1
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Koi Y, Watanabe A, Kawasaki A, Ideo S, Matsutani N, Miyashita K, Shioi S, Tokunaga E, Shimokawa M, Nakatsu Y, Kuraoka I, Oda S. Mutation spectra of the BRCA1/2 genes in human breast and ovarian cancer and germline. ENVIRONMENTAL AND MOLECULAR MUTAGENESIS 2024; 65:179-186. [PMID: 38860553 DOI: 10.1002/em.22614] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/09/2024] [Revised: 05/20/2024] [Accepted: 05/23/2024] [Indexed: 06/12/2024]
Abstract
Annotating genomic sequence alterations is sometimes a difficult decision, particularly in missense variants with uncertain pathogenic significance and also in those presumed as germline pathogenic variants. We here suggest that mutation spectrum may also be useful for judging them. From the public databases, 982 BRCA1/1861 BRCA2 germline missense variants and 294 BRCA1/420 BRCA2 somatic missense variants were obtained. We then compared their mutation spectra, i.e., the frequencies of two transition- and four transversion-type mutations, in each category. Intriguingly, in BRCA1 variants, A:T to C:G transversion, which was relatively frequent in the germline, was extremely rare in somatic, particularly breast cancer, cells (p = .03). Conversely, A:T to T:A transversion was most infrequent in the germline, but not rare in somatic cells. Thus, BRCA1 variants with A:T to T:A transversion may be suspected as somatic, and those with A:T to C:G as being in the germline. These tendencies of mutation spectrum may also suggest the biological and chemical origins of the base alterations. On the other hand, unfortunately, variants of uncertain significance (VUS) were not distinguishable by mutation spectrum. Our findings warrant further and more detailed studies.
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Affiliation(s)
- Yumiko Koi
- Department of Breast Oncology, NHO Kyushu Cancer Center, Fukuoka, Japan
| | - Arisa Watanabe
- Department of Chemistry, Faculty of Science, Fukuoka University, Fukuoka, Japan
- Cancer Genetics Laboratory, Clinical Research Institute, NHO Kyushu Cancer Center, Fukuoka, Japan
| | - Akari Kawasaki
- Department of Chemistry, Faculty of Science, Fukuoka University, Fukuoka, Japan
- Cancer Genetics Laboratory, Clinical Research Institute, NHO Kyushu Cancer Center, Fukuoka, Japan
| | - Satomi Ideo
- Cancer Genetics and Genomics, NHO Kyushu Cancer Center, Fukuoka, Japan
| | - Nao Matsutani
- Cancer Genetics and Genomics, NHO Kyushu Cancer Center, Fukuoka, Japan
| | - Kaname Miyashita
- Cancer Genetics Laboratory, Clinical Research Institute, NHO Kyushu Cancer Center, Fukuoka, Japan
| | - Seijiro Shioi
- Cancer Genetics Laboratory, Clinical Research Institute, NHO Kyushu Cancer Center, Fukuoka, Japan
| | - Eriko Tokunaga
- Department of Breast Oncology, NHO Kyushu Cancer Center, Fukuoka, Japan
| | - Mototsugu Shimokawa
- Department of Biostatistics, Yamaguchi University Graduate School of Medicine, Ube, Japan
| | - Yoshimichi Nakatsu
- Cancer Genetics Laboratory, Clinical Research Institute, NHO Kyushu Cancer Center, Fukuoka, Japan
| | - Isao Kuraoka
- Department of Chemistry, Faculty of Science, Fukuoka University, Fukuoka, Japan
| | - Shinya Oda
- Cancer Genetics Laboratory, Clinical Research Institute, NHO Kyushu Cancer Center, Fukuoka, Japan
- Cancer Genetics and Genomics, NHO Kyushu Cancer Center, Fukuoka, Japan
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2
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Kruchinin AA, Kamzeeva PN, Zharkov DO, Aralov AV, Makarova AV. 8-Oxoadenine: A «New» Player of the Oxidative Stress in Mammals? Int J Mol Sci 2024; 25:1342. [PMID: 38279342 PMCID: PMC10816367 DOI: 10.3390/ijms25021342] [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: 11/30/2023] [Revised: 01/13/2024] [Accepted: 01/15/2024] [Indexed: 01/28/2024] Open
Abstract
Numerous studies have shown that oxidative modifications of guanine (7,8-dihydro-8-oxoguanine, 8-oxoG) can affect cellular functions. 7,8-Dihydro-8-oxoadenine (8-oxoA) is another abundant paradigmatic ambiguous nucleobase but findings reported on the mutagenicity of 8-oxoA in bacterial and eukaryotic cells are incomplete and contradictory. Although several genotoxic studies have demonstrated the mutagenic potential of 8-oxoA in eukaryotic cells, very little biochemical and bioinformatics data about the mechanism of 8-oxoA-induced mutagenesis are available. In this review, we discuss dual coding properties of 8-oxoA, summarize historical and recent genotoxicity and biochemical studies, and address the main protective cellular mechanisms of response to 8-oxoA. We also discuss the available structural data for 8-oxoA bypass by different DNA polymerases as well as the mechanisms of 8-oxoA recognition by DNA repair enzymes.
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Affiliation(s)
- Alexander A. Kruchinin
- Institute of Gene Biology, Russian Academy of Sciences, 34/5 Vavilova St., 119334 Moscow, Russia; (A.A.K.); (P.N.K.)
- National Research Center, Kurchatov Institute, Kurchatov sq. 2, 123182 Moscow, Russia
| | - Polina N. Kamzeeva
- Institute of Gene Biology, Russian Academy of Sciences, 34/5 Vavilova St., 119334 Moscow, Russia; (A.A.K.); (P.N.K.)
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Miklukho-Maklaya 16/10, 117997 Moscow, Russia;
| | - Dmitry O. Zharkov
- Department of Natural Sciences, Novosibirsk State University, 1 Pirogova St., 630090 Novosibirsk, Russia;
- Institute of Chemical Biology and Fundamental Medicine, Siberian Branch of the Russian Academy of Sciences, 8 Lavrentieva Ave., 630090 Novosibirsk, Russia
| | - Andrey V. Aralov
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Miklukho-Maklaya 16/10, 117997 Moscow, Russia;
| | - Alena V. Makarova
- Institute of Gene Biology, Russian Academy of Sciences, 34/5 Vavilova St., 119334 Moscow, Russia; (A.A.K.); (P.N.K.)
- National Research Center, Kurchatov Institute, Kurchatov sq. 2, 123182 Moscow, Russia
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3
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Kondhare D, Leonard P, Seela F. The Base Pairs of Isoguanine and 8-Aza-7-deazaisoguanine with 5-Methylisocytosine as Targets for DNA Functionalization. Bioconjug Chem 2023; 34:422-432. [PMID: 36735859 DOI: 10.1021/acs.bioconjchem.2c00584] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
The isoguanine-isocytosine base pair (isoG-isoC) represents an important expansion of the DNA coding system. The base pair is more stable than the canonical adenine-thymine or guanine-cytosine pairs. However, nothing is known on the functionalization of the noncanonical isoG-isoC pair at the isoguanine site. In this work, functionalization of the isoG-isoC and the isosteric base pair that contains 8-aza-7-deazaisoguanine in place of isoguanine is studied. Short ethynyl, more space demanding octadiynyl, and dendritic tripropargylamine residues attached to the isoG-isoC base pairs were introduced to oligonucleotides. 12-mer duplexes were formed by hybridization with single base pair modification. The use of the two modified nucleobases gave us the freedom to shift nucleobase substituents within the major groove of double helical DNA. Clickable side chains at position-7 stabilize the base pair, whereas 8-substituents reduce its stability strongly. The weak isoguanine-thymine or 8-aza-7-deazaisoguanine-thymine base pairs show a similar sensitivity to the position of nucleobase functionalization as base pair matches formed with 5-methylisocytosine. CD spectra of all modified duplexes display the typical shape of a B-DNA with only marginal changes. Fluorescent pyrene labeled DNA with long, short, and branched linkers was generated using click chemistry. Pyrene click adducts with long linkers are essential to maintain or to increase base pair stability. Labeled duplexes are more fluorescent than corresponding single strands. For the dendritic linker excimer emission was observed for single strands but only monomer emission in duplexes.
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Affiliation(s)
- Dasharath Kondhare
- Laboratory of Bioorganic Chemistry and Chemical Biology, Center for Nanotechnology, Heisenbergstrasse 11, 48149 Münster, Germany
| | - Peter Leonard
- Laboratory of Bioorganic Chemistry and Chemical Biology, Center for Nanotechnology, Heisenbergstrasse 11, 48149 Münster, Germany
| | - Frank Seela
- Laboratory of Bioorganic Chemistry and Chemical Biology, Center for Nanotechnology, Heisenbergstrasse 11, 48149 Münster, Germany.,Laboratorium für Organische und Bioorganische Chemie, Institut für Chemie neuer Materialien, Universität Osnabrück, Barbarastrasse 7, 49069 Osnabrück, Germany
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4
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Sharma M, Nair DT. Pfprex from
Plasmodium falciparum
can bypass oxidative stress‐induced DNA lesions. FEBS J 2022; 289:5218-5240. [DOI: 10.1111/febs.16414] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2021] [Revised: 01/13/2022] [Accepted: 02/25/2022] [Indexed: 12/24/2022]
Affiliation(s)
- Minakshi Sharma
- Regional Centre for Biotechnology Faridabad India
- Kalinga Institute of Industrial Technology Bhubaneshwar India
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5
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Caldero-Rodríguez NE, Crespo-Hernández CE. Excited state dynamics of 2'-deoxyisoguanosine and isoguanosine in aqueous solution. Phys Chem Chem Phys 2022; 24:6769-6781. [PMID: 35244114 DOI: 10.1039/d1cp05795b] [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
Photostability is thought to be an inherent property of nucleobases required to survive the extreme ultraviolet radiation conditions of the prebiotic era. Previous studies have shown that absorption of ultraviolet radiation by the canonical nucleosides results in ultrafast internal conversion to the ground state, demonstrating that these nucleosides efficiently dissipate the excess electronic energy to the environment. In recent years, studies on the photophysical and photochemical properties of nucleobase derivatives have revealed that chemical substitution influences the electronic relaxation pathways of purine and pyrimidine nucleobases. It has been suggested that amino or carbonyl substitution at the C6 position could increase the photostability of the purine derivatives more than the substitution at the C2 position. This investigation aims to elucidate the excited state dynamics of 2'-deoxyisoguanosine (dIsoGuo) and isoguanosine (IsoGuo) in aqueous solution at pH 7.4 and 1.4, which contain an amino group at the C6 position and a carbonyl group at the C2 position of the purine chromophore. The study of these derivatives is performed using absorption and emission spectroscopies, broadband transient absorption spectroscopy, and density functional and time-dependent density functional levels of theory. It is shown that the primary relaxation mechanism of dIsoGuo and IsoGuo involves nonradiative decay pathways, where the population decays from the S1(ππ*) state through internal conversion to the ground state via two relaxation pathways with lifetimes of hundreds of femtoseconds and less than 2 ps, making these purine nucleosides photostable in aqueous solution.
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6
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Ding T, Tang F, Ni G, Liu J, Zhao H, Chen Q. The development of isoguanosine: from discovery, synthesis, and modification to supramolecular structures and potential applications. RSC Adv 2020. [DOI: 10.1039/c9ra09427j] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
First systematical review of isoguanosine, an unnatural base, as an isomer of guanosine shows significant differences in diverse properties.
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Affiliation(s)
- Tingting Ding
- State Key Laboratory of Oral Diseases
- National Clinical Research Center for Oral Diseases
- Chinese Academy of Medical Sciences Research Unit of Oral Carcinogenesis and Management
- West China Hospital of Stomatology
- Sichuan University
| | - Fan Tang
- State Key Laboratory of Oral Diseases
- National Clinical Research Center for Oral Diseases
- Chinese Academy of Medical Sciences Research Unit of Oral Carcinogenesis and Management
- West China Hospital of Stomatology
- Sichuan University
| | - Guangcheng Ni
- State Key Laboratory of Oral Diseases
- National Clinical Research Center for Oral Diseases
- Chinese Academy of Medical Sciences Research Unit of Oral Carcinogenesis and Management
- West China Hospital of Stomatology
- Sichuan University
| | - Jiang Liu
- State Key Laboratory of Oral Diseases
- National Clinical Research Center for Oral Diseases
- Chinese Academy of Medical Sciences Research Unit of Oral Carcinogenesis and Management
- West China Hospital of Stomatology
- Sichuan University
| | - Hang Zhao
- State Key Laboratory of Oral Diseases
- National Clinical Research Center for Oral Diseases
- Chinese Academy of Medical Sciences Research Unit of Oral Carcinogenesis and Management
- West China Hospital of Stomatology
- Sichuan University
| | - Qianming Chen
- State Key Laboratory of Oral Diseases
- National Clinical Research Center for Oral Diseases
- Chinese Academy of Medical Sciences Research Unit of Oral Carcinogenesis and Management
- West China Hospital of Stomatology
- Sichuan University
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7
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Oxidatively induced DNA damage and its repair in cancer. MUTATION RESEARCH-REVIEWS IN MUTATION RESEARCH 2014; 763:212-45. [PMID: 25795122 DOI: 10.1016/j.mrrev.2014.11.002] [Citation(s) in RCA: 173] [Impact Index Per Article: 17.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/14/2014] [Revised: 11/03/2014] [Accepted: 11/04/2014] [Indexed: 12/28/2022]
Abstract
Oxidatively induced DNA damage is caused in living organisms by endogenous and exogenous reactive species. DNA lesions resulting from this type of damage are mutagenic and cytotoxic and, if not repaired, can cause genetic instability that may lead to disease processes including carcinogenesis. Living organisms possess DNA repair mechanisms that include a variety of pathways to repair multiple DNA lesions. Mutations and polymorphisms also occur in DNA repair genes adversely affecting DNA repair systems. Cancer tissues overexpress DNA repair proteins and thus develop greater DNA repair capacity than normal tissues. Increased DNA repair in tumors that removes DNA lesions before they become toxic is a major mechanism for development of resistance to therapy, affecting patient survival. Accumulated evidence suggests that DNA repair capacity may be a predictive biomarker for patient response to therapy. Thus, knowledge of DNA protein expressions in normal and cancerous tissues may help predict and guide development of treatments and yield the best therapeutic response. DNA repair proteins constitute targets for inhibitors to overcome the resistance of tumors to therapy. Inhibitors of DNA repair for combination therapy or as single agents for monotherapy may help selectively kill tumors, potentially leading to personalized therapy. Numerous inhibitors have been developed and are being tested in clinical trials. The efficacy of some inhibitors in therapy has been demonstrated in patients. Further development of inhibitors of DNA repair proteins is globally underway to help eradicate cancer.
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8
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Hitchcock DS, Fan H, Kim J, Vetting M, Hillerich B, Seidel RD, Almo SC, Shoichet BK, Sali A, Raushel FM. Structure-guided discovery of new deaminase enzymes. J Am Chem Soc 2013; 135:13927-33. [PMID: 23968233 DOI: 10.1021/ja4066078] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
A substantial challenge for genomic enzymology is the reliable annotation for proteins of unknown function. Described here is an interrogation of uncharacterized enzymes from the amidohydrolase superfamily using a structure-guided approach that integrates bioinformatics, computational biology, and molecular enzymology. Previously, Tm0936 from Thermotoga maritima was shown to catalyze the deamination of S-adenosylhomocysteine (SAH) to S-inosylhomocysteine (SIH). Homologues of Tm0936 homologues were identified, and substrate profiles were proposed by docking metabolites to modeled enzyme structures. These enzymes were predicted to deaminate analogues of adenosine including SAH, 5'-methylthioadenosine (MTA), adenosine (Ado), and 5'-deoxyadenosine (5'-dAdo). Fifteen of these proteins were purified to homogeneity, and the three-dimensional structures of three proteins were determined by X-ray diffraction methods. Enzyme assays supported the structure-based predictions and identified subgroups of enzymes with the capacity to deaminate various combinations of the adenosine analogues, including the first enzyme (Dvu1825) capable of deaminating 5'-dAdo. One subgroup of proteins, exemplified by Moth1224 from Moorella thermoacetica, deaminates guanine to xanthine, and another subgroup, exemplified by Avi5431 from Agrobacterium vitis S4, deaminates two oxidatively damaged forms of adenine: 2-oxoadenine and 8-oxoadenine. The sequence and structural basis of the observed substrate specificities were proposed, and the substrate profiles for 834 protein sequences were provisionally annotated. The results highlight the power of a multidisciplinary approach for annotating enzymes of unknown function.
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Affiliation(s)
- Daniel S Hitchcock
- Department of Biochemistry & Biophysics and ‡Department of Chemistry, Texas A&M University , College Station, Texas 77843, United States
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9
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Yu Y, Liu K, Zhao H, Song D. Mechanism of the deamination reaction of isoguanine: a theoretical investigation. J Phys Chem A 2013; 117:5715-25. [PMID: 23789717 DOI: 10.1021/jp4031738] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Mechanisms of the deamination reactions of isoguanine with H2O, OH(-), and OH(-)/H2O and of protonated isoguanine (isoGH(+)) with H2O have been investigated by theoretical calculations. Eight pathways, paths A-H, have been explored and the thermodynamic properties (ΔE, ΔH, and ΔG), activation energies, enthalpies, and Gibbs energies of activation were calculated for each reaction investigated. Compared with the deamination reaction of isoguanine or protonated isoguanine (isoGH(+)) with water, the deamination reaction of isoguanine with OH(-) shows a lower Gibbs energy of activation at the rate-determining step, indicating that the deamination reaction of isoguanine is favorably to take place for the deprotonated form isoG(-) with water. With the assistance of an extra water, the reaction of isoguanine with OH(-)/H2O, pathways F and H, are found to be the most feasible pathways in aqueous solution due to their lowest Gibbs energy of activation of 174.7 and 172.6 kJ mol(-1), respectively, at the B3LYP/6-311++G(d,p) level of theory.
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Affiliation(s)
- Youqing Yu
- Beijing National Laboratory for Molecular Sciences (BNLMS), State Key Laboratory of Molecular Reaction Dynamics, Institute of Chemistry, Chinese Academy of Sciences , Beijing 100190, China
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10
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Cheng Q, Gu J, Compaan KR, Schaefer HF. Isoguanine formation from adenine. Chemistry 2012; 18:4877-86. [PMID: 22411110 DOI: 10.1002/chem.201102415] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2011] [Indexed: 11/06/2022]
Abstract
Several possible mechanisms underlying isoguanine formation when OH radical attacks the C(2) position of adenine (A C 2) are investigated theoretically for the first time. Two steps are involved in this process. In the first step, one of two low-lying A C 2⋅⋅⋅OH reactant complexes is formed, leading to C(2)-H(2) bond cleavage. Between the two reactant complexes there is a small isomerization barrier, which lies well below separated adenine plus OH radical. The complex dissociates to free molecular hydrogen and an isoguanine tautomer (isoG 1 or isoG 2). The local and activation barriers for the two pathways are very similar. This evidence suggests that the two pathways are competitive. After dehydrogenation, there are two possible routes for the second step of the reaction. One is direct hydrogen transfer, via enol-keto tautomerization, which has high local barriers for both tautomers and is not favored. The other option is indirect hydrogen transfer involving microsolvation by one water molecule. The water lowers the reaction barrier by over 20 kcal mol(-1) , indicating that water-mediated hydrogen transfer is much more favorable. Both A+OH(⋅) →isoG+H(⋅) reactions are exothermic and spontaneous. Among four isoguanine tautomers, isoG 1 has the lowest energy. Our findings explain why only the N(1)H and O(2)H tautomers of isolated isoguanine and isoguanosine have been observed experimentally.
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Affiliation(s)
- Qianyi Cheng
- Center for Computational Quantum Chemistry, University of Georgia, Athens, GA 30602, USA
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11
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Hitchcock DS, Fedorov AA, Fedorov EV, Dangott LJ, Almo SC, Raushel FM. Rescue of the orphan enzyme isoguanine deaminase. Biochemistry 2011; 50:5555-7. [PMID: 21604715 DOI: 10.1021/bi200680y] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Cytosine deaminase (CDA) from Escherichia coli was shown to catalyze the deamination of isoguanine (2-oxoadenine) to xanthine. Isoguanine is an oxidation product of adenine in DNA that is mutagenic to the cell. The isoguanine deaminase activity in E. coli was partially purified by ammonium sulfate fractionation, gel filtration, and anion exchange chromatography. The active protein was identified by peptide mass fingerprint analysis as cytosine deaminase. The kinetic constants for the deamination of isoguanine at pH 7.7 are as follows: k(cat) = 49 s(-1), K(m) = 72 μM, and k(cat)/K(m) = 6.7 × 10(5) M(-1) s(-1). The kinetic constants for the deamination of cytosine are as follows: k(cat) = 45 s(-1), K(m) = 302 μM, and k(cat)/K(m) = 1.5 × 10(5) M(-1) s(-1). Under these reaction conditions, isoguanine is the better substrate for cytosine deaminase. The three-dimensional structure of CDA was determined with isoguanine in the active site.
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Affiliation(s)
- Daniel S Hitchcock
- Department of Biochemistry and Biophysics and Department of Chemistry, Texas A&M University, College Station, Texas 77843, USA
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12
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Hori M, Ishiguro C, Suzuki T, Nakagawa N, Nunoshiba T, Kuramitsu S, Yamamoto K, Kasai H, Harashima H, Kamiya H. UvrA and UvrB enhance mutations induced by oxidized deoxyribonucleotides. DNA Repair (Amst) 2007; 6:1786-93. [PMID: 17709303 DOI: 10.1016/j.dnarep.2007.06.013] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2006] [Revised: 06/28/2007] [Accepted: 06/29/2007] [Indexed: 10/22/2022]
Abstract
Oxidatively damaged DNA precursors (deoxyribonucleotides) are formed by reactive oxygen species. After the damaged DNA precursors are incorporated into DNA, they might be removed by DNA repair enzymes. In this study, to examine whether a nucleotide excision repair enzyme, Escherichia coli UvrABC, could suppress the mutations induced by oxidized deoxyribonucleotides in vivo, oxidized DNA precursors, 8-hydroxy-2'-deoxyguanosine 5'-triphosphate and 2-hydroxy-2'-deoxyadenosine 5'-triphosphate, were introduced into uvrA, uvrB, and uvrC E. coli strains, and mutations in the chromosomal rpoB gene were analyzed. Unexpectedly, these oxidized DNA precursors induced mutations only slightly in the uvrA and uvrB strains. In contrast, effect of the uvrC-deficiency was not observed. Next, mutT, mutT/uvrA, and mutT/uvrB E. coli strains were treated with H2O2, and the rpoB mutant frequencies were calculated. The frequency of the H2O2-induced mutations was increased in all of the strains tested; however, the increase was three- to four-fold lower in the mutT/uvrA and mutT/uvrB strains than in the mutT strain. Thus, UvrA and UvrB are involved in the enhancement, but not in the suppression, of the mutations induced by these oxidized deoxyribonucleotides. These results suggest a novel role for UvrA and UvrB in the processing of oxidative damage.
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Affiliation(s)
- Mika Hori
- Faculty of Pharmaceutical Sciences, Hokkaido University, Kita-12, Nishi-6, Kita-ku, Sapporo 060-0812, Japan
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13
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Crespan E, Hübscher U, Maga G. Error-free bypass of 2-hydroxyadenine by human DNA polymerase lambda with Proliferating Cell Nuclear Antigen and Replication Protein A in different sequence contexts. Nucleic Acids Res 2007; 35:5173-81. [PMID: 17666409 PMCID: PMC1976453 DOI: 10.1093/nar/gkm568] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
Abstract
1,2-dihydro-2-oxoadenine (2-OH-A), a common DNA lesion produced by reactive oxygen species, is a strong replicative block for several DNA polymerases (DNA pols). We have previously shown that various bases can be misincorporated opposite the 2-OH-A lesion and the type of mispairs varies with either the sequence context or the type of DNA pol tested. Here, we have analysed the ability of the human pol family X member DNA pol λ, to bypass the 2-OH-A lesion. DNA pol λ can perform error-free bypass of 2-OH-A when this lesion is located in a random sequence, whereas in a repeated sequence context, even though bypass was also largely error-free, misincorporation of dGMP could be observed. The fidelity of translesion synthesis of 2-OH-A in a repeated sequence by DNA pol λ was enhanced by the auxiliary proteins Proliferating Cell Nuclear Antigen (PCNA) and Replication Protein A (RP-A). We also found that the DNA pol λ active site residue tyrosine 505 determined the nucleotide selectivity opposite 2-OH-A. Our data show, for the first time, that the 2-OH-A lesion can be efficiently and faithfully bypassed by a human DNA pol λ in combination with PCNA and RP-A.
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Affiliation(s)
- Emmanuele Crespan
- Institute of Molecular Genetics IGM-CNR, via Abbiategrasso 207, I-27100 Pavia, Italy and Institute for Veterinary Biochemistry and Molecular Biology, University of Zürich-Irchel, Winterthurerstrasse 190, CH-8057 Zürich, Switzerland
| | - Ulrich Hübscher
- Institute of Molecular Genetics IGM-CNR, via Abbiategrasso 207, I-27100 Pavia, Italy and Institute for Veterinary Biochemistry and Molecular Biology, University of Zürich-Irchel, Winterthurerstrasse 190, CH-8057 Zürich, Switzerland
| | - Giovanni Maga
- Institute of Molecular Genetics IGM-CNR, via Abbiategrasso 207, I-27100 Pavia, Italy and Institute for Veterinary Biochemistry and Molecular Biology, University of Zürich-Irchel, Winterthurerstrasse 190, CH-8057 Zürich, Switzerland
- *To whom correspondence should be addressed.+39 0382546354+39 0382422286
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14
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Kamiya H. Mutations Induced by Oxidized DNA Precursors and Their Prevention by Nucleotide Pool Sanitization Enzymes. Genes Environ 2007. [DOI: 10.3123/jemsge.29.133] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
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15
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Satou K, Kasai H, Harashima H, Kamiya H. Induction of Substitution and Deletion Mutations by 2-Hydroxyadenine during Replication in a HeLa Extract. Genes Environ 2006. [DOI: 10.3123/jemsge.28.92] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
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16
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Seela F, Peng X, Li H. Base-pairing, tautomerism, and mismatch discrimination of 7-halogenated 7-deaza-2'-deoxyisoguanosine: oligonucleotide duplexes with parallel and antiparallel chain orientation. J Am Chem Soc 2005; 127:7739-51. [PMID: 15913364 DOI: 10.1021/ja0425785] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Oligonucleotides containing 2'-deoxyisoguanosine (1, iG(d)), 7-deaza-2'-deoxyisoguanosine (2, c(7)iG(d)), and its 7-halogenated derivatives 3 and 4 were synthesized on solid phase using the phosphoramidite building blocks 5-7. The hybridization properties of oligonucleotides were studied on duplexes with parallel and antiparallel chain orientation. It was found that the 7-halogenated nucleoside analogues 3 and 4 enhance the duplex stability significantly in both parallel (ps) and antiparallel (aps) DNA. Moreover, the halogenated nucleosides shift the tautomeric keto-enol equilibrium strongly toward the keto form, with K(TAUT) [keto]/[enol] approximately 10(4) coming close to that of 2'-deoxyguanosine (10(4)-10(5)), while the nonhalogenated 7-deaza-2'-deoxyisoguanosine 2 shows a K(TAUT) of around 2000 and the enol concentration of 1 is 10% in aqueous solution. Consequently, nucleosides 3 and 4 show a much better mismatch discrimination against dT than compound 1 or 2 in antiparallel as well as in parallel DNA. 3 and 4 are expected to increase the selectivity of base incorporation opposite to isoC(d) in the form of triphosphates or in the polymerase-catalyzed reaction in comparison to 1 or 2.
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Affiliation(s)
- Frank Seela
- Laboratorium für Organische und Bioorganische Chemie, Institut für Chemie, Universität Osnabrück, Barbarastrasse 7, D-49069 Osnabrück, Germany.
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17
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Kamiya H. Mutagenicities of 8-hydroxyguanine and 2-hydroxyadenine produced by reactive oxygen species. Biol Pharm Bull 2004; 27:475-9. [PMID: 15056850 DOI: 10.1248/bpb.27.475] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Oligodeoxyribonucleotides containing 8-hydroxyguanine and 2-hydroxyadenine, purine lesions produced in cells by reactive oxygen species, were synthesized and inserted into vector DNAs to introduce each lesion at a predetermined site. The manipulated DNAs were transfected into living cells, and the mutants induced by each DNA lesion were collected and analyzed. In addition, the mutations induced by damaged DNA precursors with the two oxidized purine bases were studied by the use of chemically synthesized nucleoside triphosphates. In this review article, the author summarizes the mutagenic potentials of the two oxidized purine bases, by focusing on experiments examined by the author and his collaborators.
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Affiliation(s)
- Hiroyuki Kamiya
- Graduate School of Pharmaceutical Sciences, Hokkaido University, Kita-12, Nishi-6, Kita-ku, Sapporo 060-0812, Japan.
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18
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Evans MD, Dizdaroglu M, Cooke MS. Oxidative DNA damage and disease: induction, repair and significance. MUTATION RESEARCH/REVIEWS IN MUTATION RESEARCH 2004; 567:1-61. [PMID: 15341901 DOI: 10.1016/j.mrrev.2003.11.001] [Citation(s) in RCA: 878] [Impact Index Per Article: 43.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/12/2003] [Revised: 11/12/2003] [Accepted: 11/12/2003] [Indexed: 04/08/2023]
Abstract
The generation of reactive oxygen species may be both beneficial to cells, performing a function in inter- and intracellular signalling, and detrimental, modifying cellular biomolecules, accumulation of which has been associated with numerous diseases. Of the molecules subject to oxidative modification, DNA has received the greatest attention, with biomarkers of exposure and effect closest to validation. Despite nearly a quarter of a century of study, and a large number of base- and sugar-derived DNA lesions having been identified, the majority of studies have focussed upon the guanine modification, 7,8-dihydro-8-oxo-2'-deoxyguanosine (8-OH-dG). For the most part, the biological significance of other lesions has not, as yet, been investigated. In contrast, the description and characterisation of enzyme systems responsible for repairing oxidative DNA base damage is growing rapidly, being the subject of intense study. However, there remain notable gaps in our knowledge of which repair proteins remove which lesions, plus, as more lesions identified, new processes/substrates need to be determined. There are many reports describing elevated levels of oxidatively modified DNA lesions, in various biological matrices, in a plethora of diseases; however, for the majority of these the association could merely be coincidental, and more detailed studies are required. Nevertheless, even based simply upon reports of studies investigating the potential role of 8-OH-dG in disease, the weight of evidence strongly suggests a link between such damage and the pathogenesis of disease. However, exact roles remain to be elucidated.
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Affiliation(s)
- Mark D Evans
- Oxidative Stress Group, Department of Clinical Biochemistry, University of Leicester, Leicester Royal Infirmary, University Hospitals of Leicester NHS Trust, LE2 7LX, UK
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19
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Abstract
The tautomeric properties of isoguanine (also named 2-oxoadenine or 2-hydroxyadenine) have been studied in the gas phase, in different pure solvents, and in the DNA environment using state of the art theoretical methods. Our results show that isoguanine constitutes an unique example of how tautomerism can be modulated by the environment. Compared to the tautomeric preference in the gas phase, both polar solvents and the DNA microenvironment dramatically change the intrinsic tautomeric properties of isoguanine. Tautomers which are important in physiological conditions are less than 1/10(5) of the total population of isoguanine in the gas phase. The impact of the present findings in the understanding of spontaneous mutations and in the design of new nucleobases with multiple recognition properties is discussed.
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Affiliation(s)
- José Ramón Blas
- Unitat de Modelització Molecular i Bioinformática, Institut de Recerca Biomédica, Parc Científic de Barcelona, Josep Samitier 1-5 Barcelona 08028, Spain
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20
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Minetti CASA, Remeta DP, Miller H, Gelfand CA, Plum GE, Grollman AP, Breslauer KJ. The thermodynamics of template-directed DNA synthesis: base insertion and extension enthalpies. Proc Natl Acad Sci U S A 2003; 100:14719-24. [PMID: 14623953 PMCID: PMC299778 DOI: 10.1073/pnas.2336142100] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2003] [Indexed: 11/18/2022] Open
Abstract
We used stopped-flow calorimetry to measure the overall enthalpy change associated with template-directed nucleotide insertion and DNA extension. Specifically, we used families of hairpin self-priming templates in conjunction with an exonuclease-free DNA polymerase to study primer extension by one or more dA or dT residues. Our results reveal exothermic heats between -9.8 and -16.0 kcal/bp for template-directed enzymatic polymerization. These extension enthalpies depend on the identity of the inserting base, the primer terminus, and/or the preceding base. Despite the complexity of the overall process, the sign, magnitude, and sequence dependence of these insertion and extension enthalpies are consistent with nearest-neighbor data derived from DNA melting studies. We recognize that the overall process studied here involves contributions from a multitude of events, including dNTP to dNMP hydrolysis, phosphodiester bond formation, and enzyme conformational changes. It is therefore noteworthy that the overall enthalpic driving force per base pair is of a magnitude similar to that expected for addition of one base pair or base stack per insertion event, rather than that associated with the rupture and/or formation of covalent bonds, as occurs during this catalytic process. Our data suggest a constant sequence-independent background of compensating enthalpic contributions to the overall process of DNA synthesis, with discrimination expressed by differences in noncovalent interactions at the template-primer level. Such enthalpic discrimination underscores a model in which complex biological events are regulated by relatively modest energy balances involving weak interactions, thereby allowing subtle mechanisms of regulation.
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Affiliation(s)
- Conceição A S A Minetti
- Department of Chemistry and Chemical Biology, Rutgers, The State University of New Jersey, 610 Taylor Road, Piscataway, NJ 08854, USA
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21
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Rogstad KN, Jang YH, Sowers LC, Goddard WA. First Principles Calculations of the pKa Values and Tautomers of Isoguanine and Xanthine. Chem Res Toxicol 2003; 16:1455-62. [PMID: 14615972 DOI: 10.1021/tx034068e] [Citation(s) in RCA: 68] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The accurate replication of DNA requires the formation of complementary hydrogen bonds between a template base and the base moiety of an incoming deoxynucleotide-5'-triphosphate. Recent structural studies suggest that some DNA polymerases contribute additional constraints by interrogating the minor groove face of the incoming and template bases. Therefore, the hydrogen bond-donating or -accepting properties of the base pairing as well as minor groove faces of the bases could be important determinants of correct base selection. In this paper, we investigate two purines that could arise by endogenous damage of the normal DNA bases: isoguanine (which can be generated by the oxidation of adenine) and xanthine (which can be generated by the deamination of guanine). In both cases, the potential exists for the placement of a proton in the N3 position, converting the N3 position from a hydrogen bond acceptor to a donor. In this paper, we use first principles quantum mechanical methods (density functional theory using the B3LYP functional and the 6-31G++Gbasis set) to predict the ionization and tautomeric equilibria of both isoguanine and xanthine in the gas phase and aqueous solution. For isoguanine, we find that the N1H and N3H neutral tautomeric forms are about equally populated in aqueous solution, while the enol tauotomers are predominant in the gas phase. In contrast, we find that xanthine displays essentially no tautomeric shifts in aqueous solution but is nearly equally populated by both an anionic and a neutral form at physiological pH. To obtain these results, we carried out an extensive examination of the tautomeric and ionic configurations for both xanthine and isoguanine in solution and in the gas phase. The potential hydrogen-bonding characteristics of these damaged purines may be used to test predictions of the important components of base selection by different DNA polymerases during DNA replication.
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Affiliation(s)
- Katherine Noyes Rogstad
- Department of Biochemistry and Microbiology, Loma Linda University School of Medicine, Loma Linda, California 92350, USA
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22
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Maciejewska AM, Lichota KD, Kuśmierek JT. Neighbouring bases in template influence base-pairing of isoguanine. Biochem J 2003; 369:611-8. [PMID: 12387728 PMCID: PMC1223114 DOI: 10.1042/bj20020922] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2002] [Revised: 09/18/2002] [Accepted: 10/21/2002] [Indexed: 11/17/2022]
Abstract
Assuming that the efficiency of the incorporation of 5-methyl-2'-deoxyisocytosine-5' triphosphate (dMiCTP) and dTTP opposite isoguanine (iG) is a measure of the proportion of the keto and enol tautomers of iG in the Thermus aquaticus DNA polymerase active centre, we studied the influence of temperature and iG-neighbouring bases in the template on base-pairing of iG. On the basis of experiments with four sequences (3'-TXT-5', 3'-GXG-5', 3'-CXC-5', 3'-CXT-5', where X=iG) at 37, 50, 65 and 80 degrees C, we found that 3'-neighbours decrease the fraction of the keto tautomer in the order C>G>or=T, whereas temperature apparently does not influence the tautomeric equilibrium of iG. The variability of the ratio of incorporation of dMiCTP versus dTTP (5-20) primarily reflects the variability of K (m) values, since V (max) values are roughly similar, which indicates that the iG.MiC and iG.T pairs fit the polymerase active centre equally well. The altering of the base-pairing of iG by sequence context is discussed in relation to tautomerism and miscoding of this oxidized adenine derivative. A key derivative for preparation oligodeoxynucleotides, O (2)-diphenylcarbamoyl- N (6)-[(dimethylamino)ethylidene]-2'-deoxyisoguanosine, is extremely labile (t (1/2)=3.5 min) in 3% trichloroacetic acid/dichloromethane, i.e. under the conditions of automated DNA synthesis, which results in low yield and length heterogeneity of templates.
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Affiliation(s)
- Agnieszka M Maciejewska
- Department of Molecular Biology, Institute of Biochemistry and Biophysics, Polish Academy of Sciences, 5A Pawińskiego Str., 02 106 Warsaw, Poland
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23
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Kamiya H. Mutagenic potentials of damaged nucleic acids produced by reactive oxygen/nitrogen species: approaches using synthetic oligonucleotides and nucleotides: survey and summary. Nucleic Acids Res 2003; 31:517-31. [PMID: 12527759 PMCID: PMC140503 DOI: 10.1093/nar/gkg137] [Citation(s) in RCA: 211] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
DNA and DNA precursors (deoxyribonucleotides) suffer damage by reactive oxygen/nitrogen species. They are important mutagens for organisms, due to their endogenous formation. Damaged DNA and nucleotides cause alterations of the genetic information by the mispairing properties of the damaged bases, such as 8-hydroxyguanine (7,8-dihydro-8-oxoguanine) and 2-hydroxyadenine. Here, the author reviews the mutagenic potentials of damaged bases in DNA and of damaged DNA precursors formed by reactive oxygen/nitrogen species, focusing on the results obtained with synthetic oligonucleotides and 2'-deoxyribonucleoside 5'-triphosphates.
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Affiliation(s)
- Hiroyuki Kamiya
- Graduate School of Pharmaceutical Sciences, Hokkaido University, Kita-12, Nishi-6, Kita-ku, Sapporo 060-0812, Japan.
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24
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Abstract
The principal oxidized cytosine bases, uracil glycol, 5-hydroxycytosine, and 5-hydroxyuracil, are readily bypassed, miscode, and are thus important premutagenic lesions. Similarly the principal oxidation product of guanine, 8-oxoguanine, miscodes with A and is a premutagenic lesion. Most of the thymine and adenine products that retain their ring structure primarily pair with their cognate bases and are not potent premutagenic lesions. Although thymine glycol pairs with its cognate base and is not mutagenic it significantly distorts the DNA molecule and is a lethal lesion. Ring fragmentation, ring contraction, and ring open products of both pyrimidines and purines block DNA polymerases and are potentially lethal lesions. Although these breakdown products have the potential to mispair during translesion synthesis, the mutational spectra of prokaryotic mutants defective in the pyrimidine-specific and/or purine-specific DNA glycosylases do not reflect that expected of the breakdown products. Taken together, the data suggest that the principal biological consequences of endogenously produced and unrepaired free radical-damaged DNA bases are mutations.
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Affiliation(s)
- Susan S Wallace
- Department of Microbiology and Molecular Genetics, The Markey Center for Molecular Genetics, The University of Vermont, Burlington, VT 05405-0068, USA.
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25
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Kawakami J, Kamiya H, Yasuda K, Fujiki H, Kasai H, Sugimoto N. Thermodynamic stability of base pairs between 2-hydroxyadenine and incoming nucleotides as a determinant of nucleotide incorporation specificity during replication. Nucleic Acids Res 2001; 29:3289-96. [PMID: 11504865 PMCID: PMC55858 DOI: 10.1093/nar/29.16.3289] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
We investigated the thermodynamic stability of double-stranded DNAs with an oxidative DNA lesion, 2-hydroxyadenine (2-OH-Ade), in two different sequence contexts (5'-GA*C-3' and 5'-TA*A-3', A* represents 2-OH-Ade). When an A*-N pair (N, any nucleotide base) was located in the center of a duplex, the thermodynamic stabilities of the duplexes were similar for all the natural bases except A (N = T, C and G). On the other hand, for the duplexes with the A*-N pair at the end, which mimic the nucleotide incorporation step, the stabilities of the duplexes were dependent on their sequence. The order of stability is T > G > C >> A in the 5'-GA*C-3' sequences and T > A > C > G in the 5'-TA*A-3' sequences. Because T/G/C and T/A are nucleotides incorporated opposite to 2-OH-Ade in the 5'-GA*C-3' and 5'-TA*A-3' sequences, respectively, these results agree with the tendency of mutagenic misincorporation of the nucleotides opposite to 2-OH-Ade in vitro. Thus, the thermodynamic stability of the A*-N base pair may be an important factor for the mutation spectra of 2-OH-Ade.
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Affiliation(s)
- J Kawakami
- Department of Chemistry, Faculty of Science and Engineering, Konan University, 8-9-1 Okamoto, Higashinada-ku, Kobe 658-8501, Japan
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26
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Kamiya H, Kasai H. 2-Hydroxy-dATP is incorporated opposite G by Escherichia coli DNA polymerase III resulting in high mutagenicity. Nucleic Acids Res 2000; 28:1640-6. [PMID: 10710431 PMCID: PMC102799 DOI: 10.1093/nar/28.7.1640] [Citation(s) in RCA: 45] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
Abstract
Four kinds of oxidatively damaged DNA precursors, 8-hydroxydeoxyguanosine 5'-triphosphate (8-OH-dGTP), 2-hydroxydeoxyadenosine 5'-triphosphate (2-OH-dATP), 5-hydroxydeoxycytidine 5'-triphosphate (5-OH-dCTP) and 5-formyldeoxyuridine 5'-triphosphate (5-CHO-dUTP), were employed in in vitro gap-filling reactions of the supF gene conducted by the Escherichia coli DNA polymerase III holoenzyme, and these treated DNAs were transfected into various E.coli strains. When the manipulated DNAs were transfected into the repair-proficient strain, supF mutants were obtained much more frequently by the purine nucleotides than by the pyrimidine nucleotides (2-OH-dATP > 8-OH-dGTP >> 5-OH-dCTP approximately 5-CHO-dUTP). This result is in contrast to our previous observation that these four oxidatively damaged nucleotides induce chromosomal gene mutations with similar frequencies when incorporated directly into E.coli. 2-OH-dATP elicited G-->T transversions, indicating the formation of G*2-OH-dATP pairs. These results demonstrate that 2-OH-dATP was highly mutagenic in this assay system containing the in vitro DNA synthesis by the E.coli replicative DNA polymerase, in addition to in the in vivo assay system reported previously. Slight increases in the mutant frequencies were observed when alkA (for 8-OH-dGTP and 2-OH-dATP) and mutY (for 2-OH-dATP) strains were used as hosts. This is the first report that clearly shows the formation of G*2-OH-dATP pairs.
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Affiliation(s)
- H Kamiya
- Department of Environmental Oncology, University of Occupational and Environmental Health, 1-1 Iseigaoka, Yahatanishi-ku, Kitakyushu 807-8555, Japan
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27
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Graziewicz MA, Zastawny TH, Oliński R, Speina E, Siedlecki J, Tudek B. Fapyadenine is a moderately efficient chain terminator for prokaryotic DNA polymerases. Free Radic Biol Med 2000; 28:75-83. [PMID: 10656293 DOI: 10.1016/s0891-5849(99)00208-7] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Abstract
Hypoxanthine¿xanthine oxidase¿Fe3+¿ethylenediaminetetraacetate (EDTA) was used to modify ss M13 mp18 phage DNA. The dominant base modifications found by GC/IDMS-SIM were FapyGua, FapyAde, 8-hydroxyguanine, and thymine glycol. Analysis of in vitro DNA synthesis on oxidatively modified template by three DNA polymerases revealed that T7 DNA polymerase and Klenow fragment of polymerase I from Escherichia coli were blocked mainly by oxidized pyrimidines in the template whereas some purines that were easily bypassed by the prokaryotic polymerases constituted a block for DNA polymerase beta from calf thymus. DNA synthesis by T7 polymerase on poly(dA) template, where FapyAde content increased 16-fold on oxidation, yielded a final product with a discrete ladder of premature termination bands. When DNA synthesis was performed on template from which FapyAde, FapyGua, and 8OHGua were excised by the Fpg protein new chain terminations at adenine and guanine sites appeared or existing ones were enhanced. This suggests that FapyAde, when present in DNA, is a moderately toxic lesion. Its ability to arrest DNA synthesis depends on the sequence context and DNA polymerase. FapyGua might possess similar properties.
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Affiliation(s)
- M A Graziewicz
- Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Warsaw
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28
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Cysewski P. Structure and properties of hydroxyl radical modified nucleic acid components: pairing properties of 2-hydroxyadenine and 8-oxoadenine. ACTA ACUST UNITED AC 1999. [DOI: 10.1016/s0166-1280(98)00341-8] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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29
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Abalea V, Cillard J, Dubos MP, Sergent O, Cillard P, Morel I. Repair of iron-induced DNA oxidation by the flavonoid myricetin in primary rat hepatocyte cultures. Free Radic Biol Med 1999; 26:1457-66. [PMID: 10401609 DOI: 10.1016/s0891-5849(99)00010-6] [Citation(s) in RCA: 68] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
Oxidative DNA damage and its repair in primary rat hepatocyte cultures was investigated following 4 h of incubation with the toxic iron chelate, ferric nitrilotriacetate (Fe-NTA), in the presence or absence of the potent protective flavonoid myricetin (25-50-100 microM). Seven DNA base oxidation products were quantified in DNA extracts by gas chromatography-mass spectrometry (GC-MS) in selected ion monitoring mode. Concomitantly, DNA repair capacity of hepatocytes was estimated by the release of oxidized-base products into culture media, using the same GC-MS method. A genotoxic effect of Fe-NTA (100 microM) in hepatocytes was evidenced by a severe increase in DNA oxidation over basal levels, with accumulation in cellular DNA of five oxidation products derived from both purines and pyrimidines. This prooxidant effect of iron was also noted by an induction of lipid peroxidation, estimated by free malondialdehyde production. Addition of increasing concentrations of myricetin (25-50-100 microM) simultaneously with iron prevented both lipid peroxidation and accumulation of oxidation products in DNA. Moreover, as an activation of DNA repair pathways, myricetin stimulated the release of DNA oxidation bases into culture media, especially of purine-derived oxidation products. This removal of highly mutagenic oxidation products from DNA of hepatocytes might correspond to an activation of DNA excision-repair enzymes by myricetin. This was verified by RNA blot analysis of DNA polymerase beta gene expression which was induced by myricetin in a dose-dependent manner. This represented a novel and original mechanism of cytoprotection by myricetin against iron-induced genotoxicity via stimulation of DNA repair processes. Since iron-induced DNA damage and inefficient repair in hepatocytes could be related to genotoxicity and most probably to hepatocarcinogenesis, modulation of these processes in vitro by myricetin might be relevant in further prevention of liver cancer derived from iron overload pathologies.
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Affiliation(s)
- V Abalea
- Laboratoire de Biologie Cellulaire et Végétale, UFR des Sciences Pharmaceutiques et Biologiques, Rennes, France
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30
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Graziewicz MA, Zastawny TH, Oliński R, Tudek B. SOS-dependent A-->G transitions induced by hydroxyl radical generating system hypoxanthine/xanthine oxidase/Fe3+/EDTA are accompanied by the increase of Fapy-adenine content in M13 mp18 phage DNA. Mutat Res 1999; 434:41-52. [PMID: 10377947 DOI: 10.1016/s0921-8777(99)00012-9] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Gas chromatography/isotope dilution-mass spectrometry with selected ion monitoring (GC/IDMS-SIM) was used to measure oxidised bases in hypoxanthine/xanthine oxidase/Fe3+/EDTA modified ss M13 mp18 phage DNA. A dose-dependent increase of oxidised bases content in DNA was observed with the biggest augmentation of FapyGua, thymine glycol and FapyAde. The amount of 8-OH-Gua was relatively high both in non-oxidised and oxidised DNA, and increased to the same extent as FapyAde and ThyGly. DNA oxidation caused a dramatic decrease in phage survival after transfection to E. coli. Survival was improved 2.8-fold after induction of the SOS system by UV irradiation of bacteria and mutation frequency of the lacZ gene in SOS conditions increased 7-fold over that in non-irradiated bacteria. Spectrum of mutations was different from those reported previously and mutations were distributed rather randomly within M13 lacZ sequence, which was in contrast to previous findings, where with non-chelated metal ions other types of mutations were found in several clusters. Thus, conditions of DNA oxidation and accessibility of metal ions for DNA bases might be important factors for generating different DNA damages and mutations. Major base substitutions found both in SOS-induced and non-induced E. coli but with higher mutation frequency in SOS-induced cells were C-->A (approximately 20-fold increase in SOS-conditions), G-->A (9-fold increase) and G-->C (4.5-fold increase). Very few G-->T transitions were found. A particularly large group of A-->G transitions appeared only in SOS-induced bacteria and was accompanied by augmentation of FapyAde content in the phage DNA with undetectable 2-OH-Ade. It is then possible that imidazole ring-opened adenine mimics guanine during DNA replication and pairs with cytosine yielding A-->G transitions in SOS-induced bacteria.
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Affiliation(s)
- M A Graziewicz
- Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Warsaw, Poland
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31
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Yang XL, Sugiyama H, Ikeda S, Saito I, Wang AH. Structural studies of a stable parallel-stranded DNA duplex incorporating isoguanine:cytosine and isocytosine:guanine basepairs by nuclear magnetic resonance spectroscopy. Biophys J 1998; 75:1163-71. [PMID: 9726918 PMCID: PMC1299791 DOI: 10.1016/s0006-3495(98)74035-4] [Citation(s) in RCA: 46] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
Isoguanine (2-hydroxyladenine) is a product of oxidative damage to DNA and has been shown to cause mutation. It is also a potent inducer of parallel-stranded DNA duplex structure. The structure of the parallel-stranded DNA duplex (PS-duplex) 5'-d(TiGiCAiCiGiGAiCT) + 5'-d(ACGTGCCTGA), containing the isoguanine (iG) and 5-methyl-isocytosine (iC) bases, has been determined by NMR refinement. All imino protons associated with the iG:C, G:iC, and A:T (except the two terminal A:T) basepairs are observed at 2 degrees C, consistent with the formation of a stable duplex suggested by the earlier Tm measurements [Sugiyama, H., S. Ikeda, and I. Saito. 1996. J. Am. Chem. Soc. 118:9994-9995]. All basepairs are in the reverse Watson-Crick configuration. The structural characteristics of the refined PS-duplex are different from those of B-DNA. The PS duplex has two grooves with similar width (7.0 A) and depth (7.7 A), in contrast to the two distinct grooves (major groove width 11.7 A, depth 8.5 A, and minor groove width 5.7 A, depth 7.5 A) of B-DNA. The resonances of the amino protons of iG and C are clearly resolved and observable, but those of the G and iC are very broad and difficult to observe. Several intercalators with different complexities, including ethidium, daunorubicin, and nogalamycin, have been used to probe the flexibility of the backbone of the (iG, iC)-containing PS-duplex. All of them produce drug-induced UV/vis spectra identical to their respective spectra when bound to B-DNA, suggesting that those drugs bind to the (iG, iC)-containing PS-duplex using similar intercalation processes. The results may be useful in the design of intercalator-conjugated oligonucleotides for antisense applications. The study presented in this paper augments our understanding of a growing number of parallel-stranded DNA structures, including the G-quartet, the i-motif, and the unusual homo basepaired parallel-stranded double helix. Their possible relevance is discussed.
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Affiliation(s)
- X L Yang
- Department of Cell and Structural Biology, University of Illinois, Urbana-Champaign 61801, USA
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Tsurudome Y, Hirano T, Kamiya H, Yamaguchi R, Asami S, Itoh H, Kasai H. 2-Hydroxyadenine, a mutagenic form of oxidative DNA damage, is not repaired by a glycosylase type mechanism in rat organs. Mutat Res 1998; 408:121-7. [PMID: 9739814 DOI: 10.1016/s0921-8777(98)00025-1] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Oxygen radicals are known to play a role in causing cellular DNA damage, which is involved in carcinogenesis. 8-Hydroxyguanine (8-OH-Gua) is a major form of oxidative DNA damage and is known as a useful marker of DNA oxidation. Recently, we found another type of oxidative DNA damage, 2-hydroxyadenine (2-OH-Ade), which has a mutation frequency comparable to that of 8-OH-Gua. We compared the repair activities for two types of oxidative DNA damage, 8-OH-Gua and 2-OH-Ade, in 7-week-old male Sprague-Dawley (SD) rat organs. The repair activities were measured by an endonuclease nicking assay using 22 mer [32P]-end-labeled double-stranded DNA substrates, which contained either 8-OH-Gua (opposite C) or 2-OH-Ade (opposite T or C). In all of the SD rat organs we studied, the nicking activity for 2-OH-Ade was not detected, while that for 8-OH-Gua was clearly detected with the same conditions. Moreover, the 2-OH-Ade nicking activity was not induced in Wistar rat kidney extracts prepared after ferric nitrilotriacetate (Fe-NTA) treatment, which is known to increase 8-OH-Gua repair activity. These results suggest that 2-OH-Ade might not be repaired by the glycosylase type mechanism in mammalian cells.
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Affiliation(s)
- Y Tsurudome
- Department of Environmental Oncology, University of Occupational and Environmental Health, Kitakyushu, Japan
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33
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Robinson H, Gao YG, Bauer C, Roberts C, Switzer C, Wang AH. 2'-Deoxyisoguanosine adopts more than one tautomer to form base pairs with thymidine observed by high-resolution crystal structure analysis. Biochemistry 1998; 37:10897-905. [PMID: 9692982 DOI: 10.1021/bi980818l] [Citation(s) in RCA: 78] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
The questions of whether different tautomeric forms of nucleic acid bases exist to any significant extent in DNA, or what their possible roles in mutation may be, are under intense scrutiny. 2'-Deoxyisoguanosine (iG) has been suggested to have a propensity to adopt the enol form. Isoguanine (also called 2-hydroxyadenine) can be found in oxidatively damaged DNA generated from treating DNA with a Fenton-type reactive oxygen-generating system and is known to cause mutation. We have analyzed the three-dimensional structure of the DNA dodecamer d(CGC[iG]AATTTGCG) (denoted iG-DODE) by X-ray crystallography and NMR. The crystal structure of the iG-DODE complexed with the minor groove binder Hoechst 33342, refined to 1.4 A resolution, showed that the two independent iG.T base pairs in the dodecamer duplex adopt different (one in Watson-Crick and the other in wobble) conformations. The high-resolution nature of the structure also affords unprecedented clear information about the conformation and interactions of the Hoechst drug. The Hoechst 33342 binds in the narrow minor groove at the iGAATT site, with the N-methylpiperazine ring near the iG4.T21 base pair. Three hydrogen bonds are found between the NH of the Hoechst ligand and T-O2 DNA atoms. In solution, the two iG.T base pairs in iG-DODE predominantly are in the wobble form at 2 degreesC. At higher temperatures, another duplex form (likely involving the enol form of iG) is in slow exchange with the keto form and becomes significantly populated, reaching approximately 40% at 40 degreesC. Our data support the conclusion that iG pairs with T in a Watson-Crick configuration to a significant extent at physiological temperature (37 degreesC), which may explain the facile incorporation rate of T across from an iG during in vitro DNA replication.
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Affiliation(s)
- H Robinson
- Department of Cell and Structural Biology, University of Illinois at Urbana-Champaign 61801, USA
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34
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Arashidani K, Iwamoto-Tanaka N, Muraoka M, Kasai H. Genotoxicity of ribo- and deoxyribonucleosides of 8-hydroxyguanine, 5-hydroxycytosine, and 2-hydroxyadenine: induction of SCE in human lymphocytes and mutagenicity in Salmonella typhimurium TA 100. Mutat Res 1998; 403:223-7. [PMID: 9726022 DOI: 10.1016/s0027-5107(98)00086-4] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
The induction of SCE by ribo- and deoxyribonucleosides of 8-hydroxyguanine, 5-hydroxycytosine, and 2-hydroxyadenine was tested using human peripheral blood lymphocytes. All of these compounds caused an increase in SCE frequency. The potency of SCE induction was as follows: 5-OH-C, 5-OH-dC > 8.OH-G > 8-OH-dG > 2-OH-A, 2-OH-dA. These results suggest that the oxidized nucleosides are incorporated into DNA with different efficiencies (or are repaired with different efficiencies) and exhibit genotoxicity in human blood cells. Ribo- and deoxyribo-derivatives of 5-OH-Cyt and 2-OH-Ade also showed mutagenic activity in Salmonella typhimurium TA 100.
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Affiliation(s)
- K Arashidani
- Department of Environmental Management, School of Health Sciences, University of Occupational and Environmental Health Japan, Kitakyushu, Japan
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35
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Wang D, Kreutzer DA, Essigmann JM. Mutagenicity and repair of oxidative DNA damage: insights from studies using defined lesions. Mutat Res 1998; 400:99-115. [PMID: 9685598 DOI: 10.1016/s0027-5107(98)00066-9] [Citation(s) in RCA: 369] [Impact Index Per Article: 14.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Oxidative DNA damage has been implicated in mutagenesis, carcinogenesis and aging. Endogenous cellular processes such as aerobic metabolism generate reactive oxygen species (ROS) that interact with DNA to form dozens of DNA lesions. If unrepaired, these lesions can exert a number of deleterious effects including the induction of mutations. In an effort to understand the genetic consequences of cellular oxidative damage, many laboratories have determined the patterns of mutations generated by the interaction of ROS with DNA. Compilation of these mutational spectra has revealed that GC-->AT transitions and GC-->TA transversions are the most commonly observed mutations resulting from oxidative damage to DNA. Since mutational spectra convey only the end result of a complex cascade of events, which includes formation of multiple adducts, repair processing, and polymerase errors, it is difficult if not impossible to assess the mutational specificity of individual DNA lesions directly from these spectra. This problem is especially complicated in the case of oxidative DNA damage owing to the multiplicity of lesions formed by a single damaging agent. The task of assigning specific features of mutational spectra to individual DNA lesions has been made possible with the advent of a technology to analyze the mutational properties of single defined adducts, in vitro and in vivo. At the same time, parallel progress in the discovery and cloning of repair enzymes has advanced understanding of the biochemical mechanisms by which cells excise DNA damage. This combination of tools has brought our understanding of DNA lesions to a new level of sophistication. In this review, we summarize the known properties of individual oxidative lesions in terms of their structure, mutagenicity and repairability.
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Affiliation(s)
- D Wang
- Division of Toxicology and Department of Chemistry, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
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36
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Inoue M, Kamiya H, Fujikawa K, Ootsuyama Y, Murata-Kamiya N, Osaki T, Yasumoto K, Kasai H. Induction of chromosomal gene mutations in Escherichia coli by direct incorporation of oxidatively damaged nucleotides. New evaluation method for mutagenesis by damaged DNA precursors in vivo. J Biol Chem 1998; 273:11069-74. [PMID: 9556591 DOI: 10.1074/jbc.273.18.11069] [Citation(s) in RCA: 93] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
Abstract
We have developed a new strategy for the evaluation of the mutagenicity of a damaged DNA precursor (deoxyribonucleoside 5'-triphosphate) in Escherichia coli. 8-Hydroxydeoxyguanosine triphosphate (8-OH-dGTP) and 2-hydroxydeoxyadenosine triphosphate (2-OH-dATP) were chosen for this study because they appear to be formed abundantly by reactive oxygen species in cells. We introduced the oxidatively damaged nucleotides into competent E. coli and selected mutants of the chromosomal lacI gene. Both damaged nucleotides induced lacI gene mutations in a dose-dependent manner, whereas unmodified dATP and dGTP did not appear to elicit the mutations. The addition of 50 nmol of 8-OH-dGTP and 2-OH-dATP into an E. coli suspension induced 12- and 9-fold more substitution mutations than the spontaneous event, respectively. The 8-OH-dGTP induced A.T --> C.G transversions, and the 2-OH-dATP elicited G.C --> T.A transversions. These results indicate that the two oxidatively damaged nucleotides are mutagenic in vivo and suggest that 8-OH-dGTP and 2-OH-dATP were incorporated opposite A and G residues, respectively, in the E. coli DNA. This new method enables the evaluation and comparison of the mutagenic potentials of damaged DNA precursors in vivo.
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Affiliation(s)
- M Inoue
- Department of Environmental Oncology, University of Occupational and Environmental Health, 1-1 Iseigaoka, Yahatanishi-ku, Kitakyushu 807-8555, Japan
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37
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Kasai H. Analysis of a form of oxidative DNA damage, 8-hydroxy-2'-deoxyguanosine, as a marker of cellular oxidative stress during carcinogenesis. Mutat Res 1997; 387:147-63. [PMID: 9439711 DOI: 10.1016/s1383-5742(97)00035-5] [Citation(s) in RCA: 812] [Impact Index Per Article: 30.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
8-hydroxy-2'-deoxyguanosine (8-OH-dG) was first reported in 1984 as a major form of oxidative DNA damage product by heated sugar, Fenton-type reagents and X-irradiation in vitro. 8-OH-dG has been detected in cellular DNA using an HPLC-ECD method in many laboratories. Analyses of 8-OH-dG in animal organ DNA after the administration of oxygen radical-forming chemicals will be useful for assessments of their carcinogenic risk. Its analysis in human leucocyte DNA and in urine is a new approach to the assessment of an individual's cancer risk due to oxidative stress. The increase of the 8-OH-dG level in the cellular DNA, detected by HPLC-ECD method, was supported by its immunochemical detection and its enhanced repair activity. The validity of the general use of 8-OH-dG as a marker of cellular oxidative stress is discussed.
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Affiliation(s)
- H Kasai
- Department of Environmental Oncology, Institute of Industrial Ecological Sciences, University of Occupational and Environmental Health, Kitakyushu, Japan.
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Kamiya H, Kasai H. Mutations induced by 2-hydroxyadenine on a shuttle vector during leading and lagging strand syntheses in mammalian cells. Biochemistry 1997; 36:11125-30. [PMID: 9287155 DOI: 10.1021/bi970871u] [Citation(s) in RCA: 50] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
An oxidatively damaged base, 2-hydroxyadenine (2-OH-Ade), was incorporated into a predetermined site of one of the strands {(+)- or (-)-strand} of the double-stranded shuttle vector, pSVK3, and the modified DNAs were transfected into simian COS-7 cells. The nucleotide sequences in which the modified base was incorporated were 5'-GTCGA*C and 5'-CTTA*AG (A* represents 2-OH-Ade). The former is the recognition site for the restriction enzyme SalI, and the latter is that for AflII. The DNAs replicated in the cells were recovered and were transfected again into Escherichia coli. The DNAs recovered from the COS-7 cells transfected with a plasmid containing 2-OH-Ade at either site of the (+)-strand (a template strand for lagging strand synthesis) formed colonies about 50%-70% as frequently as the unmodified DNA. This indicated that the base weakly blocked DNA replication during lagging strand synthesis. On the other hand, the base in the (-)-strand did not appear to affect the efficiency of leading strand synthesis in COS-7 cells. The mutation frequencies of 2-OH-Ade in COS-7 cells were 0.6%-0.1%, depending on the sequence and the strand location. Although the mutation spectra of 2-OH-Ade also differed with sequences and strands, the base elicited substitution and deletion mutations in mammalian cells, as in E. coli. These results indicate that 2-OH-Ade is mutagenic in eukaryotic cells as well as in prokaryotic cells.
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Affiliation(s)
- H Kamiya
- Department of Environmental Oncology, Institute of Industrial Ecological Sciences, University of Occupational and Environmental Health, 1-1 Iseigaoka, Yahatanishi-ku, Kitakyushu 807, Japan
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39
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Murata-Kamiya N, Kamiya H, Kaji H, Kasai H. Mutational specificity of glyoxal, a product of DNA oxidation, in the lacI gene of wild-type Escherichia coli W3110. Mutat Res 1997; 377:255-62. [PMID: 9247622 DOI: 10.1016/s0027-5107(97)00083-3] [Citation(s) in RCA: 42] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
To determine the mutation spectrum of glyoxal, which is produced from DNA by oxygen free-radicals, we analyzed the chromosomal lacI gene of mutants induced by treatment of a wild-type Escherichia coli strain with glyoxal. The cell death and the mutation frequency increased according to the concentration of glyoxal added to the culture medium. The majority of the spontaneous mutations (82%) and that of the glyoxal-induced mutations (50%) were the addition or deletion of a 5'-TGGC-3' sequence at positions 623-634, which was reported to be a mutational hot spot in the lacI gene. In the glyoxal-induced mutants, however, the ratio of base-pair substitutions was increased (35%). Although all types of base-pair substitutions were detected, 78% of the base-pair substitutions occurred at G:C sites. Among them, G:C-->A:T transitions were predominant, followed by G:C-->T:A transversions. These mutations appeared to be distributed randomly within the lacI gene. These results suggest that glyoxal-induced mutations may correlate to mutations induced by oxygen free-radicals.
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Affiliation(s)
- N Murata-Kamiya
- Department of Health Policy and Management, University of Occupational and Environmental Health, Kitakyushu, Japan
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40
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Bouzon M, Marlière P. Human deoxycytidine kinase as a conditional mutator in Escherichia coli. COMPTES RENDUS DE L'ACADEMIE DES SCIENCES. SERIE III, SCIENCES DE LA VIE 1997; 320:427-34. [PMID: 9247021 DOI: 10.1016/s0764-4469(97)81969-5] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
The chemical diversification of DNA precursors was undertaken in Escherichia coil by expressing the human gene for deoxycytidine kinase, and supplying such recombinant strains with nucleoside analogues bearing an altered base or sugar. Arabinocytidine and dideoxycytidine thus became highly toxic to E. coli in the sub-millimolar range. Deoxynucleosides bearing isoadenine (2-aminopurine) and isoguanine (2-hydroxy-6-aminopurine) showed a high mutagenic potency towards the recombinant strains, to an extent comparable to that of the most efficient mutator alleles (dnaQ). These findings open the way to the propagation of chemically remodelled nucleic acids and to the controlled hypermutagenesis of plasmids in vivo.
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Affiliation(s)
- M Bouzon
- Unité de biochimie cellulaire, CNRS Ura 1129, Institut Pasteur, Paris
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41
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Bouzon M, Marlière P. Human deoxycytidine kinase as a conditional mutator in Escherichia coli. COMPTES RENDUS DE L'ACADEMIE DES SCIENCES. SERIE III, SCIENCES DE LA VIE 1997; 320:207-14. [PMID: 9183439 DOI: 10.1016/s0764-4469(97)86928-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
The chemical diversification of DNA precursors was undertaken in Escherichia coli by expressing the human gene for deoxycytidine kinase, and supplying such recombinant strains with nucleoside analogues bearing an altered base or sugar. Arabinocytidine and dideoxycytidine thus became highly toxic to E. coli in the sub-millimolar range. Deoxynucleosides bearing isoadenine (2-aminopurine) and isoguanine (2-hydroxy-6-aminopurine) showed a high mutagenic potency towards the recombinant strains, to an extent comparable to that of the most efficient mutator alleles (dnaQ). These findings open the way to the propagation of chemically remodelled nucleic acids and to the controlled hypermutagenesis of plasmids in vivo.
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Affiliation(s)
- M Bouzon
- Groupe de chimie biologique, unité de biochimie cellulaire, CNRS Ura 1129, Institut Pasteur, Paris
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42
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Kamiya H, Kasai H. Substitution and deletion mutations induced by 2-hydroxyadenine in Escherichia coli: effects of sequence contexts in leading and lagging strands. Nucleic Acids Res 1997; 25:304-11. [PMID: 9016558 PMCID: PMC146441 DOI: 10.1093/nar/25.2.304] [Citation(s) in RCA: 52] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
To evaluate the mutation frequency and the mutation spectrum of 2-hydroxyadenine (2-OH-Ade), an oxidative DNA lesion, the modified base was site-specifically incorporated into a unique restriction enzyme site (SalI, GTCGA*C or AflII, CTTA*AG where A* represents 2-OH-Ade) in single- and double-stranded vectors. The 2-OH-Ade residues were introduced into (+)- and (-)-strands of the double-stranded vectors and into the (+)-strand of single-stranded vectors. When the vectors were transfected intoEscherichia coli, the modified base showed little to no cytotoxicity. The mutation frequencies of 2-OH-Ade in the SalI and AflII sites were approximately 0.8 and 0.07%, respectively, with double-stranded (+)-vectors. An increase in the mutation frequencies was not observed with single-stranded vectors. When incorporated into the (-)-strand, the mutation frequencies of 2-OH-Ade in the SalI and AflII sites were approximately 0.3 and 0.1%, respectively. The mutations observed most frequently were -1 deletions at both positions, in the case of the (+)-strand. On the other hand, we observed that 2-OH-Ade in the (-)-strand induced A-->G and A-->T substitutions. These results indicate that 2-OH-Ade residues in DNA induce substitution and deletion mutations without blocking replication inE.coli.
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Affiliation(s)
- H Kamiya
- Department of Environmental Oncology, Institute of Industrial Ecological Sciences, University of Occupational and Environmental Health, 1-1 Iseigaoka, Yahatanishi-ku, Kitakyushu 807, Japan
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