有机磷农药在DNA重组修复试验中的诱变性研究

A STUDY OF MUTAGENICITY OF ORGANOPHOSPHORUS PESTICIDES IN THE DNA REPAIR TEST.

本研究采用枯草杆菌ＤＮＡ重组修复试验，检测了２４种有机磷农药的诱变性，并分析了有机磷的化学结构与诱变性的关系及其可能的诱变机理。结果显示有５种甲基有机磷获阳性结果。构效分析表明，结构类型为（ＲＯ）ａＰＸａ·Ｙａ的有机磷易诱发ＤＮＡ完整性改变，而（ＲＯ）ｂＰＸｃ·Ｙｄ型的有机磷不易诱发ＤＮＡ完整性改变。推测阳性有机磷农药作为烷化剂，主要是使鸟嘌呤的Ｎ－７位甲基化，引起碱基置换；或形成加合物，造成交联，从而引发ＤＮＡ重组修复而致突变。

A total of 24 organophosphorus pesticides (OPPs) were tested for mutagenicity in B. subtilis DNA repair test,and the chemical structure and mutagenicity relationship were analyzed and the mechanism of mutagenicity was discussed.The results showed that five methyl OPPs gave positive values.The structure type of (RO) aPXa.Ya OPP had the tendency of inducing integrity changes of DNA,but the structureal type of (RO)bPXc.Yd OPP did not.The results suggest that positive OPPs may be a kind of alkylating agent,mainly methylated the N-7 position of guanine and induced base pair substitution of formed adduct,and cross linkage to induce DNA recombination and mutation.