Study of the effects of 3.1 THz radiation on the expression of recombinant red fluorescent protein (RFP) in E. coli

In recent years, many studies have been conducted to investigate the non-thermal effects of THz radiation on different organisms, but further studies are needed to fully elucidate the effects, especially on the molecular level. In this study, we explored the effects of at 3.1 THz radiation on protein expression in Escherichia coli (E. coli) using red fluorescent protein as a reporter molecule. After 8 hours of continuous THz irradiation of bacteria on LB (Luria-Bertani) solid plates at an average power of 33 mW/cm2 and 10 Hz pulse repetition frequency, we found that the plasmid copy number, protein expression and fluorescence intensity of bacteria from the irradiated area were 3.8-, 2.7-, and 3.3 times higher than in bacteria from the un-irradiated area, respectively. These findings suggest that plasmid replication changed significantly in bacteria exposed to 3.1 THz radiation, resulting in increased protein expression as evidenced by increased fluorescence intensity of the RFP reporter.