King's College London

Research portal

Evidence of involvement of multiple sites of metabolism in the in vivo covalent binding of dibenzo[a,h]pyrene to DNA

Research output: Contribution to journalArticle

G A Marsch, R Jankowiak, G J Small, N C Hughes, D H Phillips

Original languageEnglish
Pages (from-to)765-72
Number of pages8
JournalChemical Research in Toxicology
Volume5
Issue number6
Publication statusPublished - 1992

King's Authors

Abstract

The in vivo formation of dibenzo[a,h]pyrene-DNA adducts in mouse skin was assessed by laser-excited fluorescence spectroscopy at 77 and 4.2 K. Two adducts were identified with fluorescence origin bands at approximately 383.5 and 407.2 nm, and these were shown to possess pyrene and benzo[a]pyrene (B[a]P) chromophores, respectively. Both DNA-bound chromophores displayed considerable electron-phonon coupling and likely assume a highly base-stacked or quasi-intercalated configuration within DNA duplexes. The presence of B[a]P and pyrene aromatic systems indicates that two-electron or monooxygenation metabolism occurred on either the a or h benzo moieties (which are equivalent) in the former case, and on both these rings in the latter case. The presence of two adduct species agrees with 32P-postlabeling analysis of the DNA, which showed the presence of two major adducts in both thin-layer and high-performance liquid chromatographic separations.

View graph of relations

© 2018 King's College London | Strand | London WC2R 2LS | England | United Kingdom | Tel +44 (0)20 7836 5454