Details

Autor(en) / Beteiligte

• DAUBERSIES, P
• GALIEGUE-ZOUITINA, S
• KOFFEL-SCHWARTZ, N
• FUCHS, R. P. P
• LOUCHEUX-LEFEBVRE, M.-H
• BAILLEUL, B

Titel

Mutation spectra of the two guanine adducts of the carcinogen 4-nitroquinoline 1-oxide in Escherichia coli. Influence of neighbouring base sequence on mutagenesis

Ist Teil von

• Carcinogenesis (New York), 1992-03, Vol.13 (3), p.349-354

Ort / Verlag

Oxford: Oxford University Press

Erscheinungsjahr

1992

Quelle

MEDLINE

Beschreibungen/Notizen

• When the chemical carcinogen 4-nitroquinoline 1-oxide binds to DNA in vitro, two major adducts are formed, both at guanine residues, but at different positions, i.e. the C8 or the N2 position. Well-defined adducts (either C8 or N2 guanine adducts) can be formed in vitro by reacting DNA with 4-actoxyaminoquinoline 1-oxide (Ac-4HAQO) under different reaction conditions. Forward mutations induced by each of both main 4NQO adducts in the tetracycline resistance gene of pBR322 were determined. In total, 30 independent 4NQO-induced mutations were characterized, showing mainly base-pair substitution mutations and some frameshift mutations. We have observed that the 5' neighbouring base influences the specificity of dGuo-N2-AQO induced base-pair substitutions mutagenesis; a similar effect does not occur with dGuo-C8-AQO. This study reveals the importance of the N2 guanine adduct in the mutagenesis induced by 4NQO in vivo.