Thomas H F, Hartman P E, Mudryj M, Brown D L
Mutat Res. 1979 Jul;61(2):129-51. doi: 10.1016/0027-5107(79)90121-0.
Purified native Hemophilus influenzae DNA is relatively insusceptible to nitrous acid (NA) mutagenesis in vitro, but is readily mutated following denaturation. NA mutagenicity for duplex DNA is significantly increased in the presence of various alcohols, glycols, phenols or primary amines. Phenol-extracted DNA contains dissociable contaminants of low molecular weight that enhance NA mutagenesis. Enhancement of NA mutagenesis by phenol and by spermine is due to the formation of unstable molecular species. We propose that reactive organic nitroso compounds are formed which then serve as delivery vehicles to promote mutagenicity of native DNA, perhaps via transnitrosation reactions. Similar reactions probably occur in vivo to promote NA-induced base substitution (but not frameshift) mutations in Salmonella typhimurium and in Escherichia coli. The possible significance of these observations to carcinogenesis is discussed.
纯化的天然流感嗜血杆菌DNA在体外相对不易受到亚硝酸（NA）诱变，但变性后很容易发生突变。在各种醇、二醇、酚或伯胺存在的情况下，NA对双链DNA的诱变性显著增加。苯酚提取的DNA含有可解离的低分子量污染物，可增强NA诱变作用。苯酚和精胺对NA诱变的增强作用是由于形成了不稳定的分子物种。我们提出，形成了反应性有机亚硝基化合物，然后它们作为传递载体，可能通过转亚硝化反应促进天然DNA的诱变性。类似的反应可能在体内发生，以促进NA诱导的鼠伤寒沙门氏菌和大肠杆菌中的碱基取代（但不是移码）突变。讨论了这些观察结果对致癌作用可能具有的意义。
