1
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Datta M, Szczyrba A, Zdrowowicz M, Wyrzykowski D, Ciupak O, Demkowicz S, Izadi F, Denifl S, Rak J. Surprising Radiolytic Stability of 8-Thiomethyladenine in an Aqueous Solution. J Phys Chem B 2024; 128:3621-3630. [PMID: 38578255 PMCID: PMC11033863 DOI: 10.1021/acs.jpcb.4c01033] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2024] [Revised: 03/18/2024] [Accepted: 03/20/2024] [Indexed: 04/06/2024]
Abstract
8-Thiomethyladenine (ASCH3), a potentially radiosensitizing modified nucleobase, has been synthesized in a reaction between 8-thioadenine and methyl iodide. Despite favorable dissociative electron attachment (DEA) characteristics, the radiolysis of an aqueous solution of ASCH3 with a dose of X-ray amounting to as much as 300 Gy leads to no effects. Nevertheless, crossed electron-molecule beam experiments in the gas phase on ASCH3 confirm the theoretical findings regarding the stability of its radical anion, namely, the most abundant reaction channel is related to the dissociation of the S-CH3 bond in the respective anion. Furthermore, electron-induced degradation of ASCH3 has been observed in aprotic acetonitrile, which is strong evidence for the involvement of proton transfer (PT) in stabilizing the radical anion in an aqueous solution. These findings demonstrate that PT in water can be the main player in deciding the radiosensitizing properties of modified nucleobases/nucleosides.
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Affiliation(s)
- Magdalena Datta
- Faculty
of Chemistry, University of Gdańsk, Wita Stwosza 63, Gdańsk 80-308, Poland
| | - Adrian Szczyrba
- Faculty
of Chemistry, University of Gdańsk, Wita Stwosza 63, Gdańsk 80-308, Poland
| | - Magdalena Zdrowowicz
- Faculty
of Chemistry, University of Gdańsk, Wita Stwosza 63, Gdańsk 80-308, Poland
| | - Dariusz Wyrzykowski
- Faculty
of Chemistry, University of Gdańsk, Wita Stwosza 63, Gdańsk 80-308, Poland
| | - Olga Ciupak
- Department
of Organic Chemistry, Faculty of Chemistry, Gdańsk University of Technology, Narutowicza 11/12, 80-233 Gdańsk, Poland
| | - Sebastian Demkowicz
- Department
of Organic Chemistry, Faculty of Chemistry, Gdańsk University of Technology, Narutowicza 11/12, 80-233 Gdańsk, Poland
| | - Farhad Izadi
- Institut
für Ionenphysik und Angewandte Physik and Center for Biomolecular
Sciences Innsbruck, Universität Innsbruck, Technikerstrasse 25, A-6020 Innsbruck, Austria
| | - Stephan Denifl
- Institut
für Ionenphysik und Angewandte Physik and Center for Biomolecular
Sciences Innsbruck, Universität Innsbruck, Technikerstrasse 25, A-6020 Innsbruck, Austria
| | - Janusz Rak
- Faculty
of Chemistry, University of Gdańsk, Wita Stwosza 63, Gdańsk 80-308, Poland
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2
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The Two Faces of the Guanyl Radical: Molecular Context and Behavior. Molecules 2021; 26:molecules26123511. [PMID: 34207639 PMCID: PMC8227002 DOI: 10.3390/molecules26123511] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2021] [Revised: 05/29/2021] [Accepted: 06/01/2021] [Indexed: 12/16/2022] Open
Abstract
The guanyl radical or neutral guanine radical G(-H)• results from the loss of a hydrogen atom (H•) or an electron/proton (e–/H+) couple from the guanine structures (G). The guanyl radical exists in two tautomeric forms. As the modes of formation of the two tautomers, their relationship and reactivity at the nucleoside level are subjects of intense research and are discussed in a holistic manner, including time-resolved spectroscopies, product studies, and relevant theoretical calculations. Particular attention is given to the one-electron oxidation of the GC pair and the complex mechanism of the deprotonation vs. hydration step of GC•+ pair. The role of the two G(-H)• tautomers in single- and double-stranded oligonucleotides and the G-quadruplex, the supramolecular arrangement that attracts interest for its biological consequences, are considered. The importance of biomarkers of guanine DNA damage is also addressed.
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3
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Taras-Goslinska K, Vetica F, Barata-Vallejo S, Triantakostanti V, Marciniak B, Chatgilialoglu C. Converging Fate of the Oxidation and Reduction of 8-Thioguanosine. Molecules 2019; 24:E3143. [PMID: 31470553 PMCID: PMC6749358 DOI: 10.3390/molecules24173143] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2019] [Revised: 08/27/2019] [Accepted: 08/28/2019] [Indexed: 11/16/2022] Open
Abstract
Thione-containing nucleobases have attracted the attention of the scientific community for their application in oncology, virology, and transplantology. The detailed understanding of the reactivity of the purine derivative 8-thioguanosine (8-TG) with reactive oxygen species (ROS) and free radicals is crucial for its biological relevance. An extensive investigation on the fate of 8-TG under both reductive and oxidative conditions is here reported, and it was tested by employing steady-state photooxidation, laser flash photolysis, as well as γ-radiolysis in aqueous solutions. The characterization of the 8-TG T1 excited state by laser flash photolysis and the photooxidation experiments confirmed that singlet oxygen is a crucial intermediate in the formation of the unexpected reduced product guanosine, without the formation of the usual oxygenated sulfinic or sulfonic acids. Furthermore, a thorough screening of different radiolytic conditions upon γ-radiation afforded the reduced product. These results were rationalized by performing control experiments in the predominant presence of each reactive species formed by radiolysis of water, and the mechanistic pathway scenario was postulated on these bases.
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Affiliation(s)
| | - Fabrizio Vetica
- R&D Laboratory, Lipinutragen srl, Via Piero Gobetti 101, 40129 Bologna, Italy
- ISOF, Consiglio Nazionale delle Ricerche, Via Piero Gobetti 101, 40129 Bologna, Italy
| | - Sebastián Barata-Vallejo
- ISOF, Consiglio Nazionale delle Ricerche, Via Piero Gobetti 101, 40129 Bologna, Italy
- Universidad de Buenos Aires, Facultad de Farmacia y Bioquimíca, Departamento de Quimíca Organíca, Junin 954, RA-1113 Buenos Aires, Argentina
| | | | - Bronisław Marciniak
- Adam Mickiewicz University, Faculty of Chemistry, Wieniawskiego 1, 61-712 Poznań, Poland
- Center of Advanced Technologies, Adam Mickiewicz University, 61-712 Poznań, Poland
| | - Chryssostomos Chatgilialoglu
- R&D Laboratory, Lipinutragen srl, Via Piero Gobetti 101, 40129 Bologna, Italy.
- ISOF, Consiglio Nazionale delle Ricerche, Via Piero Gobetti 101, 40129 Bologna, Italy.
- Center of Advanced Technologies, Adam Mickiewicz University, 61-712 Poznań, Poland.
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4
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Rak J, Chomicz L, Wiczk J, Westphal K, Zdrowowicz M, Wityk P, Żyndul M, Makurat S, Golon Ł. Mechanisms of Damage to DNA Labeled with Electrophilic Nucleobases Induced by Ionizing or UV Radiation. J Phys Chem B 2015; 119:8227-38. [PMID: 26061614 DOI: 10.1021/acs.jpcb.5b03948] [Citation(s) in RCA: 60] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Hypoxia--a hallmark of solid tumors--makes hypoxic cells radioresistant. On the other hand, DNA, the main target of anticancer therapy, is not sensitive to the near UV photons and hydrated electrons, one of the major products of water radiolysis under hypoxic conditions. A possible way to overcome these obstacles to the efficient radio- and photodynamic therapy of cancer is to sensitize the cellular DNA to electrons and/or ultraviolet radiation. While incorporated into genomic DNA, modified nucleosides, 5-bromo-2'-deoxyuridine in particular, sensitize cells to both near-ultraviolet photons and γ rays. It is believed that, in both sensitization modes, the reactive nucleobase radical is formed as a primary product which swiftly stabilizes, leading to serious DNA damage, like strand breaks or cross-links. However, despite the apparent similarity, such radio- and photosensitization of DNA seems to be ruled by fundamentally different mechanisms. In this review, we demonstrate that the most important factors deciding on radiodamage to the labeled DNA are (i) the electron affinity (EA) of modified nucleoside (mNZ), (ii) the local surroundings of the label that significantly influences the EA of mNZ, and (iii) the strength of the chemical bond holding together the substituent and a nucleobase. On the other hand, we show that the UV damage to sensitized DNA is governed by long-range photoinduced electron transfer, the efficiency of which is controlled by local DNA sequences. A critical review of the literature mechanisms concerning both types of damage to the labeled biopolymer is presented. Ultimately, the perspectives of studies on DNA sensitization in the context of cancer therapy are discussed.
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Affiliation(s)
- Janusz Rak
- Faculty of Chemistry University of Gdańsk, Wita Stwosza 63, 80-308 Gdańsk, Poland
| | - Lidia Chomicz
- Faculty of Chemistry University of Gdańsk, Wita Stwosza 63, 80-308 Gdańsk, Poland
| | - Justyna Wiczk
- Faculty of Chemistry University of Gdańsk, Wita Stwosza 63, 80-308 Gdańsk, Poland
| | - Kinga Westphal
- Faculty of Chemistry University of Gdańsk, Wita Stwosza 63, 80-308 Gdańsk, Poland
| | - Magdalena Zdrowowicz
- Faculty of Chemistry University of Gdańsk, Wita Stwosza 63, 80-308 Gdańsk, Poland
| | - Paweł Wityk
- Faculty of Chemistry University of Gdańsk, Wita Stwosza 63, 80-308 Gdańsk, Poland
| | - Michał Żyndul
- Faculty of Chemistry University of Gdańsk, Wita Stwosza 63, 80-308 Gdańsk, Poland
| | - Samanta Makurat
- Faculty of Chemistry University of Gdańsk, Wita Stwosza 63, 80-308 Gdańsk, Poland
| | - Łukasz Golon
- Faculty of Chemistry University of Gdańsk, Wita Stwosza 63, 80-308 Gdańsk, Poland
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5
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Westphal K, Wiczk J, Miloch J, Kciuk G, Bobrowski K, Rak J. Irreversible electron attachment – a key to DNA damage by solvated electrons in aqueous solution. Org Biomol Chem 2015; 13:10362-9. [DOI: 10.1039/c5ob01542a] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
In an aqueous solution trinucleotides labeled with bromonucleobases are damaged by ionizing radiation induced electrons while native trimers are insensitive to electrons under the same conditions.
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Affiliation(s)
- K. Westphal
- Faculty of Chemistry
- University of Gdańsk
- 80-308 Gdańsk
- Poland
| | - J. Wiczk
- Faculty of Chemistry
- University of Gdańsk
- 80-308 Gdańsk
- Poland
| | - J. Miloch
- Faculty of Chemistry
- University of Gdańsk
- 80-308 Gdańsk
- Poland
| | - G. Kciuk
- Centre of Radiation Research and Technology
- Institute of Nuclear Chemistry and Technology
- 03-195 Warsaw
- Poland
| | - K. Bobrowski
- Centre of Radiation Research and Technology
- Institute of Nuclear Chemistry and Technology
- 03-195 Warsaw
- Poland
| | - J. Rak
- Faculty of Chemistry
- University of Gdańsk
- 80-308 Gdańsk
- Poland
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6
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Chomicz L, Rak J, Storoniak P. Electron-induced elimination of the bromide anion from brominated nucleobases. A computational study. J Phys Chem B 2012; 116:5612-9. [PMID: 22510158 DOI: 10.1021/jp3008738] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
The enhancement of radiodamage to DNA labeled with halonucleobases is attributed to the reactive radical produced from a halonucleobase by the attachment of an electron. We examined at the B3LYP/6-31++G** level electron capture by four brominated nucleobases (BrNBs): 8-bromo-9-methyladenine, 8-bromo-9-methylguanine, 5-bromo-1-methylcytosine, and 5-bromo-1-methyluracil followed by the release of the bromide anion and a nucleobase radical. We demonstrate that neutral BrNBs in both gas and aqueous phases are better electron acceptors than unsubstituted NBs and that resulting anion radicals, BrNBs(•-), can easily transform into the product complex of the bromide anion and the nucleobase radical ([Br(-)···NB(•)]). The overall thermodynamic stimulus for the process starting with the neutral BrNB and ending with the isolated bromide anion and the NB(•) radical is similar in the case of all four BrNBs studied, which suggests their comparable radiosensitizing capabilities.
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Affiliation(s)
- Lidia Chomicz
- Department of Chemistry, University of Gdańsk , Sobieskiego 18, 80-952 Gdańsk, Poland
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7
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Saftić D, Žinić B, Višnjevac A. DBU induced formation of 8-bromoguanosine dimer with three hydrogen bonds between the GG− base pairs. Tetrahedron 2012. [DOI: 10.1016/j.tet.2011.11.086] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/14/2022]
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8
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Kiliszek A, Kierzek R, Krzyzosiak WJ, Rypniewski W. Crystal structures of CGG RNA repeats with implications for fragile X-associated tremor ataxia syndrome. Nucleic Acids Res 2011; 39:7308-15. [PMID: 21596781 PMCID: PMC3167596 DOI: 10.1093/nar/gkr368] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
The CGG repeats are present in the 5'-untranslated region (5'-UTR) of the fragile X mental retardation gene FMR1 and are associated with two diseases: fragile X-associated tremor ataxia syndrome (FXTAS) and fragile X syndrome (FXS). FXTAS occurs when the number of repeats is 55-200 and FXS develops when the number exceeds 200. FXTAS is an RNA-mediated disease in which the expanded CGG tracts form stable structures and sequester important RNA binding proteins. We obtained and analysed three crystal structures of double-helical CGG repeats involving unmodified and 8-Br modified guanosine residues. Despite the presence of the non-canonical base pairs, the helices retain an A-form. In the G-G pairs one guanosine is always in the syn conformation, the other is anti. There are two hydrogen bonds between the Watson-Crick edge of G(anti) and the Hoogsteen edge of G(syn): O6·N1H and N7·N2H. The G(syn)-G(anti) pair shows affinity for binding ions in the major groove. G(syn) causes local unwinding of the helix, compensated elsewhere along the duplex. CGG helical structures appear relatively stable compared with CAG and CUG tracts. This could be an important factor in the RNA's ligand binding affinity and specificity.
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Affiliation(s)
| | | | | | - Wojciech Rypniewski
- *To whom correspondence should be addressed. Tel: +48-61-8528503; Fax: +48-61-8520532;
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9
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Chatgilialoglu C, Caminal C, Mulazzani QG. Radical-based alkylation of guanine derivatives in aqueous medium. Org Biomol Chem 2011; 9:3494-8. [DOI: 10.1039/c0ob01264e] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
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10
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Fazio D, Trindler C, Heil K, Chatgilialoglu C, Carell T. Investigation of excess-electron transfer in DNA double-duplex systems allows estimation of absolute excess-electron transfer and CPD cleavage rates. Chemistry 2010; 17:206-12. [PMID: 21207617 DOI: 10.1002/chem.201001978] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2010] [Indexed: 11/09/2022]
Abstract
To investigate the parameters and rates that determine excess-electron transfer processes in DNA duplexes, we developed a DNA double-duplex system containing a reduced and deprotonated flavin donor at the junction of two duplexes with either the same or different electron acceptors in the individual duplex substructures. This model system allows us to bring the two electron acceptors in the duplex substructures into direct competition for injected electrons and this enables us to decipher how the kind of acceptor influences the transfer data. Measurements with the electron acceptors 8-bromo-dA (BrdA), 8-bromo-dG (BrdG), 5-bromo-dU (BrdU), and a cyclobutane pyrimidine dimer, which is a UV-induced DNA lesion, allowed us to obtain directly the maximum overall reaction rates of these acceptors and especially of the T=T dimer with the injected electrons in the duplex. In line with previous observations, we detected that the overall dimer cleavage rate is about one order of magnitude slower than the debromination of BrdU. Furthermore, we present a more detailed explanation of why sequence dependence cannot be observed when a T=T dimer is used as the acceptor and we estimate the absolute excess-electron hopping rates.
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Affiliation(s)
- Danila Fazio
- Department of Chemistry and Biochemistry, Ludwig-Maximilians-University Munich, Butenandtstrasse 5-13, Haus F, 81377 Munich, Germany
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11
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Kaloudis P, D'Angelantonio M, Guerra M, Gimisis T, Mulazzani QG, Chatgilialoglu C. One-Electron Reduction of 8-Bromo-2-aminoadenosine in the Aqueous Phase: Radiation Chemical and DFT Studies of the Mechanism. J Phys Chem B 2008; 112:5209-17. [DOI: 10.1021/jp800480f] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Panagiotis Kaloudis
- ISOF, Consiglio Nazionale delle Ricerche, Via P. Gobetti 101, 40129 Bologna, Italy
| | - Mila D'Angelantonio
- ISOF, Consiglio Nazionale delle Ricerche, Via P. Gobetti 101, 40129 Bologna, Italy
| | - Maurizio Guerra
- ISOF, Consiglio Nazionale delle Ricerche, Via P. Gobetti 101, 40129 Bologna, Italy
| | - Thanasis Gimisis
- ISOF, Consiglio Nazionale delle Ricerche, Via P. Gobetti 101, 40129 Bologna, Italy
| | - Quinto G. Mulazzani
- ISOF, Consiglio Nazionale delle Ricerche, Via P. Gobetti 101, 40129 Bologna, Italy
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12
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Chatgilialoglu C, Bazzanini R, Jimenez LB, Miranda MA. (5'S)- and (5'R)-5',8-cyclo-2'-deoxyguanosine: mechanistic insights on the 2'-deoxyguanosin-5'-yl radical cyclization. Chem Res Toxicol 2007; 20:1820-4. [PMID: 17988100 DOI: 10.1021/tx700282x] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
The two diastereomeric forms (5'S) and (5'R) of 5',8-cyclo-2'-deoxyguanosine have been synthesized and fully characterized. They have been used as references for the investigation of gamma-irradiation of 2'-deoxyguanosine and photolysis of 8-bromo-2'-deoxyguanosine in aqueous solutions. The observed (5'R)/(5'S) ratio of 8:1 was obtained in both sets of experiments. The mechanism of the cyclization reaction is discussed in some detail, and the diastereomeric outcome is rationalized in terms of favorable hydrogen-bonded structures in the pro-(5'R) conformation.
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13
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Chatgilialoglu C, Caminal C, Altieri A, Vougioukalakis GC, Mulazzani QG, Gimisis T, Guerra M. Tautomerism in the guanyl radical. J Am Chem Soc 2007; 128:13796-805. [PMID: 17044708 DOI: 10.1021/ja062636h] [Citation(s) in RCA: 70] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Despite a few decades of intense study, a full description of tautomers of one-electron-oxidized guanine remains to be achieved. Here we show that two of these tautomers are produced by the protonation of an 8-haloguanine electron adduct. The rate constants for the reactions of hydrated electrons (e(aq)(-)) with a variety of 8-substituted guanine derivatives have been measured by a pulse radiolysis technique and correlated with both inductive and resonance components of the substituents. The fate of electron adducts was investigated by radiolytic methods coupled with product studies and addressed computationally by means of time-dependent DFT (TD-B3LYP/6-311G**//B1B95/6-31+G**) calculations. The reaction of e(aq)(-) with 8-haloguanosine or 8-halo-2'-deoxyguanosine produces the first observable transient species that decay unimolecularly (k = 1 x 10(5) s(-)(1) at 22 degrees C) to give the one-electron oxidized guanosine or 2'-deoxyguanosine. Theory suggests that the electron adducts of 8-bromoguanine derivatives protonated at C8 form a pi-complex, with the Br atom situated above the molecular plane, that is prompt to eject Br(-). The two short-lived intermediates, which show a substantial difference in their absorption spectra, are recognized to be the two purine tautomers (i.e., iminic 7 and aminic 3 forms). The spin density distributions of the two tautomers are quite different at the O6 and N10 positions, whereas they are very similar at the N3, C5, and C8 positions. The resonance structures of the two tautomers are discussed in some detail. B1B95/6-31+G calculations show also that the tautomerization from the iminic (7) to the aminic (3) arrangement is a water-assisted process.
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14
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Russo M, Jimenez LB, Mulazzani QG, D'Angelantonio M, Guerra M, Miranda MA, Chatgilialoglu C. Chemical radiation studies of 8-bromo-2'-deoxyinosine and 8-bromoinosine in aqueous solutions. Chemistry 2007; 12:7684-93. [PMID: 16823787 DOI: 10.1002/chem.200600040] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
The reactions of hydrated electrons (e(aq) (-)) with 8-bromo-2'-deoxyinosine (8) and 8-bromoinosine (12) have been investigated by radiolytic methods coupled with product studies and have been addressed computationally by means of BB1K-HMDFT calculations. Pulse radiolysis revealed that one-electron reductive cleavage of the C--Br bond gives the C8 radical 9 or 13 followed by a fast radical translocation to the sugar moiety. Selective generation of a C5' radical occurs in the 2'-deoxyribo derivative, whereas in the ribo analogue the reaction is partitioned between the C5' and C2' positions with similar rates. Both C5' radicals undergo cyclizations, 10-->11 and 14-->15, with rate constants of 1.4 x 10(5) and of 1.3 x 10(4) s(-1), respectively. The redox properties of radicals 10 and 11 have also been investigated. A synthetically useful photoreaction has also been developed as a one-pot procedure that allows the conversion of 8 to 5',8-cyclo-2'-deoxyinosine in a high yield and a diastereoisomeric ratio (5'R)/(5'S) of 4:1. The present results are compared with data previously obtained for 8-bromoadenine and 8-bromoguanine nucleosides. Theory suggests that the behavior of 8-bromopurine derivatives with respect to solvated electrons can be attributed to differences in the energy gap between the pi*- and sigma*-radical anions.
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Affiliation(s)
- Marialuisa Russo
- ISOF, Consiglio Nazionale delle Ricerche Via P. Gobetti 101, 40129 Bologna, Italy
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15
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Chatgilialoglu C, Caminal C, Guerra M, Mulazzani QG. Tautomers of one-electron-oxidized guanosine. Angew Chem Int Ed Engl 2006; 44:6030-2. [PMID: 16106467 DOI: 10.1002/anie.200501087] [Citation(s) in RCA: 55] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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16
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Manetto A, Breeger S, Chatgilialoglu C, Carell T. Komplexe Sequenzabhängigkeit beim Transport von Überschusselektronen durch DNA mit verschieden starken Acceptoren. Angew Chem Int Ed Engl 2006. [DOI: 10.1002/ange.200502551] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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17
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Wagenknecht HA. Electron transfer processes in DNA: mechanisms, biological relevance and applications in DNA analytics. Nat Prod Rep 2006; 23:973-1006. [PMID: 17119642 DOI: 10.1039/b504754b] [Citation(s) in RCA: 110] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
In principle, DNA-mediated charge transfer processes can be categorized as oxidative hole transfer and reductive electron transfer. With respect to the routes of DNA damage most of the past research has been focused on the investigation of oxidative hole transfer or transport. On the other hand, the transport or transfer of excess electrons has a large potential for biomedical applications, mainly for DNA chip technology.
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Affiliation(s)
- Hans-Achim Wagenknecht
- University of Regensburg, Institute for Organic Chemistry, D-93040, Regensburg, Germany.
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18
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Manetto A, Breeger S, Chatgilialoglu C, Carell T. Complex Sequence Dependence by Excess-Electron Transfer through DNA with Different Strength Electron Acceptors. Angew Chem Int Ed Engl 2006; 45:318-21. [PMID: 16315329 DOI: 10.1002/anie.200502551] [Citation(s) in RCA: 59] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- Antonio Manetto
- Department of Chemistry and Biochemistry, LMU Munich, Butenandtstrasse 5-13, 81377 Munich, Germany
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19
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Chatgilialoglu C, Caminal C, Guerra M, Mulazzani QG. Tautomers of One-Electron-Oxidized Guanosine. Angew Chem Int Ed Engl 2005. [DOI: 10.1002/ange.200501087] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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20
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de Champdore M, De Napoli L, Montesarchio D, Piccialli G, Caminal C, Mulazzani QG, Navacchia ML, Chatgilialoglu C. Excess electron transfer in G-quadruplex. Chem Commun (Camb) 2004:1756-7. [PMID: 15278171 DOI: 10.1039/b404473h] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The excess electron transfer in a G-quadruplex is successfully probed by using the reaction of hydrated electrons with quadruplex complex of pentamers and the 8-bromoguanine moieties as the detection system.
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Affiliation(s)
- Marcella de Champdore
- Dipartimento di Chimica Organica e Biochimica, Università di Napoli Federico II, Via Cynthia 4, 80126 Naples, Italy
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21
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Kimura T, Kawai K, Tojo S, Majima T. One-electron attachment reaction of B- and Z-DNA modified by 8-bromo-2'-deoxyguanosine. J Org Chem 2004; 69:1169-73. [PMID: 14961666 DOI: 10.1021/jo035194q] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The one-electron attachment reaction of 8-bromo-2'-deoxyguanosine ((Br)G) in DNA was studied by comparing that in B- and Z-DNA. Oligodeoxynucleotides (ODNs) modified by (Br)G were synthesized as Z-DNA in which the syn-conformation deoxyguanosine is stabilized by steric interference between the 8-bromo group of (Br)G and the sugar moiety. Debromination from the (Br)G-modified ODNs occurred from the one-electron attachment during the gamma-radiolysis. The structural dependence of B- and Z-DNA was observed for the one-electron attachment reaction. The conversion of (Br)G was higher in Z-DNA than in B-DNA. Because the solvent-accessible surface of the purine base in Z-DNA is greater than that in B-DNA, it is demonstrated that the reactivity of purine base C8 is enhanced in Z-DNA compared to that in B-DNA.
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Affiliation(s)
- Takumi Kimura
- The Institute of Scientific and Industrial Research (SANKEN), Osaka University, Mihogaoka 8-1, Ibaraki, Osaka 567-0047, Japan
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22
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Chatgilialoglu C, Guerra M, Mulazzani QG. Model studies of DNA C5' radicals. Selective generation and reactivity of 2'-deoxyadenosin-5'-yl radical. J Am Chem Soc 2003; 125:3839-48. [PMID: 12656617 DOI: 10.1021/ja029374d] [Citation(s) in RCA: 86] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The reaction of hydrated electrons (e(aq)(-)) with 8-bromo-2'-deoxyadenosine has been investigated by radiolytic methods coupled with product studies and addressed computationally by means of DFT-B3LYP calculations. Pulse radiolysis revealed that this reaction was complete in approximately 0.3 mus, and, at this time, no significant absorption was detected. The spectrum of a transient developed in 20 mus has an absorbance in the range 300-500 nm (epsilon(max) congruent with 9600 M(-1) cm(-1) at 360 nm), and it was assigned to aromatic aminyl radical 3. Computed vertical transitions (TD-UB3LYP/6-311+G) are in good agreement with the experimental observations. Radical 3 is obtained by the following reaction sequence: one-electron reductive cleavage of the C-Br bond that gives the C8 radical, a fast radical translocation from the C8 to C5' position, and an intramolecular attack of the C5' radical at the C8,N7 double bond of the adenine moiety. The rate constant for the cyclization is 1.6 x 10(5) s(-1). On the basis of the theoretical findings, the cyclization step is highly stereospecific. The rate constants for the reactions of C5' and aminyl 3 radicals with different oxidants were determined by pulse radiolysis methods. The respective rate constants for the reaction of 2'-deoxyadenosin-5'-yl radical with dioxygen, Fe(CN)(6)(3)(-), and MV(2+) in water at ambient temperature are 1.9 x 10(9), 4.2 x 10(9), and 2.2 x 10(8) M(-1) s(-1). The value for the reaction of aminyl radical 3 with Fe(CN)(6)(3-) is 8.3 x 10(8) M(-1) s(-1), whereas the reaction with dioxygen is reversible. Tailored experiments allowed the reaction mechanism to be defined in some detail. A synthetically useful radical cascade process has also been developed that allows in a one-pot procedure the conversion of 8-bromo-2'-deoxyadenosine to 5',8-cyclo-2'-deoxyadenosine in a diastereoisomeric ratio (5'R):(5'S) = 6:1 and in high yield, by reaction with hydrated electrons in the presence of K(4)Fe(CN)(6).
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23
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Papadantonakis GA, Tranter R, Brezinsky K, Yang Y, van Breemen RB, LeBreton PR. Low-Energy, Low-Yield Photoionization, and Production of 8-Oxo-2‘-deoxyguanosine and Guanine from 2‘-Deoxyguanosine. J Phys Chem B 2002. [DOI: 10.1021/jp020649l] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Affiliation(s)
- George A. Papadantonakis
- Department of Chemistry, University of Illinois at Chicago, Chicago, Illinois 60607, Department of Chemical Engineering, University of Illinois at Chicago, Chicago, Illinois 60607, and Department of Medicinal Chemistry and Pharmacognosy, College of Pharmacy, University of Illinois at Chicago, Chicago, Illinois 60612
| | - Robert Tranter
- Department of Chemistry, University of Illinois at Chicago, Chicago, Illinois 60607, Department of Chemical Engineering, University of Illinois at Chicago, Chicago, Illinois 60607, and Department of Medicinal Chemistry and Pharmacognosy, College of Pharmacy, University of Illinois at Chicago, Chicago, Illinois 60612
| | - Kenneth Brezinsky
- Department of Chemistry, University of Illinois at Chicago, Chicago, Illinois 60607, Department of Chemical Engineering, University of Illinois at Chicago, Chicago, Illinois 60607, and Department of Medicinal Chemistry and Pharmacognosy, College of Pharmacy, University of Illinois at Chicago, Chicago, Illinois 60612
| | - Yanan Yang
- Department of Chemistry, University of Illinois at Chicago, Chicago, Illinois 60607, Department of Chemical Engineering, University of Illinois at Chicago, Chicago, Illinois 60607, and Department of Medicinal Chemistry and Pharmacognosy, College of Pharmacy, University of Illinois at Chicago, Chicago, Illinois 60612
| | - Richard B. van Breemen
- Department of Chemistry, University of Illinois at Chicago, Chicago, Illinois 60607, Department of Chemical Engineering, University of Illinois at Chicago, Chicago, Illinois 60607, and Department of Medicinal Chemistry and Pharmacognosy, College of Pharmacy, University of Illinois at Chicago, Chicago, Illinois 60612
| | - Pierre R. LeBreton
- Department of Chemistry, University of Illinois at Chicago, Chicago, Illinois 60607, Department of Chemical Engineering, University of Illinois at Chicago, Chicago, Illinois 60607, and Department of Medicinal Chemistry and Pharmacognosy, College of Pharmacy, University of Illinois at Chicago, Chicago, Illinois 60612
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24
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Flyunt R, Bazzanini R, Chatgilialoglu C, Mulazzani QG. Fate of the 2‘-Deoxyadenosin-5‘-yl Radical under Anaerobic Conditions. J Am Chem Soc 2000. [DOI: 10.1021/ja9941577] [Citation(s) in RCA: 51] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Roman Flyunt
- I.Co.C.E.A. and F.R.A.E. Consiglio Nazionale delle Ricerche Via P. Gobetti 101, 40129 Bologna, Italy
| | - Rita Bazzanini
- I.Co.C.E.A. and F.R.A.E. Consiglio Nazionale delle Ricerche Via P. Gobetti 101, 40129 Bologna, Italy
| | | | - Quinto G. Mulazzani
- I.Co.C.E.A. and F.R.A.E. Consiglio Nazionale delle Ricerche Via P. Gobetti 101, 40129 Bologna, Italy
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