DNA damage by a single intense shot of soft X-rays emitted by a laser-produced plasma

A suitable plane transmission line was developed and its behaviour analysed at 900 MHz radiofrequency fields to study the DNA mutability and repair of microorganisms. In this work, utilizing such a device, we investigated the behaviour of the DNA mutability and repair of Escherichia coli strains. The transmission line was very simple and versatile in changing its characteristic resistance and field intensity by varying its sizes. In absence of cell samples inside the transmission line, the relative modulation of the electric and/or magnetic field was ±31% with respect to the mean values, allowing the processing of more samples at different exposure fields in a single run. Slight decrease in spontaneous mutability to rifampicin-resistance of the E. Coli JC411 strain, was demonstrated in mismatch-repair proficient samples exposed to the radio-frequency fields during their growth on solid medium.

本研究开发了一款适配的平面传输线，并在900 MHz射频场中对其性能进行了分析，以开展微生物DNA突变性与修复机制的相关研究。本研究利用该装置，针对大肠杆菌（Escherichia coli）菌株的DNA突变性与修复特性展开了探究。该传输线结构简洁，可通过调整自身尺寸灵活调节其特性阻抗与场强。当传输线内未放置细胞样本时，电场及/或磁场的相对调制幅度相对于平均值可达±31%，这使得单次实验即可处理多组处于不同辐照场强下的样本。实验证实，在固体培养基上生长且暴露于射频场的错配修复功能完整的大肠杆菌JC411菌株，其对利福平抗性的自发突变率出现了小幅下降。