EPJ D Highlight - Deeper insights into protein folding

Figure 2 (a) from the original paper Caption: “Structure of staphylococcal nuclease.” © Yakubovich et al.

Physicists have published a new theoretical foundation explaining the mechanism of protein folding and unfolding in water

Investigating the structure and dynamics of so-called Meso-Bio-Nano (MBN) systems—micron-sized biological or nanotechnology entities—is a rapidly expanding field of science. Now, scientists Alexander Yakubovich and Andrey Solov'yov from MBN Research Centre in Frankfurt, Germany, have produced a new theoretical study of a protein macromolecules changing from a coil structural conformation to a globular one. Their statistic mechanics model, just published in EPJ D, describes the thermodynamic properties of real proteins in an aqueous environment, using a minimal number of free physical parameters.

In this work, the authors confirmed the validity of their theoretical calculation of dependencies of the protein heat capacities on temperature by comparing it with the corresponding experimental measurements for two proteins, namely an enzyme called staphylococcal nuclease and an oxygen and iron carrier protein called metmyoglobin. Sudden changes in temperature could result in the loss of a protein’s three-dimensional structure and function. Thus, these findings could contribute to our understanding of high-energy ions therapy on biological cells.

The authors also focus on the folding and unfolding of globular proteins at various levels of temperature in an aqueous environment. Their statistical mechanics model is inspired by a pre-existing model of solvation of hydrophobic hydrocarbons. This leads to establishing the so-called partition function of this globular protein in water environment. In turn, this helps to determine all of the protein’s thermodynamic characteristics at equilibrium. These include its heat capacity and the average number of amino acids in an unfolded conformation.

The study validates the use of an approximation of three stages of macromolecular complexes undergoing folding and unfolding transformations, instead of using fitting parameters as previously done. These results also significantly expand the possibilities of quantitative description of the structure conformation processes for other proteins obeying simple folding kinetics and complex multi-domain proteins with peculiar folding profiles.

As Editors of the volume 108 of EPJ Web of Conferences, we ask you personally to accept our deep gratitude. It was a great favour to work with you and the EPJ Web of Conferences team on all stages involved in the publication of the post-processed Proceedings of MMCP 2015. We have been very satisfied with your courteous consideration of every our demand, without exception, with your contribution to finding the most convenient outcomes. Your determination to speed up the publishing process is highly appreciated.

George Adam, JINR Dubna, Russia
Michal Hnatic, Institute of Experimental Physics, Slovak Republic
Ján Buša, Technical University of Kosice, Slovak Republic
Co-editors of MMCP 2015, EPJ Web of Conferences vol. 108, 2016

ISSN: 2100-014X (Electronic Edition)

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