Mutation and DNA modification in Salmonella exposed to N-nitrosodimethylamine under UVA- and sunlight-irradiation

Sakae Arimoto-Kobayashi, Beryl M. Tracey, Mieko Asao, Hikoya Hayatsu, Peter B. Farmer

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8 Citations (Scopus)


Previously, we reported that when Salmonella typhimurium and Escherichia coli were treated with N-nitrosodimethylamine (NDMA) under irradiation with ultraviolet-A (UVA), mutagenesis of the bacteria took place without externally added activation enzymes. We also observed the formation of O6-methylguanine (O6-meG), N7-methylguanine (N7-meG) and 7,8-dihydro-8-oxodeoxyguanosine (8-oxodG) in calf thymus DNA treated with NDMA plus UVA. In this study, we observed the mutagenicity of NDMA under irradiation of natural sunlight in S. typhimurium. Furthermore, we detected the formation of O6-meG, N7-meG and 8-oxodG in calf thymus DNA treated with NDMA plus simulated sunlight. Regarding the mutagenesis of S. typhimurium by NDMA plus UVA, we have now identified and quantified O6-meG formed in the genomic DNA of the bacteria under conditions of the mutagenesis. Copyright (C) 1999 Elsevier Science B.V.

Original languageEnglish
Pages (from-to)413-419
Number of pages7
JournalMutation Research - Genetic Toxicology and Environmental Mutagenesis
Issue number2
Publication statusPublished - Aug 18 1999



  • 7,8-Dihydro-8-oxo-deoxyguanosine
  • Mutation
  • N-Nitrosodimethylamine
  • O-Methylguanine
  • Sunlight
  • UVA

ASJC Scopus subject areas

  • Genetics
  • Health, Toxicology and Mutagenesis

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