典型醛类污染物与细胞DNA分子的结合作用

为了研究甲醛、乙醛和丙烯醛等 3种典型醛类污染物与细胞DNA的结合作用 ,探讨其遗传毒性效应和机制 ,采用体外测试系统 ,应用紫外光谱移动法和高效液相色谱法研究结合位点 .结果表明 ,醛类污染物染毒细菌DNA紫外吸收峰位移不显著 ;但提取的细菌DNA与甲醛进行试管反应体系紫外位移显著 ;醛类污染物染毒真核细胞致DNA分子紫外吸收峰位移显著 ;乙醛与脱氧鸟苷酸的试管反应经NaBH₄ 还原后经HPLC分离检测 ,产物初步定性为N2-乙基鸟苷加合物 .说明 3种醛类污染物能够与细胞DNA结合而体现遗传毒性 ,鸟苷的N2位可能是共价加合的位点 .

The Bindings of Typical Aldehydes Pollutants with Cell DNA

The bindings of 3 kinds of aidehyde pollutants,formaldehyde,acetaldehyde,acrolein,with both prokaryotic and eukaryotic DNA,and their genotoxic effect and mechanism were conducted by the shifts of maximum UV absorption peak to determine binding effects and by HPLC to determine binding sites in vitro model system.The shifts of maximum UV absorption peak of prokaryotic DNA contaminated by 3 kinds of aldehyde pollutants are not significant;but after the DNA extracted from prokaryotic bacteria reacting with formaldehyde in tube,the shifts of maximum UV absorption peak of DNA are significant;the shifts of maximum UV absorption peak of eukaryotic DNA contaminated by 3 kinds of aldehyde pollutants are significant also.The reacition of acetaldehyde with dG reduced by NaBH 4 was separated and detected by HPLC,the product was determined qualitatively as N2-ethaldeoxyguanosine adduct.The 3 kinds of aldehyde pollutants could bind with cellular DNA to express genotoxic effects;and the N2 site of deoxyguanosine is the possible covalent binding site.