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van Wilderen LJGW, Kern-Michler D, Neumann C, Reinfelds M, von Cosel J, Horz M, Burghardt I, Heckel A, Bredenbeck J. Choose your leaving group: selective photodeprotection in a mixture of pHP-caged compounds by VIPER excitation. Chem Sci 2023; 14:2624-2630. [PMID: 36908963 PMCID: PMC9993852 DOI: 10.1039/d2sc06259c] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2022] [Accepted: 02/07/2023] [Indexed: 02/11/2023] Open
Abstract
Photocages are light-triggerable molecular moieties that can locally release a pre-determined leaving group (LG). Finding a suitable photocage for a particular application may be challenging, as the choice may be limited by for instance the optical or physicochemical properties of the system. Using more than one photocage to release different LGs in a reaction mixture may even be more difficult. In this work an experimental strategy is presented that allows us to hand-pick the release of different LGs, and to do so in any order. This is achieved by using isotopologue photocage-LG mixtures in combination with ultrafast VIbrationally Promoted Electronic Resonance (VIPER) excitation. The latter provides the required molecular selectivity simply by tuning the wavenumber of the used IR pulses to the resonance of a specific photocage isotopologue, as is demonstrated here for the para-hydroxyphenacyl (pHP) photocage. For spectroscopic convenience, we use isotopologues of the infrared (IR) spectroscopic marker -SCN as different LGs. Especially for applications where fast LG release is required, pHP is found to be an excellent candidate, as free LG formation is observed to occur with a 10 ps lifetime. The devised strategy may open up new complex uncaging applications, where multiple LGs can be formed locally on a short time scale and in any sequence.
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Affiliation(s)
- Luuk J G W van Wilderen
- Johann Wolfgang Goethe-University, Institute of Biophysics Max-von-Laue-Str. 1 60438 Frankfurt am Main Germany
| | - Daniela Kern-Michler
- Johann Wolfgang Goethe-University, Institute of Biophysics Max-von-Laue-Str. 1 60438 Frankfurt am Main Germany
| | - Carsten Neumann
- Johann Wolfgang Goethe-University, Institute of Biophysics Max-von-Laue-Str. 1 60438 Frankfurt am Main Germany
| | - Matiss Reinfelds
- Johann Wolfgang Goethe-University, Institute of Organic Chemistry and Chemical Biology Max-von-Laue-Str. 7 60438 Frankfurt am Main Germany
| | - Jan von Cosel
- Johann Wolfgang Goethe-University, Institute of Physical and Theoretical Chemistry Max-von-Laue-Str. 7 60438 Frankfurt am Main Germany
| | - Maximiliane Horz
- Johann Wolfgang Goethe-University, Institute of Physical and Theoretical Chemistry Max-von-Laue-Str. 7 60438 Frankfurt am Main Germany
| | - Irene Burghardt
- Johann Wolfgang Goethe-University, Institute of Physical and Theoretical Chemistry Max-von-Laue-Str. 7 60438 Frankfurt am Main Germany
| | - Alexander Heckel
- Johann Wolfgang Goethe-University, Institute of Organic Chemistry and Chemical Biology Max-von-Laue-Str. 7 60438 Frankfurt am Main Germany
| | - Jens Bredenbeck
- Johann Wolfgang Goethe-University, Institute of Biophysics Max-von-Laue-Str. 1 60438 Frankfurt am Main Germany
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Horz M, Masood HMA, Brunst H, Cerezo J, Picconi D, Vormann H, Niraghatam MS, van Wilderen LJGW, Bredenbeck J, Santoro F, Burghardt I. Vibrationally resolved two-photon electronic spectra including vibrational pre-excitation: Theory and application to VIPER spectroscopy with two-photon excitation. J Chem Phys 2023; 158:064201. [PMID: 36792506 DOI: 10.1063/5.0132608] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023] Open
Abstract
Following up on our previous work on vibrationally resolved electronic absorption spectra including the effect of vibrational pre-excitation [von Cosel et al., J. Chem. Phys. 147, 164116 (2017)], we present a combined theoretical and experimental study of two-photon-induced vibronic transitions in polyatomic molecules that are probed in the VIbrationally Promoted Electronic Resonance experiment using two-photon excitation (2P-VIPER). In order to compute vibronic spectra, we employ time-independent and time-dependent methods based on the evaluation of Franck-Condon overlap integrals and Fourier transformations of time-domain correlation functions, respectively. The time-independent approach uses a generalized version of the FCclasses method, while the time-dependent approach relies on the analytical evaluation of Gaussian moments within the harmonic approximation, including Duschinsky rotation effects. For the Coumarin 6 dye, two-dimensional 2P-VIPER experiments involving excitation to the lowest-lying singlet excited state (S1) are presented and compared with corresponding one-photon VIPER spectra. In both cases, coumarin ring modes and a CO stretch mode show VIPER activity, albeit with different relative intensities. Selective pre-excitation of these modes leads to a pronounced redshift of the low-frequency edge of the electronic absorption spectrum, which is a prerequisite for the VIPER experiment. Theoretical analysis underscores the role of interference between Franck-Condon and Herzberg-Teller effects in the two-photon experiment, which is at the root of the observed intensity distribution.
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Affiliation(s)
- Maximiliane Horz
- Institute of Physical and Theoretical Chemistry, Goethe University Frankfurt, Max-von-Laue-Str. 7, 60438 Frankfurt, Germany
| | - Hafiz M A Masood
- Institute of Biophysics, Goethe University Frankfurt, Max-von-Laue-Str. 1, 60438 Frankfurt, Germany
| | - Hendrik Brunst
- Institute of Biophysics, Goethe University Frankfurt, Max-von-Laue-Str. 1, 60438 Frankfurt, Germany
| | - Javier Cerezo
- Departamento de Química and Institute for Advanced Research in Chemical Sciences (IAdChem), Universidad Autónoma de Madrid, 28049 Madrid, Spain
| | - David Picconi
- Institute of Physical and Theoretical Chemistry, Goethe University Frankfurt, Max-von-Laue-Str. 7, 60438 Frankfurt, Germany
| | - Hannah Vormann
- Institute of Physical and Theoretical Chemistry, Goethe University Frankfurt, Max-von-Laue-Str. 7, 60438 Frankfurt, Germany
| | - Madhava Shyam Niraghatam
- Institute of Physical and Theoretical Chemistry, Goethe University Frankfurt, Max-von-Laue-Str. 7, 60438 Frankfurt, Germany
| | - Luuk J G W van Wilderen
- Institute of Biophysics, Goethe University Frankfurt, Max-von-Laue-Str. 1, 60438 Frankfurt, Germany
| | - Jens Bredenbeck
- Institute of Biophysics, Goethe University Frankfurt, Max-von-Laue-Str. 1, 60438 Frankfurt, Germany
| | - Fabrizio Santoro
- Consiglio Nazionale delle Ricerche - CNR, Istituto di Chimica dei Composti Organo Metallici (ICCOM-CNR), SS di Pisa, Via G. Moruzzi 1, I-56124 Pisa, Italy
| | - Irene Burghardt
- Institute of Physical and Theoretical Chemistry, Goethe University Frankfurt, Max-von-Laue-Str. 7, 60438 Frankfurt, Germany
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van Wilderen LJGW, Blankenburg L, Bredenbeck J. Femtosecond-to-millisecond mid-IR spectroscopy of Photoactive Yellow Protein uncovers structural micro-transitions of the chromophore's protonation mechanism. J Chem Phys 2022; 156:205103. [DOI: 10.1063/5.0091918] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
Protein structural dynamics can span many orders of magnitude in time. Photoactive Yellow Protein's (PYP) reversible photocycle encompasses picosecond isomerization of the light-absorbing chromophore as well as large scale protein backbone motions occurring on a millisecond timescale. Femtosecond-to-millisecond time-resolved mid-Infrared (IR) spectroscopy is employed here to uncover structural details of photocycle intermediates up to chromophore protonation and the first structural changes leading to formation of the partially-unfolded signalling state pB. The data show that a commonly thought stable transient photocycle intermediate is actually formed after a sequence of several smaller structural changes. We provide residue-specific spectroscopic evidence that protonation of the chromophore on a hundreds of microseconds timescale is delayed with respect to deprotonation of the nearby E46 residue. That implies that the direct proton donor is not E46 but most likely a water molecule. Such details may assist ongoing photocycle and protein folding simulation efforts on the complex and wide time-spanning photocycle of the model system PYP.
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Fischer T, van Wilderen LJGW, Gnau P, Bredenbeck J, Essen LO, Wachtveitl J, Slavov C. Ultrafast Photoconversion Dynamics of the Knotless Phytochrome SynCph2. Int J Mol Sci 2021; 22:ijms221910690. [PMID: 34639031 PMCID: PMC8508867 DOI: 10.3390/ijms221910690] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2021] [Revised: 09/24/2021] [Accepted: 09/28/2021] [Indexed: 12/03/2022] Open
Abstract
The family of phytochrome photoreceptors contains proteins with different domain architectures and spectral properties. Knotless phytochromes are one of the three main subgroups classified by their distinct lack of the PAS domain in their photosensory core module, which is in contrast to the canonical PAS-GAF-PHY array. Despite intensive research on the ultrafast photodynamics of phytochromes, little is known about the primary kinetics in knotless phytochromes. Here, we present the ultrafast Pr ⇆ Pfr photodynamics of SynCph2, the best-known knotless phytochrome. Our results show that the excited state lifetime of Pr* (~200 ps) is similar to bacteriophytochromes, but much longer than in most canonical phytochromes. We assign the slow Pr* kinetics to relaxation processes of the chromophore-binding pocket that controls the bilin chromophore’s isomerization step. The Pfr photoconversion dynamics starts with a faster excited state relaxation than in canonical phytochromes, but, despite the differences in the respective domain architectures, proceeds via similar ground state intermediate steps up to Meta-F. Based on our observations, we propose that the kinetic features and overall dynamics of the ultrafast photoreaction are determined to a great extent by the geometrical context (i.e., available space and flexibility) within the binding pocket, while the general reaction steps following the photoexcitation are most likely conserved among the red/far-red phytochromes.
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Affiliation(s)
- Tobias Fischer
- Institute of Physical and Theoretical Chemistry, Goethe University Frankfurt am Main, Max-von-Laue Straße 7, 60438 Frankfurt, Germany;
| | - Luuk J. G. W. van Wilderen
- Institute of Biophysics, Goethe University Frankfurt am Main, Max-von-Laue Straße 1, 60438 Frankfurt, Germany; (L.J.G.W.v.W.); (J.B.)
| | - Petra Gnau
- Department of Chemistry, Philipps-Universität Marburg, Hans-Meerwein-Straße 4, 35032 Marburg, Germany; (P.G.); (L.-O.E.)
| | - Jens Bredenbeck
- Institute of Biophysics, Goethe University Frankfurt am Main, Max-von-Laue Straße 1, 60438 Frankfurt, Germany; (L.J.G.W.v.W.); (J.B.)
| | - Lars-Oliver Essen
- Department of Chemistry, Philipps-Universität Marburg, Hans-Meerwein-Straße 4, 35032 Marburg, Germany; (P.G.); (L.-O.E.)
- Center for Synthetic Microbiology, Philipps-Universität Marburg, Hans-Meerwein-Straße 6, 35032 Marburg, Germany
| | - Josef Wachtveitl
- Institute of Physical and Theoretical Chemistry, Goethe University Frankfurt am Main, Max-von-Laue Straße 7, 60438 Frankfurt, Germany;
- Correspondence: (J.W.); (C.S.)
| | - Chavdar Slavov
- Institute of Physical and Theoretical Chemistry, Goethe University Frankfurt am Main, Max-von-Laue Straße 7, 60438 Frankfurt, Germany;
- Correspondence: (J.W.); (C.S.)
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5
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El Khoury Y, Le Breton G, Cunha AV, Jansen TLC, van Wilderen LJGW, Bredenbeck J. Lessons from combined experimental and theoretical examination of the FTIR and 2D-IR spectroelectrochemistry of the amide I region of cytochrome c. J Chem Phys 2021; 154:124201. [PMID: 33810651 DOI: 10.1063/5.0039969] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
Amide I difference spectroscopy is widely used to investigate protein function and structure changes. In this article, we show that the common approach of assigning features in amide I difference signals to distinct secondary structure elements in many cases may not be justified. Evidence comes from Fourier transform infrared (FTIR) and 2D-IR spectroelectrochemistry of the protein cytochrome c in the amide I range, in combination with computational spectroscopy based on molecular dynamics (MD) simulations. This combination reveals that each secondary structure unit, such as an alpha-helix or a beta-sheet, exhibits broad overlapping contributions, usually spanning a large part of the amide I region, which in the case of difference absorption experiments (such as in FTIR spectroelectrochemistry) may lead to intensity-compensating and even sign-changing contributions. We use cytochrome c as the test case, as this small electron-transferring redox-active protein contains different kinds of secondary structure units. Upon switching its redox-state, the protein exhibits a different charge distribution while largely retaining its structural scaffold. Our theoretical analysis suggests that the change in charge distribution contributes to the spectral changes and that structural changes are small. However, in order to confidently interpret FTIR amide I difference signals in cytochrome c and proteins in general, MD simulations in combination with additional experimental approaches such as isotope labeling, the insertion of infrared labels to selectively probe local structural elements will be required. In case these data are not available, a critical assessment of previous interpretations of protein amide I 1D- and 2D-IR difference spectroscopy data is warranted.
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Affiliation(s)
- Youssef El Khoury
- Institut für Biophysik, Johann-Wolfgang-Goethe-Universität, Max-von-Laue-Strasse. 1, 60438 Frankfurt am Main, Germany
| | - Guillaume Le Breton
- University of Groningen, Zernike Institute for Advanced Materials, Nijenborgh 4, 9747 AG Groningen, The Netherlands
| | - Ana V Cunha
- University of Groningen, Zernike Institute for Advanced Materials, Nijenborgh 4, 9747 AG Groningen, The Netherlands
| | - Thomas L C Jansen
- University of Groningen, Zernike Institute for Advanced Materials, Nijenborgh 4, 9747 AG Groningen, The Netherlands
| | - Luuk J G W van Wilderen
- Institut für Biophysik, Johann-Wolfgang-Goethe-Universität, Max-von-Laue-Strasse. 1, 60438 Frankfurt am Main, Germany
| | - Jens Bredenbeck
- Institut für Biophysik, Johann-Wolfgang-Goethe-Universität, Max-von-Laue-Strasse. 1, 60438 Frankfurt am Main, Germany
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6
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Schmidt-Engler JM, Blankenburg L, Błasiak B, van Wilderen LJGW, Cho M, Bredenbeck J. Vibrational Lifetime of the SCN Protein Label in H 2O and D 2O Reports Site-Specific Solvation and Structure Changes During PYP's Photocycle. Anal Chem 2019; 92:1024-1032. [PMID: 31769286 DOI: 10.1021/acs.analchem.9b03997] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
The application of vibrational labels such as thiocyanate (-S-C≡N) for studying protein structure and dynamics is thriving. Absorption spectroscopy is usually employed to obtain wavenumber and line shape of the label. An observable of great significance might be the vibrational lifetime, which can be obtained by pump probe or 2D-IR spectroscopy. Due to the insulating effect of the heavy sulfur atom in the case of the SCN label, the lifetime of the C≡N oscillator is expected to be particularly sensitive to its surrounding as it is not dominated by through-bond relaxation. We therefore investigate the vibrational lifetime of the SCN label at various positions in the blue light sensor protein Photoactive Yellow Protein (PYP) in the ground state and signaling state of the photoreceptor. We find that the vibrational lifetime of the C≡N stretching mode is strongly affected both by its protein environment and by the degree of exposure to the solvent. Even for label positions where the line shape and wavenumber observed by FTIR are barely changing upon activation of the photoreceptor, we find that the lifetime can change considerably. To obtain an unambiguous measure for the solvent exposure of the labeled site, we show that it is imperative to compare the lifetimes in H2O and D2O. Importantly, the lifetimes shorten in H2O as compared to D2O for water exposed labels, while they stay largely the same for buried labels. We quantify this effect by defining a solvent exclusion coefficient (SEC). The response of the label's vibrational lifetime to its solvent exposure renders it a suitable universal probe for protein investigations. This applies even to systems that are otherwise hard to address, such as transient or short-lived states, which could be created during a protein's working cycle (as here in PYP) or during protein folding. It is also applicable to flexible systems (intrinsically disordered proteins), protein-protein and protein-membrane interactions.
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Affiliation(s)
- Julian M Schmidt-Engler
- Johann Wolfgang Goethe-University , Institute of Biophysics , Max-von-Laue-Straße 1 , 60438 Frankfurt am Main , Germany
| | - Larissa Blankenburg
- Johann Wolfgang Goethe-University , Institute of Biophysics , Max-von-Laue-Straße 1 , 60438 Frankfurt am Main , Germany
| | - Bartosz Błasiak
- Johann Wolfgang Goethe-University , Institute of Biophysics , Max-von-Laue-Straße 1 , 60438 Frankfurt am Main , Germany
| | - Luuk J G W van Wilderen
- Johann Wolfgang Goethe-University , Institute of Biophysics , Max-von-Laue-Straße 1 , 60438 Frankfurt am Main , Germany
| | - Minhaeng Cho
- Institute of Basic Science , Center of Molecular Spectroscopy and Dynamics , 145 Anam-ro , Seongbuk-gu , Seoul 02841 , Republic of Korea.,Korea University , Department of Chemistry , 145 Anam-ro , Seongbuk-gu , Seoul 02841 , Republic of Korea
| | - Jens Bredenbeck
- Johann Wolfgang Goethe-University , Institute of Biophysics , Max-von-Laue-Straße 1 , 60438 Frankfurt am Main , Germany
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7
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Kern-Michler D, Neumann C, Mielke N, van Wilderen LJGW, Reinfelds M, von Cosel J, Santoro F, Heckel A, Burghardt I, Bredenbeck J. Controlling Photochemistry via Isotopomers and IR Pre-excitation. J Am Chem Soc 2018; 140:926-931. [PMID: 29182322 DOI: 10.1021/jacs.7b08723] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
It is a photochemist's dream to be able to photoinduce a reaction of a specific molecular species in an ensemble of similar but not identical ones. The problem is that similar molecules often exhibit nearly identical UV-Vis absorption spectra, making them difficult or impossible to distinguish or to select spectroscopically. The ultrafast VIPER (VIbrationally Promoted Electronic Resonance) pulse sequence allows to pick a single species for electronic excitation based on its infrared spectrum. The latter usually shows more features, allowing the discrimination between species than the UV-Vis spectrum. Here, we show that it is possible to induce and monitor species-selective photochemistry even for molecules with virtually identical UV-Vis spectra, which is the case for isotopomers. Next to isotope-selective photochemistry in solution, applications to orthogonal photo-uncaging and species-selective spectroscopy and photochemistry in mixtures are within reach.
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Affiliation(s)
- Daniela Kern-Michler
- Institute of Biophysics, Goethe University Frankfurt , Max-von-Laue-Str. 1, 60438 Frankfurt am Main, Germany
| | - Carsten Neumann
- Institute of Biophysics, Goethe University Frankfurt , Max-von-Laue-Str. 1, 60438 Frankfurt am Main, Germany
| | - Nicole Mielke
- Institute of Biophysics, Goethe University Frankfurt , Max-von-Laue-Str. 1, 60438 Frankfurt am Main, Germany
| | - Luuk J G W van Wilderen
- Institute of Biophysics, Goethe University Frankfurt , Max-von-Laue-Str. 1, 60438 Frankfurt am Main, Germany
| | - Matiss Reinfelds
- Institute of Organic Chemistry and Chemical Biology, Goethe University Frankfurt , Max-von-Laue-Str. 7, 60438 Frankfurt am Main, Germany
| | - Jan von Cosel
- Institute of Physical and Theoretical Chemistry, Goethe University Frankfurt , Max-von-Laue Str. 7, 60438 Frankfurt am Main, Germany
| | - Fabrizio Santoro
- Consiglio Nazionale delle Ricerche (CNR), Istituto di Chimica dei Composti Organo Metallici (ICCOM-CNR) , UOS di Pisa, Via G. Moruzzi 1, I-56124 Pisa, Italy
| | - Alexander Heckel
- Institute of Organic Chemistry and Chemical Biology, Goethe University Frankfurt , Max-von-Laue-Str. 7, 60438 Frankfurt am Main, Germany
| | - Irene Burghardt
- Institute of Physical and Theoretical Chemistry, Goethe University Frankfurt , Max-von-Laue Str. 7, 60438 Frankfurt am Main, Germany
| | - Jens Bredenbeck
- Institute of Biophysics, Goethe University Frankfurt , Max-von-Laue-Str. 1, 60438 Frankfurt am Main, Germany
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8
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von Cosel J, Cerezo J, Kern-Michler D, Neumann C, van Wilderen LJGW, Bredenbeck J, Santoro F, Burghardt I. Vibrationally resolved electronic spectra including vibrational pre-excitation: Theory and application to VIPER spectroscopy. J Chem Phys 2017; 147:164116. [DOI: 10.1063/1.4999455] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Affiliation(s)
- Jan von Cosel
- Institute of Physical and Theoretical Chemistry, Goethe University Frankfurt, Max-von-Laue-Str. 7, 60438 Frankfurt, Germany
| | - Javier Cerezo
- Departamento de Química Física, Universidad de Murcia, E-30071 Murcia, Spain
| | - Daniela Kern-Michler
- Institute of Biophysics, Goethe University Frankfurt, Max-von-Laue-Str. 1, 60438 Frankfurt, Germany
| | - Carsten Neumann
- Institute of Biophysics, Goethe University Frankfurt, Max-von-Laue-Str. 1, 60438 Frankfurt, Germany
| | | | - Jens Bredenbeck
- Institute of Biophysics, Goethe University Frankfurt, Max-von-Laue-Str. 1, 60438 Frankfurt, Germany
| | - Fabrizio Santoro
- Consiglio Nazionale delle Ricerche–CNR, Istituto di Chimica dei Composti Organo Metallici (ICCOM-CNR), UOS di Pisa, Via G. Moruzzi 1, I-56124 Pisa, Italy
| | - Irene Burghardt
- Institute of Physical and Theoretical Chemistry, Goethe University Frankfurt, Max-von-Laue-Str. 7, 60438 Frankfurt, Germany
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van Wilderen LJGW, Kern-Michler D, Müller-Werkmeister HM, Bredenbeck J. Correction: Vibrational dynamics and solvatochromism of the label SCN in various solvents and hemoglobin by time dependent IR and 2D-IR spectroscopy. Phys Chem Chem Phys 2017; 19:9676-9678. [PMID: 28349151 DOI: 10.1039/c7cp90063e] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Correction for 'Vibrational dynamics and solvatochromism of the label SCN in various solvents and hemoglobin by time dependent IR and 2D-IR spectroscopy' by Luuk J. G. W. van Wilderen et al., Phys. Chem. Chem. Phys., 2014, 16, 19643-19653.
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Affiliation(s)
- Luuk J G W van Wilderen
- Johann Wolfgang Goethe-University, Institute of Biophysics, Max-von-Laue-Str. 1, 60438, Frankfurt am Main, Germany.
| | - Daniela Kern-Michler
- Johann Wolfgang Goethe-University, Institute of Biophysics, Max-von-Laue-Str. 1, 60438, Frankfurt am Main, Germany.
| | - Henrike M Müller-Werkmeister
- Johann Wolfgang Goethe-University, Institute of Biophysics, Max-von-Laue-Str. 1, 60438, Frankfurt am Main, Germany.
| | - Jens Bredenbeck
- Johann Wolfgang Goethe-University, Institute of Biophysics, Max-von-Laue-Str. 1, 60438, Frankfurt am Main, Germany.
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van Wilderen LJGW, Silkstone G, Mason M, van Thor JJ, Wilson MT. Kinetic studies on the oxidation of semiquinone and hydroquinone forms of Arabidopsis cryptochrome by molecular oxygen. FEBS Open Bio 2015; 5:885-92. [PMID: 26649273 PMCID: PMC4643184 DOI: 10.1016/j.fob.2015.10.007] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2015] [Revised: 10/18/2015] [Accepted: 10/20/2015] [Indexed: 11/29/2022] Open
Abstract
The flavin chromophore of the photoreceptor cryptochrome is reduced by light. The neutral flavin semiquinone is accumulated under anaerobic conditions. Fully-reduced flavin forms in presence of external reductant (anaerobic conditions). Stopped-flow experiments reveal light-independent recovery of the ground state. The dark recovery process requires molecular oxygen.
Cryptochromes (crys) are flavoprotein photoreceptors present throughout the biological kingdom that play important roles in plant development and entrainment of the circadian clock in several organisms. Crys non-covalently bind flavin adenine dinucleotide (FAD) which undergoes photoreduction from the oxidised state to a radical form suggested to be active in signalling in vivo. Although the photoreduction reactions have been well characterised by a number of approaches, little is known of the oxidation reactions of crys and their mechanisms. In this work, a stopped-flow kinetics approach is used to investigate the mechanism of cry oxidation in the presence and absence of an external electron donor. This in vitro study extends earlier investigations of the oxidation of Arabidopsis cryptochrome1 by molecular oxygen and demonstrates that, under some conditions, a more complex model for oxidation of the flavin than was previously proposed is required to accommodate the spectral evidence (see P. Müller and M. Ahmad (2011) J. Biol. Chem. 286, 21033–21040 [1]). In the absence of an electron donor, photoreduction leads predominantly to the formation of the radical FADH•. Dark recovery most likely forms flavin hydroperoxide (FADHOOH) requiring superoxide. In the presence of reductant (DTT), illumination yields the fully reduced flavin species (FADH−). Reaction of this with dioxygen leads to transient radical (FADH•) and simultaneous accumulation of oxidised species (FAD), possibly governed by interplay between different cryptochrome molecules or cooperativity effects within the cry homodimer.
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Affiliation(s)
- Luuk J G W van Wilderen
- Division of Molecular Biosciences, Faculty of Natural Sciences, South Kensington Campus, Imperial College London, London, United Kingdom
| | - Gary Silkstone
- Department of Biological Sciences, University of Essex, Wivenhoe Park, Colchester, United Kingdom
| | - Maria Mason
- Department of Biological Sciences, University of Essex, Wivenhoe Park, Colchester, United Kingdom
| | - Jasper J van Thor
- Division of Molecular Biosciences, Faculty of Natural Sciences, South Kensington Campus, Imperial College London, London, United Kingdom
| | - Michael T Wilson
- Department of Biological Sciences, University of Essex, Wivenhoe Park, Colchester, United Kingdom
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van Wilderen LJGW, Bredenbeck J. From Ultrafast Structure Determination to Steering Reactions: Mixed IR/Non-IR Multidimensional Vibrational Spectroscopies. Angew Chem Int Ed Engl 2015; 54:11624-40. [PMID: 26394274 DOI: 10.1002/anie.201503155] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2015] [Indexed: 12/27/2022]
Abstract
Ultrafast multidimensional infrared spectroscopy is a powerful method for resolving features of molecular structure and dynamics that are difficult or impossible to address with linear spectroscopy. Augmenting the IR pulse sequences by resonant or nonresonant UV, Vis, or NIR pulses considerably extends the range of application and creates techniques with possibilities far beyond a pure multidimensional IR experiment. These include surface-specific 2D-IR spectroscopy with sub-monolayer sensitivity, ultrafast structure determination in non-equilibrium systems, triggered exchange spectroscopy to correlate reactant and product bands, exploring the interplay of electronic and nuclear degrees of freedom, investigation of interactions between Raman- and IR-active modes, imaging with chemical contrast, sub-ensemble-selective photochemistry, and even steering a reaction by selective IR excitation. We give an overview of useful mixed IR/non-IR pulse sequences, discuss their differences, and illustrate their application potential.
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Affiliation(s)
| | - Jens Bredenbeck
- Institute of Biophysics, Johann Wolfgang Goethe-University, Frankfurt am Main (Germany).
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van Wilderen LJGW, Kern-Michler D, Müller-Werkmeister HM, Bredenbeck J. Vibrational dynamics and solvatochromism of the label SCN in various solvents and hemoglobin by time dependent IR and 2D-IR spectroscopy. Phys Chem Chem Phys 2014; 16:19643-53. [DOI: 10.1039/c4cp01498g] [Citation(s) in RCA: 82] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The vibrational label SCN is used to report on local structural dynamics in a protein revealing spectral diffusion on a picosecond scale. The SCN spectra are compared to the response of methylthiocyanate in solvents with different polarity and hydrogen-bonding capabilities.
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Affiliation(s)
| | - Daniela Kern-Michler
- Johann Wolfgang Goethe-University
- Institute of Biophysics
- Frankfurt am Main, Germany
| | | | - Jens Bredenbeck
- Johann Wolfgang Goethe-University
- Institute of Biophysics
- Frankfurt am Main, Germany
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13
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Fitzpatrick AE, Lincoln CN, van Wilderen LJGW, van Thor JJ. Pump–Dump–Probe and Pump–Repump–Probe Ultrafast Spectroscopy Resolves Cross Section of an Early Ground State Intermediate and Stimulated Emission in the Photoreactions of the Pr Ground State of the Cyanobacterial Phytochrome Cph1. J Phys Chem B 2012; 116:1077-88. [DOI: 10.1021/jp206298n] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Ann E. Fitzpatrick
- Division of Molecular Biosciences, Imperial College London, South Kensington, SW7 2AZ
| | - Craig N. Lincoln
- Division of Molecular Biosciences, Imperial College London, South Kensington, SW7 2AZ
| | | | - Jasper J. van Thor
- Division of Molecular Biosciences, Imperial College London, South Kensington, SW7 2AZ
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Di Donato M, van Wilderen LJGW, Van Stokkum IHM, Stuart TC, Kennis JTM, Hellingwerf KJ, van Grondelle R, Groot ML. Proton transfer events in GFP. Phys Chem Chem Phys 2011; 13:16295-305. [PMID: 21847481 DOI: 10.1039/c1cp20387h] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Proton transfer is one of the most important elementary processes in biology. Green fluorescent protein (GFP) serves as an important model system to elucidate the mechanistic details of this reaction, because in GFP proton transfer can be induced by light absorption. Illumination initiates proton transfer through a 'proton-wire', formed by the chromophore (the proton donor), water molecule W22, Ser205 and Glu222 (the acceptor), on a picosecond time scale. To obtain a more refined view of this process, we have used a combined approach of time resolved mid-infrared spectroscopy and visible pump-dump-probe spectroscopy to resolve with atomic resolution how and how fast protons move through this wire. Our results indicate that absorption of light by GFP induces in 3 ps (10 ps in D(2)O) a shift of the equilibrium positions of all protons in the H-bonded network, leading to a partial protonation of Glu222 and to a so-called low barrier hydrogen bond (LBHB) for the chromophore's proton, giving rise to dual emission at 475 and 508 nm. This state is followed by a repositioning of the protons on the wire in 10 ps (80 ps in D(2)O), ultimately forming the fully deprotonated chromophore and protonated Glu222.
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Affiliation(s)
- Mariangela Di Donato
- Department of Physics and Astronomy, VU University Amsterdam, De Boelelaan 1081, 1081 HV Amsterdam, The Netherlands.
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Abstract
Current advanced laser, optics and electronics technology allows sensitive recording of molecular dynamics, from single resonance to multi-colour and multi-pulse experiments. Extracting the occurring (bio-) physical relevant pathways via global analysis of experimental data requires a systematic investigation of connectivity schemes. Here we present a Matlab-based toolbox for this purpose. The toolbox has a graphical user interface which facilitates the application of different reaction models to the data to generate the coupled differential equations. Any time-dependent dataset can be analysed to extract time-independent correlations of the observables by using gradient or direct search methods. Specific capabilities (i.e. chirp and instrument response function) for the analysis of ultrafast pump-probe spectroscopic data are included. The inclusion of an extra pulse that interacts with a transient phase can help to disentangle complex interdependent pathways. The modelling of pathways is therefore extended by new theory (which is included in the toolbox) that describes the finite bleach (orientation) effect of single and multiple intense polarised femtosecond pulses on an ensemble of randomly oriented particles in the presence of population decay. For instance, the generally assumed flat-top multimode beam profile is adapted to a more realistic Gaussian shape, exposing the need for several corrections for accurate anisotropy measurements. In addition, the (selective) excitation (photoselection) and anisotropy of populations that interact with single or multiple intense polarised laser pulses is demonstrated as function of power density and beam profile. Using example values of real world experiments it is calculated to what extent this effectively orients the ensemble of particles. Finally, the implementation includes the interaction with multiple pulses in addition to depth averaging in optically dense samples. In summary, we show that mathematical modelling is essential to model and resolve the details of physical behaviour of populations in ultrafast spectroscopy such as pump-probe, pump-dump-probe and pump-repump-probe experiments.
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Affiliation(s)
- Luuk J. G. W. van Wilderen
- Division of Molecular Biosciences, Faculty of Natural Sciences, South Kensington Campus, Imperial College London, London, United Kingdom
| | - Craig N. Lincoln
- Division of Molecular Biosciences, Faculty of Natural Sciences, South Kensington Campus, Imperial College London, London, United Kingdom
| | - Jasper J. van Thor
- Division of Molecular Biosciences, Faculty of Natural Sciences, South Kensington Campus, Imperial College London, London, United Kingdom
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van Wilderen LJGW, Clark IP, Towrie M, van Thor JJ. Mid-infrared picosecond pump-dump-probe and pump-repump-probe experiments to resolve a ground-state intermediate in cyanobacterial phytochrome Cph1. J Phys Chem B 2010; 113:16354-64. [PMID: 19950906 DOI: 10.1021/jp9038539] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Multipulse picosecond mid-infrared spectroscopy has been used to study photochemical reactions of the cyanobacterial phytochrome photoreceptor Cph1. Different photophysical schemes have been discussed in the literature to describe the pathways after photoexcitation, particularly, to identify reaction phases that are linked to photoisomerisation and electronic decay in the 1566-1772 cm(-1) region that probes C=C and C=O stretching modes of the tetrapyrrole chromophore. Here, multipulse spectroscopy is employed, where, compared to conventional visible pump-mid-infrared probe spectroscopy, an additional visible pulse is incorporated that interacts with populations that are evolving on the excited- and ground-state potential energy surfaces. The time delays between the pump and the dump pulse are chosen such that the dump pulse interacts with different phases in the reaction process. The pump and dump pulses are at the same wavelength, 640 nm, and are resonant with the Pr ground state as well as with the excited state and intermediates. Because the dump pulse additionally pumps the remaining, partially recovered, and partially oriented ground-state population, theory is developed for estimating the fraction of excited-state molecules. The calculations take into account the model-dependent ground-state recovery fraction, the angular dependence of the population transfer resulting from the finite bleach that occurs with linearly polarized intense femtosecond optical excitation, and the partially oriented population for the dump field. Distinct differences between the results from the experiments that use a 1 or a 14 ps dump time favor a branching evolution from S1 to an excited state or reconfigured chromophore and to a newly identified ground-state intermediate (GSI). Optical dumping at 1 ps shows the instantaneous induced absorption of a delocalized C=C stretching mode at 1608 cm(-1), where the increased cross section is associated with the electronic ground-state structure of the ZZZ configuration of the linear tetrapyrrole chromophore. The dump-induced absorption decays with time constants of 5 and 19 ps to the Pr ground state. Employing a dump pulse at 14 ps results in an instantaneous decrease of the absorption of the 1608 cm(-1) band, indicating repumping of the GSI. The dump-induced absorption recovers back to the GSI with a 6 ps lifetime. A spectral similarity is observed between the 6 ps phase in the dump experiment and the 3 ps component found in the two-pulse pump-probe measurement. Combined with the dominance of ground-state absorption bands in the dump-induced spectrum, this indicates the presence of a GSI, which is additionally characterized by previously unidentified induced absorption at 1710 and 1570-80 cm(-1). The metastable photoproduct Lumi-R, which is in the electronic ground state and populated at 500 ps after excitation of Pr, is highly efficiently repumped into the Pr ground state with the power density used. After repumping, Lumi-R is not recovered on the 500 ps time scale of the experiment and is distinct from the GSI of Pr since it is not associated with its characteristic induced absorption at 1710 and 1570-80 cm(-1).
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Affiliation(s)
- Luuk J G W van Wilderen
- Division of Molecular Biosciences, Faculty of Natural Sciences, South Kensington Campus, Imperial College London, London SW7 2AZ, UK
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van Wilderen LJGW, Key JM, Van Stokkum IHM, van Grondelle R, Groot ML. Dynamics of Carbon Monoxide Photodissociation in Bradyrhizobium japonicum FixL Probed by Picosecond Midinfrared Spectroscopy. J Phys Chem B 2008; 113:3292-7. [DOI: 10.1021/jp8050565] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Affiliation(s)
- Luuk J. G. W. van Wilderen
- Department of Physics and Astronomy, Faculty of Sciences, Vrije Universiteit, De Boelelaan 1081, 1081 HV Amsterdam, The Netherlands and Laboratory for Microbiology, Swammerdam Institute for Life Sciences, University of Amsterdam, Nieuwe Achtergracht 166, 1018 WV Amsterdam, The Netherlands
| | - Jason M. Key
- Department of Physics and Astronomy, Faculty of Sciences, Vrije Universiteit, De Boelelaan 1081, 1081 HV Amsterdam, The Netherlands and Laboratory for Microbiology, Swammerdam Institute for Life Sciences, University of Amsterdam, Nieuwe Achtergracht 166, 1018 WV Amsterdam, The Netherlands
| | - Ivo H. M. Van Stokkum
- Department of Physics and Astronomy, Faculty of Sciences, Vrije Universiteit, De Boelelaan 1081, 1081 HV Amsterdam, The Netherlands and Laboratory for Microbiology, Swammerdam Institute for Life Sciences, University of Amsterdam, Nieuwe Achtergracht 166, 1018 WV Amsterdam, The Netherlands
| | - Rienk van Grondelle
- Department of Physics and Astronomy, Faculty of Sciences, Vrije Universiteit, De Boelelaan 1081, 1081 HV Amsterdam, The Netherlands and Laboratory for Microbiology, Swammerdam Institute for Life Sciences, University of Amsterdam, Nieuwe Achtergracht 166, 1018 WV Amsterdam, The Netherlands
| | - Marie Louise Groot
- Department of Physics and Astronomy, Faculty of Sciences, Vrije Universiteit, De Boelelaan 1081, 1081 HV Amsterdam, The Netherlands and Laboratory for Microbiology, Swammerdam Institute for Life Sciences, University of Amsterdam, Nieuwe Achtergracht 166, 1018 WV Amsterdam, The Netherlands
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Groot ML, van Wilderen LJGW, Di Donato M. Time-resolved methods in biophysics. 5. Femtosecond time-resolved and dispersed infrared spectroscopy on proteins. Photochem Photobiol Sci 2007; 6:501-7. [PMID: 17487299 DOI: 10.1039/b613023b] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Abstract
In this contribution we describe how femtosecond time-resolved infrared spectroscopy provides insight into the function and dynamics of pigment-protein complexes, and what the technical requirements are to perform such experiments. We further discuss a few examples of experiments performed on the photoactive yellow protein and photosynthetic complexes in more detail.
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Affiliation(s)
- Marie Louise Groot
- Department of Physics and Astronomy, Faculty of Sciences, Vrije Universiteit, De Boelelaan 1081, 1081 HV, Amsterdam, The Netherlands.
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Groot ML, Pawlowicz NP, van Wilderen LJGW, Breton J, van Stokkum IHM, van Grondelle R. Initial electron donor and acceptor in isolated Photosystem II reaction centers identified with femtosecond mid-IR spectroscopy. Proc Natl Acad Sci U S A 2005; 102:13087-92. [PMID: 16135567 PMCID: PMC1196200 DOI: 10.1073/pnas.0503483102] [Citation(s) in RCA: 176] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2005] [Indexed: 11/18/2022] Open
Abstract
Despite the apparent similarity between the plant Photosystem II reaction center (RC) and its purple bacterial counterpart, we show in this work that the mechanism of charge separation is very different for the two photosynthetic RCs. By using femtosecond visible-pump-mid-infrared probe spectroscopy in the region of the chlorophyll ester and keto modes, between 1,775 and 1,585 cm(-1), with 150-fs time resolution, we show that the reduction of pheophytin occurs on a 0.6- to 0.8-ps time scale, whereas P+, the precursor state for water oxidation, is formed after approximately 6 ps. We conclude therefore that in the Photosystem II RC the primary charge separation occurs between the "accessory chlorophyll" Chl(D1) and the pheophytin on the so-called active branch.
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Affiliation(s)
- Marie Louise Groot
- Faculty of Sciences, Vrije Universiteit, 1081 HV, Amsterdam, The Netherlands.
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Groot ML, Breton J, van Wilderen LJGW, Dekker JP, van Grondelle R. Femtosecond Visible/Visible and Visible/Mid-IR Pump−Probe Study of the Photosystem II Core Antenna Complex CP47. J Phys Chem B 2004. [DOI: 10.1021/jp037966s] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Marie Louise Groot
- Faculty of Sciences, Vrije Universiteit, 1081 HV Amsterdam, The Netherlands, and Service de Bioénergétique, Bât. 532, CEA-Saclay, 91191 Gif-sur-Yvette, France
| | - Jacques Breton
- Faculty of Sciences, Vrije Universiteit, 1081 HV Amsterdam, The Netherlands, and Service de Bioénergétique, Bât. 532, CEA-Saclay, 91191 Gif-sur-Yvette, France
| | - Luuk J. G. W. van Wilderen
- Faculty of Sciences, Vrije Universiteit, 1081 HV Amsterdam, The Netherlands, and Service de Bioénergétique, Bât. 532, CEA-Saclay, 91191 Gif-sur-Yvette, France
| | - Jan P. Dekker
- Faculty of Sciences, Vrije Universiteit, 1081 HV Amsterdam, The Netherlands, and Service de Bioénergétique, Bât. 532, CEA-Saclay, 91191 Gif-sur-Yvette, France
| | - Rienk van Grondelle
- Faculty of Sciences, Vrije Universiteit, 1081 HV Amsterdam, The Netherlands, and Service de Bioénergétique, Bât. 532, CEA-Saclay, 91191 Gif-sur-Yvette, France
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Groot ML, van Wilderen LJGW, Larsen DS, van der Horst MA, van Stokkum IHM, Hellingwerf KJ, van Grondelle R. Initial steps of signal generation in photoactive yellow protein revealed with femtosecond mid-infrared spectroscopy. Biochemistry 2003; 42:10054-9. [PMID: 12939133 DOI: 10.1021/bi034878p] [Citation(s) in RCA: 114] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Photoactive yellow protein (PYP) is a bacterial blue light sensor that induces Halorhodospira halophila to swim away from intense blue light. Light absorption by PYP's intrinsic chromophore, p-coumaric acid, leads to the initiation of a photocycle that comprises several distinct intermediates. Here we describe the initial structural changes of the chromophore and its nearby amino acids, using visible pump/mid-infrared probe spectroscopy. Upon photoexcitation, the trans bands of the chromophore are bleached, and shifts of the phenol ring bands occur. The latter are ascribed to charge translocation, which probably plays an essential role in driving the trans to cis isomerization process. We conclude that breaking of the hydrogen bond of the chromophore's C=O group with amino acid Cys69 and formation of a stable cis ground state occur in approximately 2 ps. Dynamic changes also include rearrangements of the hydrogen-bonding network of the amino acids around the chromophore. Relaxation of the coumaryl tail of the chromophore occurs in 0.9-1 ns, which event we identify with the I(0) to I(1) transition observed in visible spectroscopy.
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Affiliation(s)
- Marie Louise Groot
- Faculty of Sciences, Vrije Universiteit, 1081 HV Amsterdam, The Netherlands.
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