亚甲蓝/光化学法对细菌DNA的损伤作用研究

STUDY OF DAMAGING EFFECT OF METHYLENE BLUE/PHOTO CHEMICAL TREATMENT ON BACTERIAL DNA

目的研究亚甲蓝/光化学方法灭活血液中病毒的作用机理。方法用琼脂糖凝胶电泳、质粒转化实验和RAPD扩增技术,对亚甲蓝/光化学处理大肠杆菌质粒DNA的损伤作用进行观察。结果含亚甲蓝浓度为1μmol/L^20μmol/L的质粒DNA,经亚甲蓝/光化学处理后琼脂糖凝胶电泳可观察到质粒DNA的断裂;转化实验结果发现经过化学方法处理的质粒随着处理时间延长和亚甲蓝浓度的提高其转化子总数显著减少;RAPD扩增结果发现随着处理时间的延长RAPD扩增条带逐渐消失。结论亚甲蓝/光化学法可同时在多个位点对DNA有损伤作用。

Objective To study the mechanism of photodynamic inactivation of blood virus by methylene blue （MB）/pho- tochemical treatment. Methods Agarose gel electrophoresis, plasmid transformation experiment and random amplified polymorphic DNA （RAPD） amplification technique were used to observe the damaging effect of MB/photochemical treat- ment on Escherichia coli plasmid DNA. Results After the plasmid DNA containing MB 1 - 20 μmol/L was treated with MB/photochemical method, agarose gel electrophoresis showed that the plasmid was disrupted and appeared as supercoiled form, open circle form and single strand form. Transformation experiment found that the total number of transformants of the plasmids treated with MB/photochemical method significantly decreased with prolonging the treatment time and increasing MB concentration. The results of RAPD amplification found that the RAPD amplified bands gradually disappeared with pro- longing the treatment time. Conclusion MB/photochemical treatment has damaging effect on DNA simultaneously at mul- tinle sites.