Yamasaki H, Pulkrabek P, Grunberger D, Weinstein I B
Cancer Res. 1977 Oct;37(10):3756-60.
Purified duck reticulocyte DNA was reacted in vitro with [9-14C]-N-acetoxy-N-acetyl-2-aminofluorene. Hydrolysis of the [14C]-N-acetyl-2-aminofluorene-modified DNA followed by Sephadex LH-20 column chromatography showed that 85% of the DNA-bound [14C]-N-acetyl-2-aminofluorene was N-(deoxyguanosin-8-yl)-N-acetyl-2-aminofluorene and 15% was 3-(deoxyguanosin-N2-yl)-N-acetyl-2-aminofluorene. When this modified DNA was incubated with the single strand-specific nuclease, S1, and the undigested fraction of the DNA was analyzed, there was preferential loss of the quanosine C-8 adduct from the DNA. Moreover, analysis of the nucleosides released by exposure of N-acetyl-2-aminofluorene-modified DNA to a single strand-specific nuclease from Neurospora crassa showed only the guanosine C-8 adduct in the supernatant fraction. These results suggest that, whereas the N-(deoxyguanosin-8-yl)-N-acetyl-2-aminofluorene adduct in DNA causes major conformational changes in the double-stranded helix and localized regions of denaturation, the 3-(deoxyguanosin-N2-yl)-N-acetyl-2-aminofluorene adduct does not cause major distortions of the native DNA structure.
将纯化的鸭网织红细胞DNA与[9-¹⁴C]-N-乙酰氧基-N-乙酰基-2-氨基芴在体外进行反应。对[¹⁴C]-N-乙酰基-2-氨基芴修饰的DNA进行水解，然后通过葡聚糖凝胶LH-20柱色谱分析表明，与DNA结合的[¹⁴C]-N-乙酰基-2-氨基芴中85%是N-(脱氧鸟苷-8-基)-N-乙酰基-2-氨基芴，15%是3-(脱氧鸟苷-N²-基)-N-乙酰基-2-氨基芴。当将这种修饰的DNA与单链特异性核酸酶S1一起温育，并对DNA的未消化部分进行分析时，发现DNA中的鸟苷C-8加合物优先丢失。此外，对N-乙酰基-²-氨基芴修饰的DNA暴露于粗糙脉孢菌的单链特异性核酸酶后释放的核苷进行分析，结果表明在上清液部分仅存在鸟苷C-8加合物。这些结果表明，虽然DNA中的N-(脱氧鸟苷-8-基)-N-乙酰基-2-氨基芴加合物会导致双链螺旋发生主要构象变化和局部变性区域，但3-(脱氧鸟苷-N²-基)-N-乙酰基-2-氨基芴加合物不会引起天然DNA结构的主要扭曲。
