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Title: Formation of 8-hydroxy(deoxy)guanosine and generation of strand breaks at guanine residues in DNA by singlet oxygen

Abstract

Singlet molecular oxygen ({sup 1}O{sub 2}) was generated in aqueous solution (H{sub 2}O or D{sub 2}O) at 37 C by the thermal dissociation of the endoperoxide of 3,3'-(1,4-naphthylidene) dipropionate (NDPO{sub 2}). Guanosine and deoxyguanosine quench {sup 1}O{sub 2} with overall quenching rate constants of 6.2 {times} 10{sup 6} M{sup {minus}1} s{sup {minus}1} and 5.2 {times} 10{sup 6} M{sup {minus}1} s{sup {minus}1}, respectively. Reaction with {sup 1}O{sub 2} results in the formation of 8-hydroxyguanosine (8-OH-Guo) and 8-hydroxydeoxyguanosine (8-OH-dGuo), respectively, with a yield of 1.5% at 1 mM substrate with an NDPO{sub 2} concentration of 40 mM; a corresponding 8-hydroxy derivative is not formed from deoxyadenosine. in D{sub 2}O the yield of 8-OH-Guo is 1.5-fold that in H{sub 2}O. Sodium azide suppresses 8-OH-Guo and 8-OH-dGuo production. in contrast, the hydroxyl radical scavengers, tert-butanol, 2-propanol, or sodium formate, do not decrease the production of the 8-OH derivatives. The formation of 8-OH derivatives is significantly increased (2-5-fold) by thiols such as dithiothreitol, glutathione, cysteine, and cysteamine. With use of a plasmid containing a fragment of the mouse metallothionein 1 promoter (pMTP3') and a novel end-labeling technique, the position of {sup 1}O{sub 2}-induced single-strand breaks in DNA was examined. Strand breaks occur selectively at dGuo;more » no major differences (hot spots) were observed between individual guanines.« less

Authors:
; ; ;  [1];  [2]
  1. (Univ. Duesseldorf (West Germany))
  2. (Max-Planck-Inst. fuer Strahlenchemi, Muelheim (West Germany))
Publication Date:
OSTI Identifier:
5029122
Resource Type:
Journal Article
Resource Relation:
Journal Name: Biochemistry; (United States); Journal Volume: 30:25
Country of Publication:
United States
Language:
English
Subject:
62 RADIOLOGY AND NUCLEAR MEDICINE; DNA; AUTORADIOGRAPHY; GUANINE; STRAND BREAKS; OXYGEN; BIOLOGICAL EFFECTS; AQUEOUS SOLUTIONS; HEAVY WATER; METALLOTHIONEIN; PEROXIDES; PLASMIDS; THIOLS; AMINES; AROMATICS; AZAARENES; CELL CONSTITUENTS; DISPERSIONS; ELEMENTS; HETEROCYCLIC COMPOUNDS; HYDROGEN COMPOUNDS; HYDROXY COMPOUNDS; METALLOPROTEINS; MIXTURES; NONMETALS; NUCLEIC ACIDS; ORGANIC COMPOUNDS; ORGANIC NITROGEN COMPOUNDS; ORGANIC SULFUR COMPOUNDS; OXYGEN COMPOUNDS; PROTEINS; PURINES; SOLUTIONS; WATER; 550601* - Medicine- Unsealed Radionuclides in Diagnostics

Citation Formats

Devasagayam, T.P.A., Obendorf, M.S.W., Schulz, W.A., Sies, H., and Steenken, S. Formation of 8-hydroxy(deoxy)guanosine and generation of strand breaks at guanine residues in DNA by singlet oxygen. United States: N. p., 1991. Web. doi:10.1021/bi00239a029.
Devasagayam, T.P.A., Obendorf, M.S.W., Schulz, W.A., Sies, H., & Steenken, S. Formation of 8-hydroxy(deoxy)guanosine and generation of strand breaks at guanine residues in DNA by singlet oxygen. United States. doi:10.1021/bi00239a029.
Devasagayam, T.P.A., Obendorf, M.S.W., Schulz, W.A., Sies, H., and Steenken, S. 1991. "Formation of 8-hydroxy(deoxy)guanosine and generation of strand breaks at guanine residues in DNA by singlet oxygen". United States. doi:10.1021/bi00239a029.
@article{osti_5029122,
title = {Formation of 8-hydroxy(deoxy)guanosine and generation of strand breaks at guanine residues in DNA by singlet oxygen},
author = {Devasagayam, T.P.A. and Obendorf, M.S.W. and Schulz, W.A. and Sies, H. and Steenken, S.},
abstractNote = {Singlet molecular oxygen ({sup 1}O{sub 2}) was generated in aqueous solution (H{sub 2}O or D{sub 2}O) at 37 C by the thermal dissociation of the endoperoxide of 3,3'-(1,4-naphthylidene) dipropionate (NDPO{sub 2}). Guanosine and deoxyguanosine quench {sup 1}O{sub 2} with overall quenching rate constants of 6.2 {times} 10{sup 6} M{sup {minus}1} s{sup {minus}1} and 5.2 {times} 10{sup 6} M{sup {minus}1} s{sup {minus}1}, respectively. Reaction with {sup 1}O{sub 2} results in the formation of 8-hydroxyguanosine (8-OH-Guo) and 8-hydroxydeoxyguanosine (8-OH-dGuo), respectively, with a yield of 1.5% at 1 mM substrate with an NDPO{sub 2} concentration of 40 mM; a corresponding 8-hydroxy derivative is not formed from deoxyadenosine. in D{sub 2}O the yield of 8-OH-Guo is 1.5-fold that in H{sub 2}O. Sodium azide suppresses 8-OH-Guo and 8-OH-dGuo production. in contrast, the hydroxyl radical scavengers, tert-butanol, 2-propanol, or sodium formate, do not decrease the production of the 8-OH derivatives. The formation of 8-OH derivatives is significantly increased (2-5-fold) by thiols such as dithiothreitol, glutathione, cysteine, and cysteamine. With use of a plasmid containing a fragment of the mouse metallothionein 1 promoter (pMTP3') and a novel end-labeling technique, the position of {sup 1}O{sub 2}-induced single-strand breaks in DNA was examined. Strand breaks occur selectively at dGuo; no major differences (hot spots) were observed between individual guanines.},
doi = {10.1021/bi00239a029},
journal = {Biochemistry; (United States)},
number = ,
volume = 30:25,
place = {United States},
year = 1991,
month = 6
}
  • Ionizing radiation causes the formation of strand breaks in cellular DNA, as well as other types of lesions in the chromatin of cells. Some of the earliest investigations of the molecular basis of radiation-induced damage and the implications of enzymatic repair were done by Dr. H. S. Kaplan. Because it is difficult to assay for DNA lesions in the large mammalian genome, the authors have developed a method of assaying for DNA double-strand breaks in the supercoiled nucleosome-complexed Simian virus 40 (SV40) genome, irradiated intracellularly. In this communication they present their measurements of the DNA double-strand breaks (DSBs) to single-strandmore » breaks (SSBs) ratio obtained from the intracellularly irradiated SV40 genome. After cobalt gamma ray and X ray irradiations, this ratio is about 1/10. Their methods and results are compared with pertinent data in the literature. If the DSBs/SSBs ratio of 1/10 for cellular chromatin is correct, a substantial number of DNA double-strand breaks are formed in a mammalian cell after moderate doses (1 Gy) of radiation. The implications of different types of DNA double-strand breaks are discussed.« less
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  • This work describes a neutral and alkaline elution method for measuring DNA single-strand breaks (SSBs), DNA double-strand breaks (DSBs), and DNA-DNA crosslinks in rat testicular germ cells after treatments in vivo or in vitro with both chemical mutagens and gamma-irradiation. The methods depend upon the isolation of testicular germ cells by collagenase and trypsin digestion, followed by filtration and centrifugation. {sup 137}Cs irradiation induced both DNA SSBs and DSBs in germ cells held on ice in vitro. Irradiation of the whole animal indicated that both types of DNA breaks are induced in vivo and can be repaired. A number ofmore » germ cell mutagens induced either DNA SSBs, DSBs, or cross-links after in vivo and in vitro dosing. These chemicals included methyl methanesulfonate, ethyl methanesulfonate, ethyl nitrosourea, dibromochlorpropane, ethylene dibromide, triethylene melamine, and mitomycin C. These results suggest that the blood-testes barrier is relatively ineffective for these mutagens, which may explain in part their in vivo mutagenic potency. This assay should be a useful screen for detecting chemical attack upon male germ-cell DNA and thus, it should help in the assessment of the mutagenic risk of chemicals. In addition, this approach can be used to study the processes of SSB, DSB, and crosslink repair in DNA of male germ cells, either from all stages or specific stages of development.« less
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