稀土镧离子对大肠杆菌基因组DNA的影响

背景与目的: 通过研究硝酸镧溶液对大肠杆菌基因组DNA的作用，探讨稀土镧离子对原核生物的遗传毒性效应。 材料与方法: 用含硝酸镧分别为10、40、80、160、320 mg/L的LB培养基培养大肠杆菌,以不添加硝酸镧组作为对照,于培养10 h,15 h和20 h后分别采样提取总DNA,琼脂糖凝胶电泳; 并用含硝酸镧分别为50、200、400、800、1 600 mg/L的LB培养基培养大肠杆菌, 未添加硝酸镧组作为对照, 于培养30 h后分别采样提取总DNA,琼脂糖凝胶电泳。 结果: 高剂量镧离子组大肠杆菌基因组DNA出现降解或交联现象，电泳带型荧光减弱，不清晰或滞留于点样孔不能泳出。 结论: 镧离子对大肠杆菌基因组DNA可能具有降解或交联作用。

Effects of Lanthanide Ions in Rare Earths on Genomic DNA of E. coli

BACKGROUND ＆ AIM: To investigate genotoxic effect of lanthanide ions on prokaryote by observing the effects of lanthanide nitrate on genomic DNA of E.coli. MATERIALS AND METHODS: TreatmentⅠ: E.coli was cultured in LB medium with different concentrations of lanthanide nitrate (10,40,80,160,320 mg/L), LB medium without lanthanide nitrate was the control. Genomic DNA was extracted at 10, 15, and 20 h. Then Agarose gel electrophoresis was performed Treat mentⅡ: E.coli was cultwred in LB medium with different concentrations of lanthanide nitrate (50,200,400,800,1 600 mg/L) LB medium without lanthanide nitrate was the control. Genomic DNA was extracted at 30 h. Then Agarose gel electrophoresis was performed RESULTS: DNA degradation or cross-linkage was produced by high concentrations of lanthanide ions. CONCLUSION: Lanthanide ions affected degradation and crosslinking on genomic DNA of E.coli.