Reverse chemical mutagenesis: Identification of the mutagenic lesions resulting from reactive oxygen species-mediated damage to DNA

Daniel I. Feig, Lawrence C. Sowers, Lawrence A. Loeb

Research output: Contribution to journalArticle

188 Scopus citations


An understanding of the contribution of reactive oxygen species to mutagenesis has been hampered by the vast number of different chemical modifications they cause in DNA. Even though many of these DNA alterations have been catalogued, the identification of specific lesions that cause mutations has depended on testing one modification at a time. In this study we present another approach to identify key mutagenic lesions from a pool of oxidatively modified nucleotides. dCTP was treated with an oxygen radical- generating system containing FeSO4, H2O2, and ascorbic acid. The modification products were separated by reverse-phase and anion-exchange HPLC and then incorporated by human immunodeficiency virus reverse transcriptase into a DNA that contains a target gene for scoring for mutations. One of the mutagenic species isolated was identified as 5-hydroxy-2'-deoxycytidine. It is incorporated efficiently into DNA and causes C → T transitions in Escherichia coli at a frequency of 2.5%, which is more mutagenic than any previously identified oxidative DNA lesion.

Original languageEnglish (US)
Pages (from-to)6609-6613
Number of pages5
JournalProceedings of the National Academy of Sciences of the United States of America
Issue number14
StatePublished - Jul 5 1994
Externally publishedYes



  • DNA damage
  • carcinogens
  • human immunodeficiency virus reverse transcriptase
  • mutagens
  • oxygen free radicals

ASJC Scopus subject areas

  • General

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