Non-thermal protein structural change by THz pulsed light irradiation

Terahertz (THz) light that resonates with the vibrational frequency of hydrated water molecules, can alter functional expression of proteins. Previous studies have shown that high-intensity THz light promotes actin fiber formation, but such mechanism is not comprehensively investigated. Here, we aim to clarify this mechanism by irradiating actin solution with THz pulsed light of lower average power and higher electric field intensity to suppress thermal effects. We compare the degree of fiber formation with and without irradiation. The result shows the contribution of electric field intensity in the accelerated actin fiber formation and clarifies the existence of non-thermal effects.