Evidence for a major premutagenic ethyldeoxythymidine-DNA adduct in an in vivo system: N-nitroso-N-ethylurea-treated Salmonella typhimurium.
Evidence for a major premutagenic ethyldeoxythymidine-DNA adduct in an in vivo system: N-nitroso-N-ethylurea-treated Salmonella typhimurium.
复制标题
体内系统中存在主要诱变前乙基脱氧胸苷-DNA 加合物的证据：N-亚硝基-N-乙基脲处理的鼠伤寒沙门氏菌。
DOI：
10.1093/carcin/6.10.1513
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发表时间：
1985
期刊：
影响因子：
4.7
通讯作者：
Guttenplan,JB
中科院分区：
文献类型：
--
作者：
Hu,YC;Guttenplan,JB
Mutagenesis induced by N-nitroso-N-ethylurea (NEU) was assayed in four strains ofSalmonella typhimuriumwhich are known to be reverted to histidine prototrophy by mutations at A-T base pairs and by extragenic suppression. NEU-induced revertants were characterized for the presence of extragenic suppressors by their sensitivities to the histidine analogue, thiazolealanine. In strains carrying the plasmid, pKM101, only a small percentage of the revertants was due to suppressors, indicating that NEU gives rise to a major pre-mutagenic adenine or thymidine-DNA adduct. In strains without plasmid, mutagenesis was much less efficient and resulted mainly from suppressors. Apparently error-prone DNA-repair plays an important role in mutagenesis via the A or T-DNA adduct in the plasmid-containing strains. Ethylmethanesulfonate (EMS), a mutagen known to form ethyladenines but not ethylthymidines, induced mutagenesis that resulted mainly from suppressors in all strains, and there was little inter-strain difference in the sensitivity to EMS. Since NEU, but not EMS, forms ethylthymidines in appreciable yield, and only NEU induced high percentages of revertants with mutations at A-T base pairs, it appears that at least one ethylthymidine is a major premutagenic adduct in NEU-induced mutagenesis.
