###### Abstract  
Our present study concerns the influence of the picosecond rise-time-pulsed electromagnetic field, and the impact of nanosecond pulsed pressure on the aggregation state of horseradishis peroxidase (HRP) as a model enzyme. The influence of a 640 kV/m pulsed electromagnetic field with a pulse rise-time of \(\sim\)200 ps on the activity and aggregation state of an enzyme is studied by the single-molecule atomic force microscopy (AFM) method. The influence of such a field is shown to lead to aggregation of the protein and to a decrease in its enzymatic activity. Moreover, the effect of a shock wave with a pressure front rise-time of 80 ns on the increase in the HRP aggregation is demonstrated. The results obtained herein can be of use in modeling the impact of electromagnetic and pressure pulses on enzymes and on whole living organisms. Our results are also important for taking into account the effect of pulsed fields on the body in the development of drugs, therapeutic procedures, and novel highly sensitive medical diagnostics. Keywords:horseradishis peroxidase; atomic force microscopy; protein aggregation; shock wave; pulsed electromagnetic field +
Footnote †: journal:  
Article  
The Impact of Fast-Rise-Time Electromagnetic Field and Pressure on the Aggregation of Peroxidase upon Its Adsorption onto [PERSON], [PERSON], V.  
proper functioning of the body; for instance, myeloperoxidase functions in dimeric form [8], formed by functionally independent monomeric units joined by a single disulfide bond at Cys153 [9]. Another example is glutathione peroxidase, which participates in oxidative stress regulation and is functionally active in tetrameric form [10]. The negative effect of protein aggregation manifests itself in the form of the development of various pathologies in the body caused by the formation of protein aggregates. Namely, protein aggregation is known to be a cause of cardiovascular diseases [11]. Furthermore, protein aggregation was reported to be associated with cancer in humans: [PERSON] et al. [12] reported that aggregation processes, which involve mutant p53 protein, are associated with the development of cancer, which could thus be considered as aggregation-associated disease. This was confirmed in the research performed by other authors [13; 14; 15]. Another well-known fact is that the formation of amyloid aggregates in the brain was considered to lead to [PERSON]'s [16] and Alzheimer's [16; 17; 18] diseases. In this connection, it should be, however, emphasized that certain proteins in amyloid form are relevant for proper brain functioning: therefore, in mammals' brain, FXR1 protein, which regulates memory and emotions, is functioning in amyloid form [16]. Medicial agents, intended for the treatment of diseases caused by protein aggregation, are often non-specifically disrupting the protein aggregates. During such a non-specific therapy, however, not only the target pathology-associated protein aggregates but also the ones required for proper body functioning, can be destroyed. In this connection, the revelation and investigation of factors influencing protein aggregation, the development of methods for the assessment of this influence, and the development of novel approaches providing specific correction of protein aggregation, represent important tasks of modern biomedical research aimed at maintaining human health. Regarding magnetic (MFs) and electromagnetic fields (EMFs), a lot of attention is given to these fields with relatively long rise-times. Both extremely low frequency (20 to 75 Hz [1, 19; 20; 21]) and microwave frequency EMFs [22; 23; 24] are known to influence protein structure and/or functionality. Regarding protein structure changes, irradiation in 940 MHz circularly polarized EMF was shown to cause partial unfolding of adult hemoglobin [22]. [PERSON] et al. [23] reported that 0.5 h-long microwave irradiation (at a temperature of 60 \({}^{\circ}\)C and radiation power of 60 W) of horseradish peroxidase leads to significant (-80%) loss in its enzymatic activity.