title: Copper ions mediate the lethality induced by hydrogen peroxide in low iron conditions in Escherichia coli.
abstract: Iron ions mediate the formation of lethal DNA damage by hydrogen peroxide. However, when cells are depleted of iron ions by the treatment with iron chelators, DNA damage can still be detected. Here we show that the formation of such damage in low iron conditions is due to the participation of copper ions. Copper chelators can inhibit cell inactivation, DNA strand breakage and mutagenesis induced by hydrogen peroxide in cells pre-treated with iron chelators. The Fpg and UvrA proteins play an important role in the repair of DNA lesions formed in these conditions, as suggested by the great sensitivity of the uvrA and fpg mutant strains to the treatment when compared to the wild type strain.
authors.affiliation: Comissão Nacional de Energia Nuclear, Diretoria de Radioproteção e Segurança, Superintendência de Licenciamento e Controle, rua General Severiano, 90, Botafogo, CEP 22294-900, RJ, Rio de Janeiro, Brazil.
authors.forename: C E
authors.initials: CE
authors.lastname: Almeida
authors.forename: R S
authors.initials: RS
authors.lastname: Galhardo
authors.forename: D L
authors.initials: DL
authors.lastname: Felício
authors.forename: J B
authors.initials: JB
authors.lastname: Cabral-Neto
authors.forename: A C
authors.initials: AC
authors.lastname: Leitão
mesh_terms: D015082:2,2'-Dipyridyl / Q000494:pharmacology; D000251:Adenosine Triphosphatases / Q000235:genetics / Q000378:metabolism; D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism; D002455:Cell Division / Q000187:drug effects; D002499:Centrifugation, Density Gradient; D002614:Chelating Agents / Q000494:pharmacology; D003300:Copper / Q000378:metabolism*; D004249:DNA Damage / Q000187:drug effects* / Q000235:genetics; D004260:DNA Repair / Q000235:genetics; D004269:DNA, Bacterial / Q000235:genetics; D004268:DNA-Binding Proteins / Q000235:genetics / Q000378:metabolism; D043382:DNA-Formamidopyrimidine Glycosylase; D004926:Escherichia coli / Q000166:cytology / Q000187:drug effects* / Q000235:genetics / Q000378:metabolism*; D029968:Escherichia coli Proteins; D006861:Hydrogen Peroxide / Q000037:antagonists & inhibitors / Q000494:pharmacology*; D007501:Iron / Q000378:metabolism; D000090463:Iron Deficiencies; D016296:Mutagenesis / Q000187:drug effects / Q000235:genetics; D009153:Mutagens / Q000494:pharmacology; D009699:N-Glycosyl Hydrolases / Q000235:genetics / Q000378:metabolism; D010618:Phenanthrolines / Q000494:pharmacology
chemical_list: D001426:Bacterial Proteins; D002614:Chelating Agents; D004269:DNA, Bacterial; D004268:DNA-Binding Proteins; D029968:Escherichia coli Proteins; D009153:Mutagens; D010618:Phenanthrolines; D015082:2,2'-Dipyridyl; D003300:Copper; C002701:neocuproine; D006861:Hydrogen Peroxide; D007501:Iron; D009699:N-Glycosyl Hydrolases; D043382:DNA-Formamidopyrimidine Glycosylase; C468610:DNA-formamidopyrimidine glycosylase, E coli; C068631:UvrA protein, E coli; D000251:Adenosine Triphosphatases