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Zima V, Gladwish O, Marek A, Tureček F. Nucleoside Cation Radicals: Generation, Radical-Induced Hydrogen Atom Migrations, and Ribose Ring Cleavage in the Gas Phase. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2024; 35:1594-1608. [PMID: 38842116 DOI: 10.1021/jasms.4c00198] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2024]
Abstract
Nucleoside ions that were furnished on ribose with a 2'-O-acetyl radical group were generated in the gas phase by multistep collision-induced dissociation of precursor ions tagged with radical initiator groups, and their chemistry was investigated in the gas phase. 2'-O-Acetyladenosine cation radicals were found to undergo hydrogen transfer to the acetoxyl radical from the ribose ring positions that were elucidated using specific deuterium labeling of 1'-H, 2'-H, and 4'-H and in the N-H and O-H exchangeable positions, favoring 4'-H transfer. Ion structures and transition-state energies were calculated by a combination of Born-Oppenheimer molecular dynamics and density functional theory and used to obtain unimolecular rate constants for competitive hydrogen transfer and loss of the acetoxyl radical. Migrations to the acetoxyl radical of ribose hydrogens 1'-H, 2'-H, 3'-H, and 4'-H were all exothermic, but product formation was kinetically controlled. Both Rice-Ramsperger-Kassel-Marcus (RRKM) and transition-state theory (TST) calculations indicated preferential migration of 4'-H in a qualitative agreement with the deuterium labeling results. The hydrogen migrations displayed substantial isotope effects that along with quantum tunneling affected the relative rate constants and reaction branching ratios. UV-vis action spectroscopy indicated that the cation radicals from 2'-O-acetyladenosine consisted of a mixture of isomers. Radical-driven dissociations were also observed for protonated guanosine, cytosine, and thymidine conjugates. However, for those nucleoside ions and cation radicals, the dissociations were dominated by the loss of the nucleobase or formation of protonated nucleobase ions.
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Affiliation(s)
- Václav Zima
- Department of Chemistry, University of Washington, 351700 Bagley Hall, Seattle, Washington 98195-1700, United States
- Institute of Organic Chemistry and Biochemistry, Czech Academy of Sciences, 166 10 Prague, Czech Republic
| | - Owen Gladwish
- Department of Chemistry, Case Western Reserve University, Cleveland, Ohio 44106-7078, United States
| | - Aleš Marek
- Institute of Organic Chemistry and Biochemistry, Czech Academy of Sciences, 166 10 Prague, Czech Republic
| | - František Tureček
- Department of Chemistry, University of Washington, 351700 Bagley Hall, Seattle, Washington 98195-1700, United States
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2
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Gutiérrez-Quintanilla A, Moge B, Compagnon I, Noble JA. Vibrational and electronic spectra of protonated vanillin: exploring protonation sites and isomerisation. Phys Chem Chem Phys 2024; 26:15358-15368. [PMID: 38767194 DOI: 10.1039/d3cp05573f] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/22/2024]
Abstract
Photofragmentation spectra of protonated vanillin produced under electrospray ionisation (ESI) conditions have been recorded in the 3000-3700 cm-1 (vibrational) and 225-460 nm (electronic) ranges, using room temperature IRMPD (infrared multiphoton dissociation) and cryogenic UVPD (ultraviolet photodissociation) spectroscopies, respectively. The cold (∼50 K) electronic UVPD spectrum exhibits very well resolved vibrational structure for the S1 ← S0 and S3 ← S0 transitions, suggesting long excited state dynamics, similar to its simplest analogue, protonated benzaldehyde. The experimental data were combined with theoretical calculations to determine the protonation site and configurational isomer observed in the experiments.
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Affiliation(s)
- Alejandro Gutiérrez-Quintanilla
- CNRS, Aix Marseille Univ., PIIM, Physique des Interactions Ioniques et Moléculaires, UMR 7345, 13397 Marseille, France.
- Université de Pau et des Pays de l'Adour, E2S UPPA, CNRS, IPREM, Pau, France
| | - Baptiste Moge
- Univ. Lyon, Université Claude Bernard Lyon 1, CNRS, Institut Lumière Matière, F-69622 Villeurbanne, France
| | - Isabelle Compagnon
- Univ. Lyon, Université Claude Bernard Lyon 1, CNRS, Institut Lumière Matière, F-69622 Villeurbanne, France
| | - Jennifer A Noble
- CNRS, Aix Marseille Univ., PIIM, Physique des Interactions Ioniques et Moléculaires, UMR 7345, 13397 Marseille, France.
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3
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Parker K, Bollis NE, Ryzhov V. Ion-molecule reactions of mass-selected ions. MASS SPECTROMETRY REVIEWS 2024; 43:47-89. [PMID: 36447431 DOI: 10.1002/mas.21819] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/16/2023]
Abstract
Gas-phase reactions of mass-selected ions with neutrals covers a very broad area of fundamental and applied mass spectrometry (MS). Oftentimes, ion-molecule reactions (IMR) can serve as a viable alternative to collision-induced dissociation and other ion dissociation techniques when using tandem MS. This review focuses on the literature pertaining applications of IMR since 2013. During the past decade considerable efforts have been made in analytical applications of IMR, including advances in one of the major techniques for characterization of unsaturated fatty acids and lipids, ozone-induced dissociation, and the development of a new technique for sequencing of large ions, hydrogen atom attachment/abstraction dissociation. Many advances have also been made in identifying gas-phase chemistry specific to a functional group in organic and biological compounds, which are useful in structure elucidation of analytes and differentiation of isomers/isobars. With "soft" ionization techniques like electrospray ionization having become mainstream for quite some time now, the efforts in the area of metal ion catalysis have firmly moved into exploring chemistry of ligated metal complexes in their "natural" oxidation states allowing to model individual steps of mechanisms in homogeneous catalysis, especially in combination with high-level DFT calculations. Finally, IMR continue to contribute to the body of knowledge in the area of chemistry of interstellar processes.
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Affiliation(s)
- Kevin Parker
- Department of Chemistry and Biochemistry, Northern Illinois University, DeKalb, Illinois, USA
| | - Nicholas E Bollis
- Department of Chemistry and Biochemistry, Northern Illinois University, DeKalb, Illinois, USA
| | - Victor Ryzhov
- Department of Chemistry and Biochemistry, Northern Illinois University, DeKalb, Illinois, USA
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Raczyńska ED. On Prototropy and Bond Length Alternation in Neutral and Ionized Pyrimidine Bases and Their Model Azines in Vacuo. Molecules 2023; 28:7282. [PMID: 37959699 PMCID: PMC10648772 DOI: 10.3390/molecules28217282] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2023] [Revised: 10/21/2023] [Accepted: 10/22/2023] [Indexed: 11/15/2023] Open
Abstract
In this review, the complete tautomeric equilibria are derived for disubstituted pyrimidine nucleic acid bases starting from phenol, aniline, and their model compounds-monosubstituted aromatic azines. The differences in tautomeric preferences for isolated (gaseous) neutral pyrimidine bases and their model compounds are discussed in light of different functional groups, their positions within the six-membered ring, electronic effects, and intramolecular interactions. For the discussion of tautomeric preferences and for the analysis of internal effects, recent quantum-chemical results are taken into account and compared to some experimental ones. For each possible tautomer-rotamer of the title compounds, the bond length alternation, measured by means of the harmonic oscillator model of electron delocalization (HOMED) index, is examined. Significant HOMED similarities exist for mono- and disubstituted derivatives. The lack of parallelism between the geometric (HOMED) and energetic (ΔG) parameters for all possible isomers clearly shows that aromaticity is not the main factor that dictates tautomeric preferences for pyrimidine bases, particularly for uracil and thymine. The effects of one-electron loss (positive ionization) and one-electron gain (negative ionization) on prototropy and bond length alternation are also reviewed for pyrimidine bases and their models.
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Affiliation(s)
- Ewa Daniela Raczyńska
- Department of Chemistry, Warsaw University of Life Sciences (SGGW), ul. Nowoursynowska 159c, 02-776 Warszawa, Poland
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5
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Kou M, Jiao L, Xu S, Du M, Hou Y, Kong X. Structural Characterization of the Metalized Radical Cations of Adenosine ([Ade+Li-H] •+ and [Ade+Na-H] •+) by Infrared Multiphoton Dissociation Spectroscopy and Theoretical Studies. Int J Mol Sci 2023; 24:15385. [PMID: 37895065 PMCID: PMC10607295 DOI: 10.3390/ijms242015385] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2023] [Revised: 10/17/2023] [Accepted: 10/18/2023] [Indexed: 10/29/2023] Open
Abstract
Nucleoside radicals are key intermediates in the process of DNA damage, and alkali metal ions are a common group of ions in living organisms. However, so far, there has been a significant lack of research on the structural effects of alkali metal ions on nucleoside free radicals. In this study, we report a new method for generating metalized nucleoside radical cations in the gas phase. The radical cations [Ade+M-H]•+ (M = Li, Na) are generated by the 280 nm ultraviolet photodissociation (UVPD) of the precursor ions of lithiated and sodiated ions of 2-iodoadenine in a Fourier transform ion cyclotron resonance (FT ICR) cell. Further infrared multiphoton dissociation (IRMPD) spectra of both radical cations were recorded in the region of 2750-3750 cm-1. By combining these results with theoretical calculations, the most stable isomers of both radicals can be identified, which share the common characteristics of triple coordination patterns of the metal ions. For both radical species, the lowest-energy isomers undergo hydrogen transfer. Although the sugar ring in the most stable isomer of [Ade+Li-H]•+ is in a (South, syn) conformation similar to that of [Ado+Na]+, [Ade+Na-H]•+ is distinguished by the unexpected opening of the sugar ring. Their theoretical spectra are in good agreement with experimental spectra. However, due to the flexibility of the structures and the complexity of their potential energy surfaces, the hydrogen transfer pathways still need to be further studied. Considering that the free radicals formed directly after C-I cleavage have some similar spectral characteristics, the existence of these corresponding isomers cannot be ruled out. The findings imply that the structures of nucleoside radicals may be significantly influenced by the attached alkali metal ions. More detailed experiments and theoretical calculations are still crucial.
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Affiliation(s)
- Min Kou
- State Key Laboratory of Elemento-Organic Chemistry, Frontiers Science Center for New Organic Matter, College of Chemistry, Nankai University, Tianjin 300071, China
| | - Luyang Jiao
- State Key Laboratory of Elemento-Organic Chemistry, Frontiers Science Center for New Organic Matter, College of Chemistry, Nankai University, Tianjin 300071, China
| | - Shiyin Xu
- State Key Laboratory of Elemento-Organic Chemistry, Frontiers Science Center for New Organic Matter, College of Chemistry, Nankai University, Tianjin 300071, China
| | - Mengying Du
- State Key Laboratory of Elemento-Organic Chemistry, Frontiers Science Center for New Organic Matter, College of Chemistry, Nankai University, Tianjin 300071, China
| | - Yameng Hou
- State Key Laboratory of Elemento-Organic Chemistry, Frontiers Science Center for New Organic Matter, College of Chemistry, Nankai University, Tianjin 300071, China
| | - Xianglei Kong
- State Key Laboratory of Elemento-Organic Chemistry, Frontiers Science Center for New Organic Matter, College of Chemistry, Nankai University, Tianjin 300071, China
- Tianjin Key Laboratory of Biosensing and Molecular Recognition, College of Chemistry, Nankai University, Tianjin 300071, China
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Zima V, Vlk M, Wan J, Cvačka J, Tureček F. Tracking Isomerizations of High-Energy Adenine Cation Radicals by UV-Vis Action Spectroscopy and Cyclic Ion Mobility Mass Spectrometry. J Phys Chem A 2023. [PMID: 37433135 DOI: 10.1021/acs.jpca.3c03179] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/13/2023]
Abstract
We report experimental and computational studies of protonated adenine C-8 σ-radicals that are presumed yet elusive reactive intermediates of oxidative damage to nucleic acids. The radicals were generated in the gas phase by the collision-induced dissociation of C-8-Br and C-8-I bonds in protonated 8-bromo- and 8-iodoadenine as well as by 8-bromo- and 8-iodo-9-methyladenine. Protonation by electrospray of 8-bromo- and 8-iodoadenine was shown by cyclic-ion mobility mass spectrometry (c-IMS) to form the N-1-H, N-9-H and N-3-H, N-7-H protomers in 85:15 and 81:19 ratios, respectively, in accordance with the equilibrium populations of these protomers in water-solvated ions that were calculated by density functional theory (DFT). Protonation of 8-halogenated 9-methyladenines yielded single N-1-H protomers, which was consistent with their thermodynamic stability. The radicals produced from the 8-bromo and 8-iodo adenine cations were characterized by UV-vis photodissociation action spectroscopy (UVPD) and c-IMS. UVPD revealed the formation of C-8 σ-radicals along with N-3-H, N-7-H-adenine π-radicals that arose as secondary products by hydrogen atom migrations. The isomers were identified by matching their action spectra against the calculated vibronic absorption spectra. Deuterium isotope effects were found to slow the isomerization and increase the population of C-8 σ-radicals. The adenine cation radicals were separated by c-IMS and identified by their collision cross sections, which were measured relative to the canonical N-9-H adenine cation radical that was cogenerated in situ as an internal standard. Ab initio CCSD(T)/CBS calculations of isomer energies showed that the adenine C-8 σ-radicals were local energy minima with relative energies at 76-79 kJ mol-1 above that of the canonical adenine cation radical. Rice-Ramsperger-Kassel-Marcus calculations of unimolecular rate constants for hydrogen and deuterium migrations resulting in exergonic isomerizations showed kinetic shifts of 10-17 kJ mol-1, stabilizing the C-8 σ-radicals. C-8 σ-radicals derived from N-1-protonated 9-methyladenine were also thermodynamically unstable and readily isomerized upon formation.
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Affiliation(s)
- Václav Zima
- Department of Chemistry, University of Washington, Seattle, Washington 98195-1700, United States
| | - Mikuláš Vlk
- Institute of Organic Chemistry and Biochemistry, Czech Academy of Sciences, 16610 Prague 6, Czech Republic
- Department of Analytical Chemistry, Faculty of Science, Charles University, 12800 Prague, Czech Republic
| | - Jiahao Wan
- Department of Chemistry, University of Washington, Seattle, Washington 98195-1700, United States
| | - Josef Cvačka
- Institute of Organic Chemistry and Biochemistry, Czech Academy of Sciences, 16610 Prague 6, Czech Republic
- Department of Analytical Chemistry, Faculty of Science, Charles University, 12800 Prague, Czech Republic
| | - František Tureček
- Department of Chemistry, University of Washington, Seattle, Washington 98195-1700, United States
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7
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Tureček F. UV-vis spectroscopy of gas-phase ions. MASS SPECTROMETRY REVIEWS 2023; 42:206-226. [PMID: 34392556 DOI: 10.1002/mas.21726] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/11/2021] [Revised: 06/07/2021] [Accepted: 06/08/2021] [Indexed: 06/13/2023]
Abstract
Photodissociation action spectroscopy has made a great progress in expanding investigations of gas-phase ion structures. This review deals with aspects of gas-phase ion electronic excitations that result in wavelength-dependent dissociation and light emission via fluorescence, chiefly covering the ultraviolet and visible regions of the spectrum. The principles are briefly outlined and a few examples of instrumentation are presented. The main thrust of the review is to collect and selectively present applications of UV-vis action spectroscopy to studies of stable gas-phase ion structures and combinations of spectroscopy with ion mobility, collision-induced dissociation, and ion-ion reactions leading to the generation of reactive intermediates and electronic energy transfer.
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Affiliation(s)
- František Tureček
- Department of Chemistry, University of Washington, Seattle, Washington, USA
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8
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Molina F, Dezalay J, Soorkia S, Broquier M, Hochlaf M, Pino GA, Grégoire G. Cryogenic IR and UV spectroscopy of isomer-selected cytosine radical cation. Phys Chem Chem Phys 2022; 24:25182-25190. [DOI: 10.1039/d2cp03953b] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/12/2023]
Abstract
The UV photodissociation of cryogenic-cooled isomer-selected cytosine–silver complex leads to the production of cytosine radical cation without isomerization.
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Affiliation(s)
- Franco Molina
- Université Paris-Saclay, CNRS, Institut des Sciences Moléculaires d’Orsay, F-91405 Orsay, France
- INFIQC (CONICET-UNC), Ciudad Universitaria, Pabellón Argentina, 5000 Córdoba, Argentina
- Departamento de Fisicoquímica, Fac. de Ciencias Químicas, Universidad Nacional de Córdoba, Ciudad Universitaria, Pabellón Argentina, X5000HUA Córdoba, Argentina
- Centro Láser de Ciencias Moleculares, Universidad Nacional de Córdoba, Ciudad Universitaria, Pabellón Argentina, X5000HUA Córdoba, Argentina
| | - Jordan Dezalay
- Université Paris-Saclay, CNRS, Institut des Sciences Moléculaires d’Orsay, F-91405 Orsay, France
| | - Satchin Soorkia
- Université Paris-Saclay, CNRS, Institut des Sciences Moléculaires d’Orsay, F-91405 Orsay, France
| | - Michel Broquier
- Université Paris-Saclay, CNRS, Institut des Sciences Moléculaires d’Orsay, F-91405 Orsay, France
| | - Majdi Hochlaf
- Université Gustave Eiffel, COSYS/IMSE, 5 Bd Descartes 77454, Champs sur Marne, France
| | - Gustavo Ariel Pino
- INFIQC (CONICET-UNC), Ciudad Universitaria, Pabellón Argentina, 5000 Córdoba, Argentina
- Departamento de Fisicoquímica, Fac. de Ciencias Químicas, Universidad Nacional de Córdoba, Ciudad Universitaria, Pabellón Argentina, X5000HUA Córdoba, Argentina
| | - Gilles Grégoire
- Université Paris-Saclay, CNRS, Institut des Sciences Moléculaires d’Orsay, F-91405 Orsay, France
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9
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Marlton SJP, Trevitt A. Laser Photodissocation, Action Spectroscopy and Mass Spectrometry Unite to Detect and Separate Isomers. Chem Commun (Camb) 2022; 58:9451-9467. [DOI: 10.1039/d2cc02101c] [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 separation and detection of isomers remains a challenge for many areas of mass spectrometry. This article highlights laser photodissociation and ion mobility strategies that have been deployed to tackle...
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10
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Tureček F. Flying DNA Cation Radicals in the Gas Phase: Generation and Action Spectroscopy of Canonical and Noncanonical Nucleobase Forms. J Phys Chem B 2021; 125:7090-7100. [PMID: 34166596 DOI: 10.1021/acs.jpcb.1c03674] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Gas-phase chemistry of cation radicals related to ionized nucleic acids has enjoyed significant recent progress thanks to the development of new methods for cation radical generation, ion spectroscopy, and reactivity studies. Oxidative methods based on intramolecular electron transfer in transition-metal complexes have been used to generate nucleobase and nucleoside cation radicals. Reductive methods relying on intermolecular electron transfer in gas-phase ion-ion reactions have been utilized to generate a number of di- and tetranucleotide cation radicals, as well as charge-tagged nucleoside radicals. The generated cation radicals have been studied by infrared and UV-visible action spectroscopy and ab initio and density functional theory calculations, providing optimized structures, harmonic frequencies, and excited-state analysis. This has led to the discovery of stable noncanonical nucleobase cation radicals of unusual electronic properties and extremely low ion-electron recombination energies. Intramolecular proton-transfer reactions in cation radical oligonucleotides and Watson-Crick nucleoside pairs have been studied experimentally, and their mechanisms have been elucidated by theory. Whereas the range of applications of the oxidative methods is currently limited to nucleobases and readily oxidizable guanosine, the reductive methods can be scaled up to generate large oligonucleotide cation radicals including double-strand DNA. Challenges in the experimental and computational approach to DNA cation radicals are discussed.
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Affiliation(s)
- František Tureček
- Department of Chemistry, Bagley Hall, Box 351700, University of Washington, Seattle, Washington 98195-1700, United States
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11
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Huang SR, Tureček F. Cation Radicals of Hachimoji Nucleobases P and Z: Generation in the Gas Phase and Characterization by UV-Vis Photodissociation Action Spectroscopy and Theory. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2021; 32:373-386. [PMID: 33206519 DOI: 10.1021/jasms.0c00381] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
We report the generation of gas-phase cation radicals of unusual nucleobases 5-aza-7-deazaguanine (P) and 6-amino-5-nitro-(1H)pyrid-2-one (Z) that have been used as building blocks of base-expanded (hachimoji) DNA. The cation radicals were generated by collision-induced intramolecular electron transfer and dissociation of ternary copper-terpyridine complexes. The cation radicals were characterized by deuterium labeling and tandem mass spectrometry including MS3 collision-induced dissociation, UV-vis photodissociation, and action spectroscopy. Vibronic absorption UV-vis spectra were calculated by time-dependent density functional theory (TD-DFT) and compared with the action spectra to unequivocally assign the most closely matching structures for the gas-phase cation radicals. Ab initio calculations up to the coupled clusters-complete basis set (CCSD(T)/CBS) level of theory were used to rank by energy the P and Z neutral molecules and cation-radical isomers and provided transition-state and dissociation energies. The 5-aza-7-deazaguanine cation radicals were determined to have the canonical N-1-H, 6-oxo structure (P1+•) that was the global energy minimum within this group of isomers. The Z cation radicals were found to have the 1H-pyrid-2-one structure (Z1+•). The formation of P1+• and Z1+• was shown to be controlled by the solution thermodynamics of the Cu-terpyridine complexes and the kinetics of their dissociations. We also report and compare CCSD(T)/CBS-calculated adiabatic recombination energies of cation radicals for the entire hachimoji set of eight nucleobases, P+• (7.92 eV), Z+• (8.51 eV), S+• (8.51 eV), B+• (7.76 eV), T+• (8.98 eV), C+• (8.62 eV), A+• (8.32 eV), and G+• (7.97 eV), to assess the thermodynamics of base-to-base electron transfer following random ionization.
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Affiliation(s)
- Shu R Huang
- Department of Chemistry, University of Washington, Bagley Hall, Box 351700, Seattle, Washington 98195-1700, United States
| | - František Tureček
- Department of Chemistry, University of Washington, Bagley Hall, Box 351700, Seattle, Washington 98195-1700, United States
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12
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Huang SR, Tureček F. Cation Radicals of Hachimoji Nucleobases. Canonical Purine and Noncanonical Pyrimidine Forms Generated in the Gas Phase and Characterized by UV–Vis Photodissociation Action Spectroscopy. J Phys Chem A 2020; 124:7101-7112. [DOI: 10.1021/acs.jpca.0c06227] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Shu R. Huang
- Department of Chemistry, University of Washington, Bagley Hall, Box 351700, Seattle, Washington 98195-1700, United States
| | - František Tureček
- Department of Chemistry, University of Washington, Bagley Hall, Box 351700, Seattle, Washington 98195-1700, United States
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13
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Huang SR, Dang A, Tureček F. Ground and Excited States of Gas-Phase DNA Nucleobase Cation-Radicals. A UV-vis Photodisociation Action Spectroscopy and Computational Study of Adenine and 9-Methyladenine. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2020; 31:1271-1281. [PMID: 32324398 DOI: 10.1021/jasms.0c00095] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Cation radicals of adenine (A•+) and 9-methyladenine (MA•+) were generated in the gas phase by collision-induced intramolecular electron transfer in copper-terpyridine-nucleobase ternary complexes and characterized by collision-induced dissociation (CID) mass spectra and UV-vis photodissociation action spectroscopy in the 210-700 nm wavelength region. The action spectra of both A•+ and MA•+ displayed characteristic absorption bands in the near-UV and visible regions. Another tautomer of A•+ was generated as a minor product by multistep CID of protonated 9-(2-bromoethyl)adenine. Structure analysis by density functional theory and coupled-clusters ab initio calculations pointed to the canonical 9-H-tautomer Ad1•+ as the global energy minimum of adenine cation radicals. The canonical tautomer MA1•+ was also calculated to be a low-energy structure among methyladenine cation radicals. However, two new noncanonical tautomers were found to be energetically comparable to MA1•+. Vibronic absorption spectra were calculated for several tautomers of A•+ and MA•+ and benchmarked on equation-of-motion coupled-clusters excited-state calculations. Analysis of the vibronic absorption spectra of A•+ tautomers pointed to the canonical tautomer Ad1•+ as providing the best match with the action spectrum. Likewise, the canonical tautomer MA1•+ was the unequivocal best match for the MA•+ ion generated in the gas phase. According to potential-energy mapping, MA1•+ was separated from energetically favorable noncanonical cation radicals by a high-energy barrier that was calculated to be above the dissociation threshold for loss of a methyl hydrogen atom, thus preventing isomerization. Structures and energetics of all four DNA nucleobase cation radicals are compared and discussed.
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Affiliation(s)
- Shu R Huang
- Department of Chemistry, University of Washington, Bagley Hall, Box 351700, Seattle, Washington 98195-1700, United States
| | - Andy Dang
- Department of Chemistry, University of Washington, Bagley Hall, Box 351700, Seattle, Washington 98195-1700, United States
| | - František Tureček
- Department of Chemistry, University of Washington, Bagley Hall, Box 351700, Seattle, Washington 98195-1700, United States
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14
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Lee JU, Kim Y, Kim WY, Oh HB. Graph theory-based reaction pathway searches and DFT calculations for the mechanism studies of free radical-initiated peptide sequencing mass spectrometry (FRIPS MS): a model gas-phase reaction of GGR tri-peptide. Phys Chem Chem Phys 2020; 22:5057-5069. [PMID: 32073000 DOI: 10.1039/c9cp05433b] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Graph theory-based reaction pathway searches (ACE-Reaction program) and density functional theory calculations were performed to shed light on the mechanisms for the production of [an + H]+, xn+, yn+, zn+, and [yn + 2H]+ fragments formed in free radical-initiated peptide sequencing (FRIPS) mass spectrometry measurements of a small model system of glycine-glycine-arginine (GGR). In particular, the graph theory-based searches, which are rarely applied to gas-phase reaction studies, allowed us to investigate reaction mechanisms in an exhaustive manner without resorting to chemical intuition. As expected, radical-driven reaction pathways were favorable over charge-driven reaction pathways in terms of kinetics and thermodynamics. Charge- and radical-driven pathways for the formation of [yn + 2H]+ fragments were carefully compared, and it was revealed that the [yn + 2H]+ fragments observed in our FRIPS MS spectra originated from the radical-driven pathway, which is in contrast to the general expectation. The acquired understanding of the FRIPS fragmentation mechanism is expected to aid in the interpretation of FRIPS MS spectra. It should be emphasized that graph theory-based searches are powerful and effective methods for studying reaction mechanisms, including gas-phase reactions in mass spectrometry.
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Affiliation(s)
- Jae-Ung Lee
- Department of Chemistry, Sogang University, Seoul 04107, Republic of Korea.
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15
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Liu Y, Huang SR, Tureček F. Guanine–adenine interactions in DNA tetranucleotide cation radicals revealed by UV/vis photodissociation action spectroscopy and theory. Phys Chem Chem Phys 2020; 22:16831-16842. [DOI: 10.1039/d0cp02362k] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
Hydrogen-rich cation radicals (GATT + 2H)+˙ and (AGTT + 2H)+˙ represent oligonucleotide models of charged hydrogen atom adducts to DNA.
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Affiliation(s)
- Yue Liu
- Department of Chemistry
- University of Washington
- Seattle
- USA
| | - Shu R. Huang
- Department of Chemistry
- University of Washington
- Seattle
- USA
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16
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Dang A, Korn JA, Gladden J, Mozzone B, Tureček F. UV-Vis Photodissociation Action Spectroscopy on Thermo LTQ-XL ETD and Bruker amaZon Ion Trap Mass Spectrometers: a Practical Guide. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2019; 30:1558-1564. [PMID: 31087269 DOI: 10.1007/s13361-019-02229-z] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/14/2019] [Revised: 04/09/2019] [Accepted: 04/13/2019] [Indexed: 06/09/2023]
Abstract
We report automated procedures for multiple tandem mass spectra acquisition allowing UV-Vis photodissociation action spectroscopy measurements of ions and radicals. The procedures were developed for two commercial ion trap mass spectrometers and applied to collision-induced and electron-transfer dissociation tandem mass spectrometry modes of ion generation.
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Affiliation(s)
- Andy Dang
- Department of Chemistry, University of Washington, Bagley Hall, Box 351700, Seattle, WA, 98195-1700, USA
| | - Joseph A Korn
- Department of Chemistry, University of Washington, Bagley Hall, Box 351700, Seattle, WA, 98195-1700, USA
| | - James Gladden
- Department of Chemistry, University of Washington, Bagley Hall, Box 351700, Seattle, WA, 98195-1700, USA
| | - Brandon Mozzone
- Department of Chemistry, University of Washington, Bagley Hall, Box 351700, Seattle, WA, 98195-1700, USA
| | - František Tureček
- Department of Chemistry, University of Washington, Bagley Hall, Box 351700, Seattle, WA, 98195-1700, USA.
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17
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Segarra‐Martí J, Tran T, Bearpark MJ. Computing the Ultrafast and Radiationless Electronic Excited State Decay of Cytosine and 5‐methyl‐cytosine Cations: Uncovering the Role of Dynamic Electron Correlation. CHEMPHOTOCHEM 2019. [DOI: 10.1002/cptc.201900105] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Affiliation(s)
- Javier Segarra‐Martí
- Department of Chemistry, Molecular Sciences Research HubImperial College London White City Campus, 80 Wood Lane W12 0BZ London UK
| | - Thierry Tran
- Department of Chemistry, Molecular Sciences Research HubImperial College London White City Campus, 80 Wood Lane W12 0BZ London UK
| | - Michael J. Bearpark
- Department of Chemistry, Molecular Sciences Research HubImperial College London White City Campus, 80 Wood Lane W12 0BZ London UK
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18
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Zhu G, Qian C, Wang L. Tautomer‐Specific Resonant Photoelectron Imaging of Deprotonated Cytosine Anions. Angew Chem Int Ed Engl 2019. [DOI: 10.1002/ange.201903444] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Guo‐Zhu Zhu
- Department of Chemistry Brown University Providence RI 02912 USA
| | - Chen‐Hui Qian
- Department of Chemistry Brown University Providence RI 02912 USA
| | - Lai‐Sheng Wang
- Department of Chemistry Brown University Providence RI 02912 USA
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19
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Zhu G, Qian C, Wang L. Tautomer‐Specific Resonant Photoelectron Imaging of Deprotonated Cytosine Anions. Angew Chem Int Ed Engl 2019; 58:7856-7860. [DOI: 10.1002/anie.201903444] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2019] [Indexed: 11/08/2022]
Affiliation(s)
- Guo‐Zhu Zhu
- Department of ChemistryBrown University Providence RI 02912 USA
| | - Chen‐Hui Qian
- Department of ChemistryBrown University Providence RI 02912 USA
| | - Lai‐Sheng Wang
- Department of ChemistryBrown University Providence RI 02912 USA
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20
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Dang A, Liu Y, Tureček F. UV–Vis Action Spectroscopy of Guanine, 9-Methylguanine, and Guanosine Cation Radicals in the Gas Phase. J Phys Chem A 2019; 123:3272-3284. [DOI: 10.1021/acs.jpca.9b01542] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Affiliation(s)
- Andy Dang
- Department of Chemistry, University of Washington, Bagley Hall,
Box 351700, Seattle, Washington 98195-1700, United States
| | - Yue Liu
- Department of Chemistry, University of Washington, Bagley Hall,
Box 351700, Seattle, Washington 98195-1700, United States
| | - František Tureček
- Department of Chemistry, University of Washington, Bagley Hall,
Box 351700, Seattle, Washington 98195-1700, United States
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21
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Raczyńska ED, Juras W. Effects of ionization and proton-transfer on bond length alternation in favored and rare isomers of isocytosine. COMPUT THEOR CHEM 2019. [DOI: 10.1016/j.comptc.2018.12.010] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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22
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Liu Y, Korn JA, Dang A, Tureček F. Hydrogen-Rich Cation Radicals of DNA Dinucleotides: Generation and Structure Elucidation by UV-Vis Action Spectroscopy. J Phys Chem B 2018; 122:9665-9680. [PMID: 30269486 DOI: 10.1021/acs.jpcb.8b07925] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Hydrogen-rich DNA dinucleotide cation radicals (dGG + 2H)+•, (dCG + 2H)+•, and (dGC + 2H)+• represent transient species comprising protonated and hydrogen atom adducted nucleobase rings that serve as models for proton and radical migrations in ionized DNA. These DNA cation radicals were generated in the gas phase by electron-transfer dissociation of dinucleotide dication-crown-ether complexes and characterized by UV-vis photodissociation action spectra, ab initio calculations of structures and relative energies, and time-dependent density functional theory calculations of UV-vis absorption spectra. Theoretical calculations indicate that (dGG + 2H)+• cation radicals formed by electron transfer underwent an exothermic conformational collapse that was accompanied by guanine ring stacking and facile internucleobase hydrogen atom transfer, forming 3'-guanine C-8-H radicals. In contrast, exothermic hydrogen transfer from the 5'-cytosine radical onto the guanine ring in (dCG + 2H)+• was kinetically hampered, resulting in the formation of a mixture of 5'-cytosine and 3'-guanine radicals. Conformational folding and nucleobase stacking were energetically unfavorable in (dGC + 2H)+• that retained its structure of a 3'-cytosine radical, as formed by one-electron reduction of the dication. Hydrogen-rich guanine (G + H)• and cytosine (C + H)• radicals were calculated to have vastly different basicities in water, as illustrated by the respective p Ka values of 20.0 and 4.6, which is pertinent to their different abilities to undergo proton-transfer reactions in solution.
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Affiliation(s)
- Yang Liu
- Department of Chemistry, Bagley Hall , University of Washington , P.O. Box 351700, Seattle , Washington 98195-1700 , United States
| | - Joseph A Korn
- Department of Chemistry, Bagley Hall , University of Washington , P.O. Box 351700, Seattle , Washington 98195-1700 , United States
| | - Andy Dang
- Department of Chemistry, Bagley Hall , University of Washington , P.O. Box 351700, Seattle , Washington 98195-1700 , United States
| | - František Tureček
- Department of Chemistry, Bagley Hall , University of Washington , P.O. Box 351700, Seattle , Washington 98195-1700 , United States
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23
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Raczyńska ED, Makowski M. Effects of Positive and Negative Ionization on Prototropy in Pyrimidine Bases: An Unusual Case of Isocytosine. J Phys Chem A 2018; 122:7863-7879. [PMID: 30192141 DOI: 10.1021/acs.jpca.8b07539] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Intramolecular proton-transfers (prototropic conversions) have been studied for the guanine building block isocytosine (iC), and effects of positive ionization, called one-electron oxidation (iC - e → iC+•), and negative ionization, called one-electron reduction (iC + e → iC-•), on tautomeric conversions when proceeding from neutral to ionized isocytosine have been discussed. Although radical cations and radical anions are very short-lived species, the ionization effects could be investigated by quantum-chemical methods. Such kind of studies gives some information about the labile protons and the most basic positions in the neutral and radical forms of the tautomeric system. For investigations, the complete isomeric mixture of isocytosine has been considered and calculations performed in two extreme environments, apolar {DFT(B3LYP)/6-311+G(d,p)} and polar {PCM(water)//DFT(B3LYP)/6-311+G(d,p)}. For selected isomers, the G4 theory has also been applied. There are no good relations for energetic parameters of neutral and ionized forms. Ionization energies depend on localization of labile protons. Tautomeric equilibria for neutral and ionized isocytosine, favored sites of protonation and deprotonation, and favored structures of protonated and deprotonated forms strongly depend on environment. Acidity of iC+• is close to that of the iC conjugate acid, and basicity of iC-• is close to that of the iC conjugate base. This increase of acid-base properties of charged radicals explains the proton-transfer in ionized pairs of nucleobases. When compared to other pyrimidine bases such as uracil (U) and cytosine (C), which exhibit analogous tautomeric equilibria between nine prototropic tautomers as isocytosine, the tautomeric preferences for iC, iC+•, iC-•, U, U+•, U-•, C, C+•, and C-• are completely different. The differences suggest that acid-base properties of functional groups, their stabilities, and ionization energies play a principal role in proton-transfers for pyrimidine bases and influence compositions of tautomeric mixtures.
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Affiliation(s)
- Ewa D Raczyńska
- Department of Chemistry , Warsaw University of Life Sciences (SGGW) , ul. Nowoursynowska 159c , 02-776 Warszawa , Poland
| | - Mariusz Makowski
- Faculty of Chemistry , University of Gdańsk , ul. Wita Stwosza 63 , 80-308 Gdańsk , Poland
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24
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Ranka K, Zhao N, Yu L, Stanton JF, Polfer NC. Radical Rearrangement Chemistry in Ultraviolet Photodissociation of Iodotyrosine Systems: Insights from Metastable Dissociation, Infrared Ion Spectroscopy, and Reaction Pathway Calculations. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2018; 29:1791-1801. [PMID: 29845561 DOI: 10.1007/s13361-018-1959-1] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/26/2018] [Revised: 03/21/2018] [Accepted: 04/01/2018] [Indexed: 06/08/2023]
Abstract
We report on the ultraviolet photodissociation (UVPD) chemistry of protonated tyrosine, iodotyrosine, and diiodotyrosine. Distonic loss of the iodine creates a high-energy radical at the aromatic ring that engages in hydrogen/proton rearrangement chemistry. Based on UVPD kinetics measurements, the appearance of this radical is coincident with the UV irradiation pulse (8 ns). Conversely, sequential UVPD product ions exhibit metastable decay on ca. 100 ns timescales. Infrared ion spectroscopy is capable of confirming putative structures of the rearrangement products as proton transfers from the imine and β-carbon hydrogens. Potential energy surfaces for the various reaction pathways indicate that the rearrangement chemistry is highly complex, compatible with a cascade of rearrangements, and that there is no preferred rearrangement pathway even in small molecular systems like these. Graphical Abstract.
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Affiliation(s)
- Karnamohit Ranka
- Quantum Theory Project, Department of Chemistry, University of Florida, P.O. Box 117200, Gainesville, FL, 32611-7200, USA
- Quantum Theory Project, Department of Physics, University of Florida, P.O. Box 118435, Gainesville, FL, 32611-8435, USA
| | - Ning Zhao
- Department of Chemistry and Center for Chemical Physics, University of Florida, P.O. Box 117200, Gainesville, FL, 32611-7200, USA
| | - Long Yu
- Department of Chemistry and Center for Chemical Physics, University of Florida, P.O. Box 117200, Gainesville, FL, 32611-7200, USA
| | - John F Stanton
- Quantum Theory Project, Department of Chemistry, University of Florida, P.O. Box 117200, Gainesville, FL, 32611-7200, USA
- Quantum Theory Project, Department of Physics, University of Florida, P.O. Box 118435, Gainesville, FL, 32611-8435, USA
| | - Nicolas C Polfer
- Department of Chemistry and Center for Chemical Physics, University of Florida, P.O. Box 117200, Gainesville, FL, 32611-7200, USA.
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25
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Wang X, Zhou Z, Tang Y, Chen J, Zhong D, Jianhua Xu. Excited State Decay Pathways of 2'-Deoxy-5-methylcytidine and Deoxycytidine Revisited in Solution: A Comprehensive Kinetic Study by Femtosecond Transient Absorption. J Phys Chem B 2018; 122:7027-7037. [PMID: 29939745 DOI: 10.1021/acs.jpcb.8b00927] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Methylated cytosine is proved to have an important role as an epigenetic signal in gene regulation and is often referred to "the fifth base of DNA". A comprehensive understanding of the electronic excited state relaxation in cytosine and its methylated derivatives is crucial for revealing UV-induced photodamage to the biological genome. Because of the existence of multiple closely lying "bright" and "dark" excited states, the decay pathways in these DNA nucleosides are the most complex and the least understood so far. In this study, femtosecond transient absorption with different excitation wavelengths (240-296 nm) was used to study the relaxation of excited electronic states of 5-methylcytosine (5mC) and 2'-deoxy-5-methylcytidine (5mdCyd) in phosphate buffered aqueous solution and in acetonitrile solution. Two distinct nonradiative decay channels were directly observed. The first one is a several picosecond internal conversion channel that involves two bright ππ* states (ππ*2 and ππ*1) when ππ*2 state is initially populated. The second channel contains the lower energy ππ*1 state and a so far experimental unidentified long-lived state which exhibits a several nanosecond lifetime. The long-lived state can only be accessed by the initially excited ππ*1 state. Inspired by this new discovery in 5mC and 5mdCyd, we revisited the decay of excited state of 2'-deoxycytidine (dCyd), revealing very similar decay pathways. Additionally, a well-known dark nOπ* state (carbonyl lone pair) with ∼30 ps lifetime is present in both decay channels in dCyd. With our detailed experimental results, we successfully reconcile the long history debate of cytosine excited state relaxation mechanism by pointing out that the reason for the complex dynamics under traditional 266 nm excitation is mixed signals from the above-mentioned two distinct decay pathways. Our findings lead to a dramatically different and new picture of electronic energy relaxation in 5mdCyd/dCyd and could help to understand photostability as well as UV-induced photodamage of these nucleotides and related DNAs.
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Affiliation(s)
- Xueli Wang
- State Key Laboratory of Precision Spectroscopy , East China Normal University , Shanghai , 200062 China
| | - Zhongneng Zhou
- State Key Laboratory of Precision Spectroscopy , East China Normal University , Shanghai , 200062 China
| | - Yuankai Tang
- State Key Laboratory of Precision Spectroscopy , East China Normal University , Shanghai , 200062 China
| | - Jinquan Chen
- State Key Laboratory of Precision Spectroscopy , East China Normal University , Shanghai , 200062 China.,Collaborative Innovation Center of Extreme Optics , Shanxi University , Taiyuan , Shanxi 030006 , China
| | - Dongping Zhong
- Department of Physics, Department of Chemistry and Biochemistry, and Programs of Biophysics, Chemical Physics, and Biochemistry , The Ohio State University , Columbus , Ohio 43210 , United States
| | - Jianhua Xu
- State Key Laboratory of Precision Spectroscopy , East China Normal University , Shanghai , 200062 China.,Collaborative Innovation Center of Extreme Optics , Shanxi University , Taiyuan , Shanxi 030006 , China
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26
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Tankovskaia SA, Kotb OM, Dommes OA, Paston SV. Application of spectral methods for studying DNA damage induced by gamma-radiation. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2018; 200:85-92. [PMID: 29674243 DOI: 10.1016/j.saa.2018.04.011] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/27/2017] [Revised: 04/05/2018] [Accepted: 04/06/2018] [Indexed: 06/08/2023]
Abstract
Spectral methods can provide a variety of possibilities to determine several types of radiation-induced DNA damage, such as nucleobase destruction and local denaturation. DNA UV absorption and CD spectra measured at room temperature undergo noticeable alteration under the action of γ-radiation. We have applied the Spirin method of total nucleobases determination, and have measured the molar extinction coefficient of DNA and DNA CD spectra for solutions with different NaCl concentrations (3mM-3.2M) and containing MgCl2, exposed to γ-radiation with the doses of 0-103Gy. The melting temperatures of DNA in irradiated solutions at the doses of 0-50Gy were obtained with the help of spectrophotometric melting. It was found that the amount of destructed nucleobases and radiation-induced loss of DNA helicity significantly decreases with the rise of the ionic strength of the irradiated solution. Substitution of a portion of Na+ ions on Mg2+ while keeping the total ionic strength constant (μ=5mM) does not affect the considered radiation effects. The role of the structure and composition of the DNA secondary hydration layer in the radiation-induced damages is discussed.
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Affiliation(s)
- Svetlana A Tankovskaia
- Department of Molecular Biophysics and Polymer Physics, Faculty of Physics, Saint-Petersburg State University, Ulyanovskaya, 3, St. Petersburg 198504, Russia
| | - Omar M Kotb
- Department of Molecular Biophysics and Polymer Physics, Faculty of Physics, Saint-Petersburg State University, Ulyanovskaya, 3, St. Petersburg 198504, Russia; Department of Physics, Faculty of Science, Zagazig University, Sharkia Gov, Zagazig 44519, Egypt
| | - Olga A Dommes
- Institute of Macromolecular Compounds, Bolshoy pr. 31, 199004 Saint-Petersburg, Russia
| | - Sofia V Paston
- Department of Molecular Biophysics and Polymer Physics, Faculty of Physics, Saint-Petersburg State University, Ulyanovskaya, 3, St. Petersburg 198504, Russia.
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27
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Jašíková L, Roithová J. Infrared Multiphoton Dissociation Spectroscopy with Free-Electron Lasers: On the Road from Small Molecules to Biomolecules. Chemistry 2018; 24:3374-3390. [PMID: 29314303 DOI: 10.1002/chem.201705692] [Citation(s) in RCA: 54] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2017] [Indexed: 01/07/2023]
Abstract
Infrared multiphoton dissociation (IRMPD) spectroscopy is commonly used to determine the structure of isolated, mass-selected ions in the gas phase. This method has been widely used since it became available at free-electron laser (FEL) user facilities. Thus, in this Minireview, we examine the use of IRMPD/FEL spectroscopy for investigating ions derived from small molecules, metal complexes, organometallic compounds and biorelevant ions. Furthermore, we outline new applications of IRMPD spectroscopy to study biomolecules.
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Affiliation(s)
- Lucie Jašíková
- Department of Organic Chemistry, Faculty of Science, Charles University, Hlavova 2030, Prague 2, 128 43, Czech Republic
| | - Jana Roithová
- Department of Organic Chemistry, Faculty of Science, Charles University, Hlavova 2030, Prague 2, 128 43, Czech Republic
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28
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Dang A, Nguyen HTH, Ruiz H, Piacentino E, Ryzhov V, Tureček F. Experimental Evidence for Noncanonical Thymine Cation Radicals in the Gas Phase. J Phys Chem B 2017; 122:86-97. [DOI: 10.1021/acs.jpcb.7b09872] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Affiliation(s)
- Andy Dang
- Department
of Chemistry, University of Washington, Bagley Hall, Box 351700, Seattle, Washington 98195-1700, United States
| | - Huong T. H. Nguyen
- Department
of Chemistry, University of Washington, Bagley Hall, Box 351700, Seattle, Washington 98195-1700, United States
| | - Heather Ruiz
- Department
of Chemistry and Biochemistry, Northern Illinois University, DeKalb, Illinois 60115, United States
| | - Elettra Piacentino
- Department
of Chemistry and Biochemistry, Northern Illinois University, DeKalb, Illinois 60115, United States
| | - Victor Ryzhov
- Department
of Chemistry and Biochemistry, Northern Illinois University, DeKalb, Illinois 60115, United States
| | - František Tureček
- Department
of Chemistry, University of Washington, Bagley Hall, Box 351700, Seattle, Washington 98195-1700, United States
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29
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Korn JA, Urban J, Dang A, Nguyen HTH, Tureček F. UV-Vis Action Spectroscopy Reveals a Conformational Collapse in Hydrogen-Rich Dinucleotide Cation Radicals. J Phys Chem Lett 2017; 8:4100-4107. [PMID: 28809578 DOI: 10.1021/acs.jpclett.7b01856] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
We report the generation of deoxyriboadenosine dinucleotide cation radicals by gas-phase electron transfer to dinucleotide dications and their noncovalent complexes with crown ether ligands. Stable dinucleotide cation radicals of a novel hydrogen-rich type were generated and characterized by tandem mass spectrometry and UV-vis photodissociation (UVPD) action spectroscopy. Electron structure theory analysis indicated that upon electron attachment the dinucleotide dications underwent a conformational collapse followed by intramolecular proton migrations between the nucleobases to give species whose calculated UV-vis absorption spectra matched the UVPD action spectra. Hydrogen-rich cation radicals generated from chimeric riboadenosine 5'-diesters gave UVPD action spectra that pointed to novel zwitterionic structures consisting of aromatic π-electron anion radicals intercalated between stacked positively charged adenine rings. Analogies with DNA ionization are discussed.
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Affiliation(s)
- Joseph A Korn
- Department of Chemistry, University of Washington , Bagley Hall, Seattle, Washington 98195-1700, United States
| | - Jan Urban
- Metagenics, Inc. , Gig Harbor, Washington 98335-3729, United States
| | - Andy Dang
- Department of Chemistry, University of Washington , Bagley Hall, Seattle, Washington 98195-1700, United States
| | - Huong T H Nguyen
- Department of Chemistry, University of Washington , Bagley Hall, Seattle, Washington 98195-1700, United States
| | - František Tureček
- Department of Chemistry, University of Washington , Bagley Hall, Seattle, Washington 98195-1700, United States
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