# Incubation of Horseradish Peroxidase near 50 Hz AC Equipment Promotes Its Disaggregation and Enzymatic Activity

## TL;DR

Exposure of horseradish peroxidase to low-frequency electromagnetic fields from AC equipment increases its activity and changes its structure.

## Contribution

The study reveals that incubation near a 50 Hz AC autotransformer enhances HRP activity and promotes monomer adsorption.

## Key findings

- Incubation near a loaded autotransformer increased HRP monomer adsorption on mica by two orders of magnitude.
- HRP incubated above a switched-off transformer also showed disaggregation and increased activity.
- Exposure to low-frequency electromagnetic fields may influence enzyme function and require proper shielding.

## Abstract

Low-frequency electromagnetic fields, induced by alternating current (AC)-based equipment such as transformers, are known to influence the physicochemical properties and function of enzymes, including their catalytic activity. Herein, we have investigated how incubation near a 50 Hz AC autotransformer influences the physicochemical properties of horseradish peroxidase (HRP), by atomic force microscopy (AFM) and spectrophotometry. We found that a half-hour-long incubation of the enzyme above the coil of a loaded autotransformer promoted the adsorption of the monomeric form of HRP on mica, enhancing the number of adsorbed enzyme particles by two orders of magnitude in comparison with the control sample. Most interestingly, the incubation of HRP above the switched-off transformer, which was unplugged from the mains power supply, for the same period of time was also found to cause a disaggregation of the enzyme. Notably, an increase in the activity of HRP against ABTS was observed in both cases. We hope that the interesting effects reported will emphasize the importance of consideration of the influence of low-frequency electromagnetic fields on enzymes in the design of laboratory and industrial equipment intended for operation with enzyme systems. The effects revealed in our study indicate the importance of proper shielding of AC-based transformers in order to avoid the undesirable influence of low-frequency electromagnetic fields induced by these transformers on humans.