Investigation of the mechanism underlying the effects of electric fields on insect acetylcholinesterase activity

Electro pest control technology has garnered significant attention as an emerging green insecticidal approach due to its high efficiency and environmental friendliness. However, its underlying mechanisms, particularly its effects on key enzymatic activities in insect physiology, remain insufficiently understood. In this study, a combination of experimental measurements and molecular dynamics (MD) simulations was employed to investigate the regulatory effects of electric field treatment on acetylcholinesterase (AChE) activity in Sitophilus oryzae and its underlying molecular mechanisms. Experimentally, different electric field parameters were applied to assess insect mortality and AChE activity changes. Meanwhile, MD simulations were performed to elucidate the structural dynamics of AChE under electric field exposure, revealing its activity regulation mechanism. The results demonstrated that electric field treatment disrupted the structural stability of AChE, leading to alterations in its active site and consequently reducing its catalytic activity. Specifically, under a 0.5 V/nm electric field, the solvent-accessible surface area of AChE increased by 47.2%, the number of backbone hydrogen bonds decreased by 13.2%, and the α-helix and β-sheet contents were reduced by 28.3% and 25%, respectively. This study elucidates the structural and functional regulatory mechanisms of AChE under electric field exposure, providing theoretical insights into the application of electro pest control technology in agricultural pest management.