UV照射大肠杆菌对其吸收光谱的影响

Effect of UV on the Absorption Spectra of E.coli Cells

探讨了样品池溶液及分光光度计内置紫外光对大肠杆菌吸收光谱测定的影响。发现样品池溶液(2.8 mL双蒸水+0.1 mL生理盐水+0.1 mL LB培养基)较为合理,既给细菌提供了有利的生存环境,又对细胞的紫外吸收影响较小;研究同时发现在257 nm波段150 s内细胞吸收强度基本没有变化,说明内置的紫外光不会影响试验测定结果。在此基础上,研究了UV照射0,20,40,60,80,120 s大肠杆菌吸收光谱的变化情况。结果显示随着UV照射剂量的增加,大肠杆菌吸收光谱存在一个先降后升再降的现象。该现象反映了辐射中细胞损伤死亡和修复存活的生物学效应。该研究从光谱学角度探讨了UV对大肠杆菌细胞的损伤作用,对利用光谱技术研究细胞的辐射损伤、死亡和修复具有一定参考意义。

The present article studied the effects of different solutions in sample cavity on the spectra of E. coli. It is shown that the solutions of 2.8 mL distilled water and 0.1 mL LB and 0.1 mL PBS is the best, because it not only supplies good living condition but also has less effect on the spectra of E. coli. And it was found that UV in spectrophotometer has no effect on the mensuration result. On the basis of these studies the absorption spectra of E. coli irradiated by different doses UV were investigated. It is shown that there is a declining-rising-declining phenomenon in the spectra of E. coli with the dose increasing. This reflects the wound healing process of E. coli. Spectroscopic technique is helpful for the study of cell＇s wound healing.