The Study of the Secondary Structure of a Membrane Protein Bacteriorhodopsin Exposed to Microwaves with a Frequency of 8–18 GHz by Fourier Transform IR Difference Spectroscopy

Fourier transform infrared difference spectroscopy was used to study the effect of millimeter-range electromagnetic radiation on the structure of bacteriorhodopsin under lighting conditions. A detailed analysis of the Fourier IR spectra revealed pronounced structural changes in the region of amide I, amide II and rearrangement of the hydrogen bond network. The well-resolved peaks of the amide bands made it possible to recognize two different components (α-I and α-II) of the α-helical conformation of the opsin. Irreversible conformational changes of bacteriorhodopsin in purple membranes detected by Fourier IR difference spectroscopy suggested that microwaves induced structural rearrangements of proteins unrelated to temperature.