Heller E P, Rosenkranz E J, McCoy E C, Rosenkranz H S
Mutat Res. 1984 Mar-Apr;131(3-4):89-95. doi: 10.1016/0167-8817(84)90046-4.
The mutagenicity of N-acetoxy-N-2-acetylaminofluorene (N-acetoxy- 2AAF ) for Salmonella typhimuricum TA98 is greatly reduced when compared to that of N-hydroxy-2-aminofluorene. This decrease in mutagenic response is accompanied by the formation of a deoxyguanosine-2-acetylaminofluorene adduct. The deoxyguanosine-2-aminofluorene adduct, characteristic of cells exposed to N - hydroxy-2-aminofluorene, was not detected in N-acetoxy- 2AAF -treated cells. Enzymic deacetylation of N - acetoxy- 2AAF results in restoration of potent mutagenicity. N-Acetoxy-2-acetylamino-7- iodofluorene is also more mutagenic than N-acetoxy- 2AAF . Because the acetylated and unacetylated guanine adducts induce greatly different configurational changes, the results may be indicative that the introduction of the syn configuration and a possible shift to the Z-conformation at the mutational hot spot of Salmonella typhimurium TA98 [(dG-dC)8] results in reduced mutagenic potency.
与N-羟基-2-氨基芴相比，N-乙酰氧基-N-2-乙酰氨基芴（N-乙酰氧基-2-AAF）对鼠伤寒沙门氏菌TA98的致突变性大大降低。致突变反应的这种降低伴随着脱氧鸟苷-2-乙酰氨基芴加合物的形成。在经N-乙酰氧基-2-AAF处理的细胞中未检测到暴露于N-羟基-2-氨基芴的细胞所特有的脱氧鸟苷-2-氨基芴加合物。N-乙酰氧基-2-AAF的酶促脱乙酰化导致强效致突变性的恢复。N-乙酰氧基-2-乙酰氨基-7-碘芴的致突变性也比N-乙酰氧基-2-AAF更强。由于乙酰化和未乙酰化的鸟嘌呤加合物诱导的构象变化差异很大，结果可能表明在鼠伤寒沙门氏菌TA98的突变热点[(dG-dC)8]处引入顺式构型并可能转变为Z构象会导致致突变效力降低。
