title: Leading versus lagging strand mutagenesis induced by 7,8-dihydro-8-oxo-2'-deoxyguanosine in Escherichia coli.
abstract: We have previously shown that a single N-2-acetylaminofluorene (AAF) adduct bound to the C-8 position of a guanine residue located within plasmids containing the unidirectional ColE1 origin of replication induces a 20-fold higher mutation frequency when the adduct is located in the lagging strand as compared to the leading strand. In this study, single 7,8-dihydro-8-oxo-2'-deoxyguanosine (8-oxodG) lesions have been introduced in the leading and lagging strand orientation within the same sequence context as for the AAF adducts. The induced frequency of guanine to thymine transversions has been measured, using a specific PCR-based quantitative assay, in strains deficient in the repair of the oxidative lesion. The potential involvement of the UvrABC excision repair system in the removal of 8-oxodG has also been investigated and ruled out. Concerning the mutation frequency asymmetry, in contrast to AAF adducts, 8-oxodG adducts induce the same mutation frequency, irrespective of their location in the leading or lagging strands. This striking difference between 8-oxodG and dGuo-C8-AAF adducts is discussed in terms of their differential capacity to block DNA replication.
authors.affiliation: Cancérogenèse et Mutagenèse Moleculaire et Structurale, Unité Propre de Recherche (#9003) du Centre National de la Recherche Scientifique IRCAD, Hopitaux Universitaires, Strasbourg, France.
authors.forename: J
authors.initials: J
authors.lastname: Wagner
authors.forename: H
authors.initials: H
authors.lastname: Kamiya
authors.forename: R P
authors.initials: RP
authors.lastname: Fuchs
mesh_terms: D015073:2-Acetylaminofluorene / Q000633:toxicity; D000080242:8-Hydroxy-2'-Deoxyguanosine; D000241:Adenosine / Q000235:genetics; D000251:Adenosine Triphosphatases / Q000187:drug effects / Q000235:genetics; D001426:Bacterial Proteins / Q000187:drug effects / Q000235:genetics; D001482:Base Composition; D018736:DNA Adducts / Q000235:genetics* / Q000494:pharmacology; D045647:DNA Glycosylases; D004265:DNA Helicases; D004260:DNA Repair; D004251:DNA Transposable Elements; D004268:DNA-Binding Proteins / Q000187:drug effects / Q000235:genetics; D043382:DNA-Formamidopyrimidine Glycosylase; D003849:Deoxyguanosine / Q000031:analogs & derivatives* / Q000235:genetics / Q000633:toxicity; D004706:Endodeoxyribonucleases; D004926:Escherichia coli / Q000187:drug effects / Q000235:genetics*; D029968:Escherichia coli Proteins; D016368:Frameshift Mutation; D006147:Guanine; D016296:Mutagenesis; D009152:Mutagenicity Tests; D009699:N-Glycosyl Hydrolases / Q000187:drug effects / Q000235:genetics; D010744:Phosphoric Monoester Hydrolases / Q000187:drug effects / Q000235:genetics; D010957:Plasmids / Q000235:genetics; D016133:Polymerase Chain Reaction / Q000379:methods; D011755:Pyrophosphatases; D018741:Replication Origin; D013941:Thymine
chemical_list: D001426:Bacterial Proteins; D018736:DNA Adducts; D004251:DNA Transposable Elements; D004268:DNA-Binding Proteins; D029968:Escherichia coli Proteins; C058093:UvrB protein, E coli; D006147:Guanine; D000080242:8-Hydroxy-2'-Deoxyguanosine; D015073:2-Acetylaminofluorene; D004706:Endodeoxyribonucleases; C066567:UvrC protein, E coli; D010744:Phosphoric Monoester Hydrolases; D045647:DNA Glycosylases; D009699:N-Glycosyl Hydrolases; C061738:mutY adenine glycosylase; D043382:DNA-Formamidopyrimidine Glycosylase; C468610:DNA-formamidopyrimidine glycosylase, E coli; C068631:UvrA protein, E coli; D000251:Adenosine Triphosphatases; D011755:Pyrophosphatases; C052211:mutT protein, E coli; D004265:DNA Helicases; D003849:Deoxyguanosine; D000241:Adenosine; D013941:Thymine