二氯乙腈对大肠杆菌基因表达的影响

为探究二氯乙腈（DCAN）对大肠杆菌（E.coli）基因表达的影响及相应的毒性作用，采用自组织映射（SOM）聚类及剂量效应关系分析方法考察了E.coli在不同剂量DCAN暴露120min过程中其基因表达状况.结果表明：随时间及浓度改变E.coli基因表达具有动态性；在DCAN浓度为1.429×10^-3mg/L时，多个参与应急反应（SOS response）调节、氧化还原应激及普通应激的基因启动子活性发生改变，导致DNA损伤、氧化应激加剧，细胞生物化学和物理稳态可能受到干扰；此外，毒性终点结果表明DNA损伤是DCAN主要的毒性作用模式.

Effects of dichloroacetonitrile on gene expression of Escherichia coli

To explore the effects of dichloroacetonitrile (DCAN) on gene expression of E.coli and corresponding toxic effect, the gene expression of E.coli under different dosages of DCAN for 120min was identified by self-organizing map (SOM) clustering and dose-response relationship. The results showed that the genes expression was dynamically affected under varied exposure time and concentration of DCAN. When the concentration of DCAN was 1.429×10^-3mg/L, the activity of multiple gene promoter included in SOS response regulation, oxidative and general stress had been changed. These consequences further resulted in DNA damage and more severe oxidative stress on the cells, made them bio-chemically and physically unstable. The results also clarified that DNA damage is the main toxic mode of DCAN through different pathways.