC, Lugtenburg J. Simple and efficient preparation of [10,20-13C2]- and [10-CH3,13-13C2]-10-methylretinal: introduction of substituents at the 2-position of 2,3-unsaturated nitriles. J Org Chem 2001; 66:1269-82. [PMID: 11312957 DOI: 10.1021/jo0009595] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
In this paper, we present the synthesis of [10,20-13C2]-10-methylretinal and [10-CH3,13-13C2]-10-methylretinal, two doubly 13C-labeled chemically modified retinals that have been recently used to study the structural and functional details behind the photocascade of bovine rhodopsin (Verdegem et al. Biochemistry 1999, 38, 11316; de Lange et al. Biochemistry 1998, 37, 1411). To obtain both doubly 13C-labeled compounds, we developed a novel synthetic method to directly and regiospecifically introduce a methyl substituent on the 2-position of 3-methyl-5-(2',6',6'-trimethyl-1'-cyclohexen-1'-yl)-2,4-pentadienenitrile. Encouraged by these results, we investigated the scope of this novel reaction by developing a general method for the introduction of a variety of substituents to the 2-position of 3-methyl-2,3-unsaturated nitriles, paving the way for simple and efficient synthesis of a wide variety of 10-, 14-, and 10,14-substituted chemically modified retinals, and other biologically important compounds.
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Affiliation(s)
- P J Verdegem
- Leiden Institute of Chemistry, Leiden University, Gorlaeus Laboratoria, P.O. Box 9502, 2300 RA Leiden, The Netherlands
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Kandori H, Furutani Y, Nishimura S, Shichida Y, Chosrowjan H, Shibata Y, Mataga N. Excited-state dynamics of rhodopsin probed by femtosecond fluorescence spectroscopy. Chem Phys Lett 2001. [DOI: 10.1016/s0009-2614(00)01457-3] [Citation(s) in RCA: 85] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Chosrowjan H, Mataga N, Shibata Y, Tachibanaki S, Kandori H, Shichida Y, Okada T, Kouyama T. Rhodopsin Emission in Real Time: A New Aspect of the Primary Event in Vision. J Am Chem Soc 1998. [DOI: 10.1021/ja981659w] [Citation(s) in RCA: 60] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Haik Chosrowjan
- Institute for Laser Technology, Utsubo-Hommachi 1-8-4 Nishi-ku, Osaka 550, Japan Department of Biophysics, Graduate School of Science Kyoto University, Sakyo-ku, Kyoto 601-01, Japan Department of Physics, Graduate School of Science Nagoya University, Furo-cho Chikusa-ku, Nagoya 464-01, Japan
| | - Noboru Mataga
- Institute for Laser Technology, Utsubo-Hommachi 1-8-4 Nishi-ku, Osaka 550, Japan Department of Biophysics, Graduate School of Science Kyoto University, Sakyo-ku, Kyoto 601-01, Japan Department of Physics, Graduate School of Science Nagoya University, Furo-cho Chikusa-ku, Nagoya 464-01, Japan
| | - Yutaka Shibata
- Institute for Laser Technology, Utsubo-Hommachi 1-8-4 Nishi-ku, Osaka 550, Japan Department of Biophysics, Graduate School of Science Kyoto University, Sakyo-ku, Kyoto 601-01, Japan Department of Physics, Graduate School of Science Nagoya University, Furo-cho Chikusa-ku, Nagoya 464-01, Japan
| | - Shuji Tachibanaki
- Institute for Laser Technology, Utsubo-Hommachi 1-8-4 Nishi-ku, Osaka 550, Japan Department of Biophysics, Graduate School of Science Kyoto University, Sakyo-ku, Kyoto 601-01, Japan Department of Physics, Graduate School of Science Nagoya University, Furo-cho Chikusa-ku, Nagoya 464-01, Japan
| | - Hideki Kandori
- Institute for Laser Technology, Utsubo-Hommachi 1-8-4 Nishi-ku, Osaka 550, Japan Department of Biophysics, Graduate School of Science Kyoto University, Sakyo-ku, Kyoto 601-01, Japan Department of Physics, Graduate School of Science Nagoya University, Furo-cho Chikusa-ku, Nagoya 464-01, Japan
| | - Yoshinori Shichida
- Institute for Laser Technology, Utsubo-Hommachi 1-8-4 Nishi-ku, Osaka 550, Japan Department of Biophysics, Graduate School of Science Kyoto University, Sakyo-ku, Kyoto 601-01, Japan Department of Physics, Graduate School of Science Nagoya University, Furo-cho Chikusa-ku, Nagoya 464-01, Japan
| | - Tetsuji Okada
- Institute for Laser Technology, Utsubo-Hommachi 1-8-4 Nishi-ku, Osaka 550, Japan Department of Biophysics, Graduate School of Science Kyoto University, Sakyo-ku, Kyoto 601-01, Japan Department of Physics, Graduate School of Science Nagoya University, Furo-cho Chikusa-ku, Nagoya 464-01, Japan
| | - Tsutomu Kouyama
- Institute for Laser Technology, Utsubo-Hommachi 1-8-4 Nishi-ku, Osaka 550, Japan Department of Biophysics, Graduate School of Science Kyoto University, Sakyo-ku, Kyoto 601-01, Japan Department of Physics, Graduate School of Science Nagoya University, Furo-cho Chikusa-ku, Nagoya 464-01, Japan
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Jäger F, Lou J, Nakanishi K, Ujj L, Atkinson GH. Vibrational Spectroscopy of a Picosecond, Structurally-Restricted Intermediate Containing a Seven-Membered Ring in the Room-Temperature Photoreaction of an Artificial Rhodopsin. J Am Chem Soc 1998. [DOI: 10.1021/ja972560c] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- F. Jäger
- Contribution from the Department of Chemistry and Optical Science Center, University of Arizona, Tucson, Arizona 85721, and Department of Chemistry, Columbia University, New York, New York 10027
| | - Jihong Lou
- Contribution from the Department of Chemistry and Optical Science Center, University of Arizona, Tucson, Arizona 85721, and Department of Chemistry, Columbia University, New York, New York 10027
| | - Koji Nakanishi
- Contribution from the Department of Chemistry and Optical Science Center, University of Arizona, Tucson, Arizona 85721, and Department of Chemistry, Columbia University, New York, New York 10027
| | - L. Ujj
- Contribution from the Department of Chemistry and Optical Science Center, University of Arizona, Tucson, Arizona 85721, and Department of Chemistry, Columbia University, New York, New York 10027
| | - G. H. Atkinson
- Contribution from the Department of Chemistry and Optical Science Center, University of Arizona, Tucson, Arizona 85721, and Department of Chemistry, Columbia University, New York, New York 10027
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F. Jäger,, Ujj L, Atkinson GH. Vibrational Spectrum of Bathorhodopsin in the Room-Temperature Rhodopsin Photoreaction. J Am Chem Soc 1997. [DOI: 10.1021/ja9715298] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- F. Jäger,
- Contribution from the Department of Chemistry and Optical Science Center, University of Arizona, Tucson, Arizona 85721
| | - L. Ujj
- Contribution from the Department of Chemistry and Optical Science Center, University of Arizona, Tucson, Arizona 85721
| | - G. H. Atkinson
- Contribution from the Department of Chemistry and Optical Science Center, University of Arizona, Tucson, Arizona 85721
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30
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Garavelli M, Celani P, Bernardi F, Robb MA, Olivucci M. The C5H6NH2+Protonated Shiff Base: Anab InitioMinimal Model for Retinal Photoisomerization. J Am Chem Soc 1997. [DOI: 10.1021/ja9610895] [Citation(s) in RCA: 237] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Strassburger JM, Gärtner W, Braslavsky SE. Volume and enthalpy changes after photoexcitation of bovine rhodopsin: laser-induced optoacoustic studies. Biophys J 1997; 72:2294-303. [PMID: 9129833 PMCID: PMC1184425 DOI: 10.1016/s0006-3495(97)78874-x] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
Laser-induced optoacoustic measurements were performed with bovine rhodopsin in the temperature range 5-32 degrees C in its natural environment (i.e., in washed membranes) as well as solubilized in dodecyl-beta-D-maltoside. A signal deconvolution procedure using a simple sequential kinetic scheme for the photobaric time evolution revealed, in the case of the washed membranes, the presence of an intermediate with a 14-ns lifetime at 25 degrees C, of the same order as that reported for the BSI intermediate in solubilized rhodopsin (Hug, S. J., W. J. Lewis, C. M. Einterz, T. E. Thorgeirsson, and D. S. Kliger. 1990. Nanosecond photolysis of rhodopsin: evidence for a new, blue-shifted intermediate. Biochemistry. 29:1475-1485), with an energy content of (85 +/- 20) kJ/mol, and accompanied by an expansion of 26 +/- 3 ml/mol. The difference in energy content between BSI and the next transient lumi was estimated in only -1 +/- 5 kJ/mol, concomitant with an expansion of 9 +/- 3 ml/mol. Thus, this transition, which according to literature involves an equilibrium, should be controlled by an entropic change, rather than by an enthalpic difference. This is supported by the fact that both activation parameters for the decay of batho and BSI decrease upon solubilization. For detergent-solubilized rhodopsin, two time constants were enough to fit the sample signal. A short lifetime ascribable to BSI was not detected in this case. For the first intermediate (probably batho in equilibrium with BSI), an energy content of 50 +/- 20 kJ/mol and an expansion of 20 +/- 1 ml/mol, and for lumi an energy content of 11 +/- 20 kJ/mol and a further expansion of 11 +/- 2 ml/mol were determined. Thus, the intermediates of the membrane-embedded form of rhodopsin (in contrast to solubilized samples) are kept in a higher energy level, although the total expansion from rhodopsin to lumi is similar for both conditions (35 +/- 6 and 31 +/- 3 ml/mol). The expansions are interpreted as protein reorganization processes as a consequence of the photoisomerization of the chromophore. As a result, weak interactions are probably perturbed and the protein gains conformational flexibility.
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Affiliation(s)
- J M Strassburger
- Max-Planck-Institut für Strahlenchernie, Mülheim an der Ruhr, Germany
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Real-Time Detection of 60-fs Isomerization in a Rhodopsin Analog Containing Eight-Membered-Ring Retinal. J Am Chem Soc 1996. [DOI: 10.1021/ja951665h] [Citation(s) in RCA: 58] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Delaney JK, Brack TL, Atkinson GH, Ottolenghi M, Steinberg G, Sheves M. Primary picosecond molecular events in the photoreaction of the BR5.12 artificial bacteriorhodopsin pigment. Proc Natl Acad Sci U S A 1995; 92:2101-5. [PMID: 7892231 PMCID: PMC42431 DOI: 10.1073/pnas.92.6.2101] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
Abstract
The picosecond dynamics of the photoreaction of an artificial bacteriorhodopsin (BR) pigment containing a retinal in which a five-membered ring spans the C-12 to C-14 positions of the polyene chain (BR5.12) is examined by using time-resolved absorption and fluorescence and resonance Raman spectroscopy. The ring within the retinal chromophore of BR5.12 blocks the C-13 = C-14 isomerization proposed to be a primary step in the energy storage/transduction mechanism in the BR photocycle. Relative to the native BR pigment (BR-570), the absorption spectrum of BR5.12 is red-shifted by 8 nm. The fluorescence spectrum of BR5.12 closely resembles that of BR-570 although the relative fluorescence yield is higher (approximately 10-fold). Picosecond transient absorption (4-ps pulses, 568-662 nm) measurements reveal an intermediate absorbing to the red side of BR5.12. Kinetic fits show that the red-absorbing intermediate appears within < 3 ps and decays with a time constant of 17 +/- 1 ps to form only BR5.12. No emission in the 650- to 900-nm region can be attributed to the red-absorbing species. Since rotation around C-12 - C-13 and isomerization around C-13 = C-14 are prevented in BR5.12, these results demonstrate that motion in these regions of the retinal is (i) necessary to form the K-like intermediate observed in the native BR-570 photocycle and (ii) not necessary to form a red-absorbing intermediate that has spectral and kinetic properties analogous to those of J-625 in the native BR photocycle. Discussions of the excited and ground electronic state assignments for the intermediate observed in the BR5.12 photoreaction are presented.
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Affiliation(s)
- J K Delaney
- Department of Chemistry, University of Arizona, Tucson 85721
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Imai H, Mizukami T, Imamoto Y, Shichida Y. Direct observation of the thermal equilibria among lumirhodopsin, metarhodopsin I, and metarhodopsin II in chicken rhodopsin. Biochemistry 1994; 33:14351-8. [PMID: 7947845 DOI: 10.1021/bi00251a049] [Citation(s) in RCA: 25] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Using low-temperature time-resolved spectroscopy, we have directly observed thermal back reaction of metarhodopsin I (meta I) to lumirhodopsin (lumi) and that of metarhodopsin II (meta II) to meta I in chicken rhodopsin to demonstrate the presence of thermal equilibria among lumi, meta I, and meta II. The back reaction from meta I to lumi was observed when the rhodopsin sample irradiated at -35 degrees C was warmed to -20 degrees C, while that from meta II to meta I was observed when the sample irradiated at -10 degrees C was cooled to -20 degrees C. Thermodynamic parameters of lumi, meta I, and meta II were calculated from the equilibrium constants estimated by analyzing the spectra of the equilibrium states at temperatures ranging from -30 to -10 degrees C. The results showed that meta I has an enthalpy and an entropy considerably smaller than those of lumi and meta II, while the difference in thermodynamic parameters between lumi and meta II is not so large. These results suggest that meta I is a crucial stage of conversion of the light energy captured by the chromophore into restricted conformations of the chromophore and/or protein, from which a large conformational change of the protein starts to form meta II.
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Affiliation(s)
- H Imai
- Department of Biophysics, Faculty of Science, Kyoto University, Japan
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Derguini F, Nakanishi K, Hämmerling U, Buck J. Intracellular signaling activity of synthetic (14R)-, (14S)-, and (14RS)-14-hydroxy-4,14-retro-retinol. Biochemistry 1994; 33:623-8. [PMID: 8292589 DOI: 10.1021/bi00169a001] [Citation(s) in RCA: 41] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
14-Hydroxy-4,14-retro-retinol (14-HRR), first isolated from cultures of lymphoblastoid 5/2 and HeLa cells and characterized by NMR, UV, and CD, is a metabolite of retinol which promotes growth of B lymphocytes in culture and activation of T lymphocytes by antigen receptor-mediated signals. It is also produced by various tested cell lines: fibroblasts, leukemia, and Drosophila cells. 14-HRR is the first bioactive retro-retinoid to be discovered and, after retinal and retinoic acid, is the third intracellular messenger molecule derived from retinol. Physical properties and intracellular signaling activities of synthetic (14R)-HRR, (14S)-HRR, and racemic 14-HRR are described. CD spectra indicate that natural 14-HRR isolated previously was a mixture of enantiomers. B-cell survival and T-cell activation assays performed in the optimal range of (7-1.6) x 10(-7) M surprisingly showed that all 14-HRR compounds exhibit similar activity, with the 14R enantiomer exhibiting slightly higher activity in comparison to the 14S enantiomer. However, because of the semiquantitative nature of the assays, the conclusion as to which enantiomer is more active and which is the true ligand for the target receptor must await characterization of this protein.
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Affiliation(s)
- F Derguini
- Department of Chemistry, Columbia University, New York, New York 10027
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Hu S, Franklin PJ, Wang J, Ruiz Silva BE, Derguini F, Nakanishi K, Chen AH. Unbleachable rhodopsin with an 11-cis-locked eight-membered ring retinal: the visual transduction process. Biochemistry 1994; 33:408-16. [PMID: 8286371 DOI: 10.1021/bi00168a004] [Citation(s) in RCA: 59] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Visual transduction occurs through photorhodopsin, the primary photoproduct of rhodopsin, which relaxes to bathorhodopsin and a series of other intermediates until it reaches the metarhodopsin II stage, upon which the enzymatic cascade leading to vision is activated. Despite advances in areas related to visual transduction, the triggering process itself, a key problem in the chemistry of rhodopsin, has remained unsolved. In order to clarify the extent of involvement of the chromophoric excited state versus the 11-cis to trans isomerization, and as an extension of past studies with 11-cis-locked seven-membered ring rhodopsin (Rh7), 11-cis eight- and nine-membered ring retinal analogs, ret8 and ret9, respectively, have been synthesized. The bulkiness of the tetramethylene bridge in ret8 led to numerous unexpected obstacles in attempts to reconstitute a ret8-containing rhodopsin (Rh8) embedded in lipid bilayer membranes. These obstacles were solved by using methylated rhodopsin which gave MeRh8 containing 11-cis-ret8 as its chromophore. MeRh8 exhibited UV-vis and CD spectra very similar to those of native rhodopsin (Rh); furthermore, the quantum efficiency of photorhodopsin formation was comparable to that of Rh.(ABSTRACT TRUNCATED AT 250 WORDS)
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Affiliation(s)
- S Hu
- Department of Chemistry, Columbia University, New York, New York 10027
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