Frequency Dependent Non- Thermal Effects of Oscillating Electric Fields in the Microwave Region on the Properties of a Solvated Lysozyme System: A Molecular Dynamics Study

PLoS One. 2017 Jan 27;12(1):e0169505. doi: 10.1371/journal.pone.0169505. eCollection 2017.

Abstract

The use of microwaves in every day's applications raises issues regarding the non thermal biological effects of microwaves. In this work we employ molecular dynamics simulations to advance further the dielectric studies of protein solutions in the case of lysozyme, taking into consideration possible frequency dependent changes in the structural and dynamic properties of the system upon application of electric field in the microwave region. The obtained dielectric spectra are identical with those derived in our previous work using the Fröhlich-Kirkwood approach in the framework of the linear response theory. Noticeable structural changes in the protein have been observed only at frequencies near its absorption maximum. Concerning Cα position fluctuations, different frequencies affected different regions of the protein sequence. Furthermore, the influence of the field on the kinetics of protein-water as well as on the water-water hydrogen bonds in the first hydration shell has been studied; an extension of the Luzar-Chandler kinetic model was deemed necessary for a better fit of the applied field results and for the estimation of more accurate hydrogen bond lifetime values.

MeSH terms

  • Amino Acid Sequence / radiation effects
  • Dielectric Spectroscopy
  • Humans
  • Hydrogen Bonding / radiation effects
  • Kinetics
  • Microwaves / adverse effects*
  • Molecular Dynamics Simulation*
  • Muramidase / chemistry*
  • Muramidase / radiation effects
  • Water / chemistry*

Substances

  • Water
  • Muramidase

Grants and funding

This work has been financially supported partly by the postgraduate courses of the Department of Biochemistry & Biotechnology “Biotechnology - Quality Assessment in Nutrition and the Environment” (Funding number 3439) and “Applications of Molecular Biology - Genetics - Diagnostic Biomarkers” (Funding number 3817). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.