1
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Im J, Lee J, Lee JH. Surface Accessibility of an Intrinsically Disordered Protein Probed by 2D Time-Resolved Laser-Assisted NMR Spectroscopy. J Am Chem Soc 2022; 144:17010-17021. [PMID: 36083135 DOI: 10.1021/jacs.2c06309] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Probing the protein surface accessibility of different residues is a powerful way of characterizing the overall conformation of intrinsically disordered proteins (IDPs). We present a two-dimensional (2D) time-resolved photo-CIDNP (TR-CIDNP) experiment suitable for IDP analysis. Pulse stretching of high-power laser pulses, band-selective decoupling of 13Cα, and simultaneous application of radiofrequency and laser pulses were implemented to quantitatively analyze the IDP surface at ultrahigh resolution. Comparative analysis with other methods that measure protein surface accessibility validated the newly developed method and emphasized the importance of dye charge in photo-CIDNP. Using the neutral riboflavin dye, surface accessibilities were measured to be nearly identical for the four Tyr residues of α-synuclein (α-Syn), whose 1Hα-13Cα correlations were well-resolved in the 2D TR-CIDNP spectrum. Having confirmed the similarity between the time-resolved and steady-state photo-CIDNP results for α-Syn, we used the more sensitive latter method to show that divalent cations induce compaction of the C-terminal region and release of the N-terminal region of α-Syn. The photo-CIDNP method presented herein can be used as an orthogonal and independent method for investigating important biological processes associated with changes in the overall IDP conformation.
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Affiliation(s)
- Jonghyuk Im
- Department of Chemistry, Seoul National University, Seoul 08826, Korea
| | - Jongchan Lee
- Department of Chemistry, Seoul National University, Seoul 08826, Korea
| | - Jung Ho Lee
- Department of Chemistry, Seoul National University, Seoul 08826, Korea.,Advanced Institutes of Convergence Technology, Suwon, Gyeonggi-do 16229, Korea
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2
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Morozova OB, Stass DV, Yurkovskaya AV. Kinetic evidence for the transiently shifted acidity constant of histidine linked to paramagnetic tyrosine probed by intramolecular electron transfer in oxidized peptides. Phys Chem Chem Phys 2021; 23:16698-16706. [PMID: 34338250 DOI: 10.1039/d1cp02408f] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The kinetics of electron transfer (ET) from tyrosine (Tyr) to short-lived histidine (His) radicals in peptides of different structures was monitored using time-resolved chemically induced dynamic nuclear polarization (CIDNP) to follow the reduction of the His radicals using NMR detection of the diamagnetic hyperpolarized reaction products. In aqueous solution over a wide pH range, His radicals were generated in situ in the photo-induced reaction with the photosensitizer, 3,3',4,4'-tetracarboxy benzophenone. Model simulations of the CIDNP kinetics provided pH-dependent rate constants of intra- and intermolecular ET, and the pH dependencies of the reaction under study were interpreted in terms of protonation states of the reactants and the product, His with either protonated or neutral imidazole. In some cases, an increase of pKa of imidazole in the presence of the short-lived radical center at a nearby Tyr residue was revealed. Interpretation of the obtained pH dependencies made is possible to quantify the degree of paramagnetic shift of the acidity constant of the imidazole of the His residue in the peptides with a Tyr residue in its paramagnetic state, and to correlate this degree with the intramolecular ET rate constant - a higher intramolecular ET rate constant corresponded to a greater acidity constant shift.
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Affiliation(s)
- Olga B Morozova
- International Tomography Center, Institutskaya 3a, 630090 Novosibirsk, Russia.
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3
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Fare C, Yuan L, Cordon-Preciado V, Michels JJ, Bearpark MJ, Rich P, van Thor JJ. Radical-Triggered Reaction Mechanism of the Green-to-Red Photoconversion of EosFP. J Phys Chem B 2020; 124:7765-7778. [PMID: 32805110 DOI: 10.1021/acs.jpcb.0c04587] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Reaction intermediates in the green-to-red photoconversion of the photochromic fluorescent protein EosFP have been observed using high-intensity continuous blue illumination. An intermediate was identified through light-induced accumulation that continues to convert the green form in subsequent darkness, putatively containing a tyrosyl radical, albeit with anomalously shifted features in both the electronic and FTIR spectra. Lowering the pH to 5.5 significantly delays the decay of this tyrosyl intermediate, which is accompanied by Stark-shifted features in the electronic spectra of reactants and products. Vibrational mode assignments for the high-frequency and fingerprint FTIR spectral regions of the reaction intermediates support a proposed sequence of events where the newly formed Cα═Cβ ethylenic bond precedes modifications on the His-62 imidazole ring and confirms a C═O(NH2) product group on Phe-61. We propose a reaction mechanism that involves tyrosyl generation via singlet excited-state-mediated oxidation which subsequently triggers the covalent reactions by oxidation of the green chromophore.
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Affiliation(s)
- Clyde Fare
- Molecular Biophysics, Imperial College London, South Kensington Campus, London SW7 2AZ, United Kingdom.,Department of Chemistry, Molecular Sciences Research Hub, Imperial College London, White City Campus, 80 Wood Lane, London SW7 2AZ, United Kingdom
| | - Letong Yuan
- Molecular Biophysics, Imperial College London, South Kensington Campus, London SW7 2AZ, United Kingdom
| | - Violeta Cordon-Preciado
- Molecular Biophysics, Imperial College London, South Kensington Campus, London SW7 2AZ, United Kingdom
| | - Jasper J Michels
- Division of Molecular Electronics, Max Planck Institute for Polymer Research, Ackermannweg 10, 55128 Mainz, Germany
| | - Michael J Bearpark
- Department of Chemistry, Molecular Sciences Research Hub, Imperial College London, White City Campus, 80 Wood Lane, London SW7 2AZ, United Kingdom
| | - Peter Rich
- Department of Structural and Molecular Biology, University College London, Gower Street, London WC1E 6BT, United Kingdom
| | - Jasper J van Thor
- Molecular Biophysics, Imperial College London, South Kensington Campus, London SW7 2AZ, United Kingdom
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4
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Morozova OB. Reduction of Transient Histidine Radicals by Tyrosine: Influence of the Protonation State of Reactants. Chemphyschem 2020; 21:43-50. [PMID: 31709709 DOI: 10.1002/cphc.201901020] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2019] [Indexed: 11/07/2022]
Abstract
The role of tyrosine radicals as mediators of electron transfer reactions in enzymes is well established, as is the involvement of histidine as a binding partner. But how environmental factors affect these reactions remains poorly explored. In the study presented here, kinetic data on the influence of the protonation state of the reactants on the reduction of transient histidine radicals by tyrosine were obtained in neutral and basic aqueous solution (pH 6-12) using time-resolved chemically induced dynamic nuclear polarization (CIDNP). The histidine radicals were generated in the photo-induced reaction with the photosensitizer 3,3',4,4'-tetracarboxy benzophenone. From model simulations of the detected CIDNP kinetics, pH dependent second-order rate constants of the reduction of histidine radicals were obtained for four possible combinations of the amino acids and their N-acetyl derivatives, and also for the systems histidine-phenylalanine dipeptide/N-acetyl tyrosine, and N-acetyl histidine/tyrosine-glutamine dipeptide. The pH dependences of the rate constant of the reduction reaction are explained accounting for the protonation states of reactants, and also protonation state of the equilibrium form of the product - reduced form of histidine radical, which is histidine with neutral or a positively charged imidazole.
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Affiliation(s)
- Olga B Morozova
- International Tomography Center, Institutskaya 3a, 630090, Novosibirsk, Russia.,Novosibirsk State University, Pirogova 2, 630090, Novosibirsk, Russia
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5
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Morozova OB, Sherin PS, Yurkovskaya AV. Competition of singlet and triplet recombination of radical pairs in photoreactions of carboxy benzophenones and aromatic amino acids. Phys Chem Chem Phys 2019; 21:2017-2028. [PMID: 30633277 DOI: 10.1039/c8cp06760k] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Time-resolved chemically induced dynamic nuclear polarization (CIDNP) and transient absorption (TA) were applied to reveal the branching ratio of the singlet and triplet recombination channels in the reaction of short-lived radicals of carboxy benzophenones and the aromatic amino acids histidine, tryptophan, and tyrosine in neutral aqueous solution. It was established that the share of triplet recombination increases with increasing number of carboxylic groups: no triplet recombination was found for 4-carboxy benzophenone, whereas ∼13% of radicals of 4,4'-dicarboxy benzophenone (DCBP) and ∼27% of radicals of 3,3',4,4'-tetracarboxy benzophenone (TCBP) react with histidine radicals from the triplet state of radical pairs. The main idea is that the protonated (π,π*) triplet state of TCBP or DCBP is populated via back electron transfer from the ketyl radical of TCBP or DCBP to the radical of the amino acid. The protonated triplet state of the ketone decays with the formation of a metastable hydroxylated product, which is detected by TA. Taking into account triplet recombination provides excellent coincidence between experimental data and the simulated CIDNP kinetics.
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Affiliation(s)
- Olga B Morozova
- International Tomography Center, Institutskaya 3a, 630090 Novosibirsk, Russia.
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6
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Morozova OB, Ivanov KL. Time-Resolved Chemically Induced Dynamic Nuclear Polarization of Biologically Important Molecules. Chemphyschem 2018; 20:197-215. [DOI: 10.1002/cphc.201800566] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2018] [Revised: 10/11/2018] [Indexed: 11/11/2022]
Affiliation(s)
- Olga B. Morozova
- International Tomography Center; Institutskaya 3a 630090 Novosibirsk Russia
- Novosibirsk State University; Pirogova 2 630090 Novosibirsk Russia
| | - Konstantin L. Ivanov
- International Tomography Center; Institutskaya 3a 630090 Novosibirsk Russia
- Novosibirsk State University; Pirogova 2 630090 Novosibirsk Russia
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7
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Ing NL, El-Naggar MY, Hochbaum AI. Going the Distance: Long-Range Conductivity in Protein and Peptide Bioelectronic Materials. J Phys Chem B 2018; 122:10403-10423. [DOI: 10.1021/acs.jpcb.8b07431] [Citation(s) in RCA: 83] [Impact Index Per Article: 13.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
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8
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Morozova OB, Fishman NN, Yurkovskaya AV. Kinetics of Reversible Protonation of Transient Neutral Guanine Radical in Neutral Aqueous Solution. Chemphyschem 2018; 19:2696-2702. [PMID: 29978943 DOI: 10.1002/cphc.201800539] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2018] [Indexed: 11/11/2022]
Abstract
Time-resolved chemically induced dynamic nuclear polarization (TR-CIDNP) is applied to follow transformation of the short-lived neutral guanine radical into a secondary guanine radical by its protonation, presumably at position N7. In the initial step the photoreaction of guanosine-5'-monophosphate (GMP) with triplet excited 3,3',4,4'-tetracarboxy benzophenone (TCBP) leads to formation of the neutral radical G(-H). . The evidence of the radical conversion is based on the inversion of CIDNP sign for TCBP and GMP protons on the microsecond timescale as a result of the change in magnetic resonance parameters in the pairs of TCBP and GMP radicals due to structural changes of the GMP radical. Acceleration of the CIDNP sign change upon addition of phosphate (proton donor) confirms that the radical transformation responsible for the observed CIDNP kinetics is protonation of the neutral guanine radical with formation of the newly characterized cation radical, (G.+ )'. From the full analysis of the pH-dependent CIDNP kinetics, the protonation and deprotonation behaviour is quantitatively characterized, giving pKa =8.0±0.2 of the cation radical (G.+ )'.
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Affiliation(s)
- Olga B Morozova
- International Tomography Center, Institutskaya 3a, 630090, Novosibirsk, Russia.,Novosibirsk State University, Pirogova 2, 630090, Novosibirsk, Russia
| | - Natalya N Fishman
- International Tomography Center, Institutskaya 3a, 630090, Novosibirsk, Russia.,Novosibirsk State University, Pirogova 2, 630090, Novosibirsk, Russia
| | - Alexandra V Yurkovskaya
- International Tomography Center, Institutskaya 3a, 630090, Novosibirsk, Russia.,Novosibirsk State University, Pirogova 2, 630090, Novosibirsk, Russia
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9
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Morozova OB, Panov MS, Fishman NN, Yurkovskaya AV. Electron transfer vs. proton-coupled electron transfer as the mechanism of reaction between amino acids and triplet-excited benzophenones revealed by time-resolved CIDNP. Phys Chem Chem Phys 2018; 20:21127-21135. [DOI: 10.1039/c8cp03591a] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
We use proportionality between NMR signal enhancements in geminate products and hyperfine coupling constants in transient radicals to elucidate reaction mechanism in detail.
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Affiliation(s)
- Olga B. Morozova
- International Tomography Center
- 630090 Novosibirsk
- Russia
- Novosibirsk State University
- 630090 Novosibirsk
| | - Mikhail S. Panov
- International Tomography Center
- 630090 Novosibirsk
- Russia
- Novosibirsk State University
- 630090 Novosibirsk
| | - Natalya N. Fishman
- International Tomography Center
- 630090 Novosibirsk
- Russia
- Novosibirsk State University
- 630090 Novosibirsk
| | - Alexandra V. Yurkovskaya
- International Tomography Center
- 630090 Novosibirsk
- Russia
- Novosibirsk State University
- 630090 Novosibirsk
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10
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Agarwal R, Chauvet AAP. Ultrafast dynamics of the photo-excited hemes b and c n in the cytochrome b 6f complex. Phys Chem Chem Phys 2017; 19:3287-3296. [PMID: 28085168 DOI: 10.1039/c6cp08077d] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The dynamics of hemes b and cn within the cytochrome b6f complex are investigated by means of ultrafast broad-band transient absorption spectroscopy. On the one hand, the data reveal that, subsequent to visible light excitation, part of the b hemes undergoes pulse-limited photo-oxidation, with the liberated electron supposedly being transferred to one of the adjacent aromatic amino acids. Photo-oxidation is followed by charge recombination in about 8.2 ps. Subsequent to charge recombination, heme b is promoted to a vibrationally excited ground state that relaxes in about 4.6 ps. On the other hand, heme cn undergoes ultrafast ground state recovery in about 140 fs. Interestingly, the data also show that, in contrast to previous beliefs, Chl a is involved in the photochemistry of hemes. Indeed, subsequent to heme excitation, Chl a bleaches and recovers to its ground state in 90 fs and 650 fs, respectively. Chl a bleaching allegedly corresponds to the formation of a short lived Chl a anion. Beyond the previously suggested structural role, this study provides unique evidence that Chl a is directly involved in the photochemistry of the hemes.
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Affiliation(s)
- Rachna Agarwal
- Department of Biological Sciences, Purdue University, West Lafayette, Indiana 47907, USA and Molecular Biology Division, Bhabha Atomic Research Centre, Mumbai 400 085, India
| | - Adrien A P Chauvet
- Ecole Polytechnique Fédérale de Lausanne (EPFL), Laboratoire de Spectroscopie Ultrarapide (LSU), ISIC, Faculté des Sciences de Base and Lausanne Centre for Ultrafast Science (LACUS), Station 6, 1015 Lausanne, Switzerland. and The University of Sheffield, Department of Chemistry, Dainton Building, Brook Hill, Sheffield S3 7HF, UK
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11
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Houée-Lévin C, Bobrowski K, Horakova L, Karademir B, Schöneich C, Davies MJ, Spickett CM. Exploring oxidative modifications of tyrosine: An update on mechanisms of formation, advances in analysis and biological consequences. Free Radic Res 2015; 49:347-73. [DOI: 10.3109/10715762.2015.1007968] [Citation(s) in RCA: 80] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
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12
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Chauvet AAP, Al Haddad A, Kao WC, van Mourik F, Hunte C, Chergui M. Photo-induced dynamics of the heme centers in cytochrome bc1. Phys Chem Chem Phys 2015; 17:2143-51. [DOI: 10.1039/c4cp04805a] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
The ultrafast response of cytochromebc1is investigated for the first time,viatransient absorption spectroscopy.
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Affiliation(s)
- Adrien A. P. Chauvet
- Ecole Polytechnique Fédérale de Lausanne (EPFL)
- Laboratoire de Spectroscopie Ultrarapide
- ISIC
- 1015 Lausanne
- Switzerland
| | - André Al Haddad
- Ecole Polytechnique Fédérale de Lausanne (EPFL)
- Laboratoire de Spectroscopie Ultrarapide
- ISIC
- 1015 Lausanne
- Switzerland
| | - Wei-Chun Kao
- Albert-Ludwigs-Universität Freiburg
- BIOSS Centre for Biological Signalling Studies
- Institute for Biochemistry and Biology
- 79104 Freiburg
- Germany
| | - Frank van Mourik
- Ecole Polytechnique Fédérale de Lausanne (EPFL)
- Laboratoire de Spectroscopie Ultrarapide
- ISIC
- 1015 Lausanne
- Switzerland
| | - Carola Hunte
- Albert-Ludwigs-Universität Freiburg
- BIOSS Centre for Biological Signalling Studies
- Institute for Biochemistry and Biology
- 79104 Freiburg
- Germany
| | - Majed Chergui
- Ecole Polytechnique Fédérale de Lausanne (EPFL)
- Laboratoire de Spectroscopie Ultrarapide
- ISIC
- 1015 Lausanne
- Switzerland
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13
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Saprygina NN, Morozova OB, Grampp G, Yurkovskaya AV. Effect of Amino Group Charge on the Photooxidation Kinetics of Aromatic Amino Acids. J Phys Chem A 2013; 118:339-49. [DOI: 10.1021/jp4097919] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Natalya N. Saprygina
- International Tomography Center, Institutskaya
3a, 630090 Novosibirsk, Russia
- Novosibirsk State University, Pirogova 2, 630090 Novosibirsk, Russia
| | - Olga B. Morozova
- International Tomography Center, Institutskaya
3a, 630090 Novosibirsk, Russia
- Novosibirsk State University, Pirogova 2, 630090 Novosibirsk, Russia
| | - Günter Grampp
- Institute
of Physical and Theoretical Chemistry, Graz University of Technology, Stremayrgasse
9, 8010 Graz, Austria
| | - Alexandra V. Yurkovskaya
- International Tomography Center, Institutskaya
3a, 630090 Novosibirsk, Russia
- Novosibirsk State University, Pirogova 2, 630090 Novosibirsk, Russia
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14
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Abramova TV, Morozova OB, Silnikov VN, Yurkovskaya AV. Synthesis of nucleotide-amino acid conjugates designed for photo-CIDNP experiments by a phosphotriester approach. Beilstein J Org Chem 2013; 9:2898-909. [PMID: 24367455 PMCID: PMC3869286 DOI: 10.3762/bjoc.9.326] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2013] [Accepted: 11/15/2013] [Indexed: 11/23/2022] Open
Abstract
Conjugates of 2’-deoxyguanosine, L-tryptophan and benzophenone designed to study pathways of fast radical reactions by the photo Chemically Induced Dynamic Nuclear Polarization (photo-CIDNP) method were obtained by the phosphotriester block liquid phase synthesis. The phosphotriester approach to the oligonucleotide synthesis was shown to be a versatile and economic strategy for preparing the required amount of high quality samples of nucleotide–amino acid conjugates.
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Affiliation(s)
- Tatyana V Abramova
- Institute of Chemical Biology and Fundamental Medicine, SB RAS, Lavrent'ev Ave, 8, Novosibirsk 630090, Russia ; Novosibirsk State University, Pirogova St. 2, Novosibirsk 630090, Russia
| | - Olga B Morozova
- Novosibirsk State University, Pirogova St. 2, Novosibirsk 630090, Russia ; International Tomography Center, SB RAS, Institutskaya 3a, Novosibirsk 630090, Russia
| | - Vladimir N Silnikov
- Institute of Chemical Biology and Fundamental Medicine, SB RAS, Lavrent'ev Ave, 8, Novosibirsk 630090, Russia
| | - Alexandra V Yurkovskaya
- Novosibirsk State University, Pirogova St. 2, Novosibirsk 630090, Russia ; International Tomography Center, SB RAS, Institutskaya 3a, Novosibirsk 630090, Russia
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15
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Abstract
Photo-chemically induced dynamic nuclear polarization (CIDNP) is a nuclear magnetic resonance (NMR) phenomenon which, among other things, is exploited to extract information on biomolecular structure via probing solvent-accessibilities of tryptophan (Trp), tyrosine (Tyr), and histidine (His) amino acid side chains both in polypeptides and proteins in solution. The effect, normally triggered by a (laser) light-induced photochemical reaction in situ, yields both positive and/or negative signal enhancements in the resulting NMR spectra which reflect the solvent exposure of these residues both in equilibrium and during structural transformations in "real time". As such, the method can offer - qualitatively and, to a certain extent, quantitatively - residue-specific structural and kinetic information on both the native and, in particular, the non-native states of proteins which, often, is not readily available from more routine NMR techniques. In this review, basic experimental procedures of the photo-CIDNP technique as applied to amino acids and proteins are discussed, recent improvements to the method highlighted, and future perspectives presented. First, the basic principles of the phenomenon based on the theory of the radical pair mechanism (RPM) are outlined. Second, a description of standard photo-CIDNP applications is given and it is shown how the effect can be exploited to extract residue-specific structural information on the conformational space sampled by unfolded or partially folded proteins on their "path" to the natively folded form. Last, recent methodological advances in the field are highlighted, modern applications of photo-CIDNP in the context of biological NMR evaluated, and an outlook into future perspectives of the method is given.
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Affiliation(s)
- Lars T Kuhn
- DFG Research Center Molecular Physiology of the Brain (CMPB), European Neuroscience Institute Göttingen (ENI-G) and EXC 171 Microscopy at the Nanometer Range, Göttingen, Germany,
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16
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Kiryutin AS, Korchak SE, Ivanov KL, Yurkovskaya AV, Vieth HM. Creating Long-Lived Spin States at Variable Magnetic Field by Means of Photochemically Induced Dynamic Nuclear Polarization. J Phys Chem Lett 2012; 3:1814-1819. [PMID: 26291865 DOI: 10.1021/jz3005046] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
We have shown that long-lived spin states (LLS) can be selectively populated by photogenerated chemically induced dynamic nuclear polarization (CIDNP) over a wide range of magnetic fields. Relaxation times of LLS of the β-CH2 protons in N-acetyl histidine and partially deuterated histidine have been measured. Our experiments demonstrate that CIDNP enables creating LLS in the amino acid in a field range of up to a few Tesla and that their lifetimes can be 45 times longer than T1. The advantage of the method is thus two-fold: it allows one to accumulate high levels of spin hyperpolarization and to preserve them for periods of time far exceeding T1. Therefore, photo-CIDNP is a technique suitable for creating long-lived spin order in biologically relevant molecules.
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Affiliation(s)
- Alexey S Kiryutin
- †Institute of Experimental Physics, Freie Universität Berlin, Arnimallee14, D-14195 Berlin, Germany
- ‡International Tomography Center, Institutskaya 3a, 630090, Novosibirsk, Russia
| | - Sergey E Korchak
- †Institute of Experimental Physics, Freie Universität Berlin, Arnimallee14, D-14195 Berlin, Germany
- §Physikalisch-Technische Bundesanstalt, Abbestr. 2-12, D-10587 Berlin, Germany
| | - Konstantin L Ivanov
- ‡International Tomography Center, Institutskaya 3a, 630090, Novosibirsk, Russia
- ∥Novosibirsk State University, Pirogova 2, 630090, Novosibirsk, Russia
| | - Alexandra V Yurkovskaya
- ‡International Tomography Center, Institutskaya 3a, 630090, Novosibirsk, Russia
- ∥Novosibirsk State University, Pirogova 2, 630090, Novosibirsk, Russia
| | - Hans-Martin Vieth
- †Institute of Experimental Physics, Freie Universität Berlin, Arnimallee14, D-14195 Berlin, Germany
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17
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Bonin J, Robert M. Photoinduced Proton-Coupled Electron Transfers in Biorelevant Phenolic Systems. Photochem Photobiol 2011; 87:1190-203. [DOI: 10.1111/j.1751-1097.2011.00996.x] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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18
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Li X, Chung LW, Mizuno H, Miyawaki A, Morokuma K. Competitive Mechanistic Pathways for Green-to-Red Photoconversion in the Fluorescent Protein Kaede: A Computational Study. J Phys Chem B 2010; 114:16666-75. [DOI: 10.1021/jp1101779] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Affiliation(s)
- Xin Li
- Fukui Institute for Fundamental Chemistry, Kyoto University, Kyoto 606-8103, Japan, and Laboratory for Cell Function and Dynamics, Advanced Technology Development Group, Brain Science Institute, RIKEN, 2-1 Hirosawa, Wako-city, Saitama, 351-0198, Japan
| | - Lung Wa Chung
- Fukui Institute for Fundamental Chemistry, Kyoto University, Kyoto 606-8103, Japan, and Laboratory for Cell Function and Dynamics, Advanced Technology Development Group, Brain Science Institute, RIKEN, 2-1 Hirosawa, Wako-city, Saitama, 351-0198, Japan
| | - Hideaki Mizuno
- Fukui Institute for Fundamental Chemistry, Kyoto University, Kyoto 606-8103, Japan, and Laboratory for Cell Function and Dynamics, Advanced Technology Development Group, Brain Science Institute, RIKEN, 2-1 Hirosawa, Wako-city, Saitama, 351-0198, Japan
| | - Atsushi Miyawaki
- Fukui Institute for Fundamental Chemistry, Kyoto University, Kyoto 606-8103, Japan, and Laboratory for Cell Function and Dynamics, Advanced Technology Development Group, Brain Science Institute, RIKEN, 2-1 Hirosawa, Wako-city, Saitama, 351-0198, Japan
| | - Keiji Morokuma
- Fukui Institute for Fundamental Chemistry, Kyoto University, Kyoto 606-8103, Japan, and Laboratory for Cell Function and Dynamics, Advanced Technology Development Group, Brain Science Institute, RIKEN, 2-1 Hirosawa, Wako-city, Saitama, 351-0198, Japan
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