A Tale of Two Desolvation Potentials: An Investigation of Protein Behavior Under High Hydrostatic Pressure

Abstract

Hydrostatic pressure is a common perturbation to probe the conformations of proteins. There are two common forms of pressure dependent potentials of mean force (PMFs) derived from hydrophobic molecules available for the coarse grained molecular simulations of protein folding and unfolding under hydrostatic pressure. Although both PMF includes a desolvation barrier separating the well of a direct contact and the well of a solvent mediated contact, how these features vary with hydrostatic pressure is still debated. There is a need of a systematic comparison of these two PMFs on a protein. We investigated the two different pressure dependencies on the desolvation potential in a structure based protein model using coarse grained molecular simulations. We compared them to the known behavior a real protein based on experimental evidence. We showed that the protein s folding transition curve on the pressure temperature phase diagram depends on the relationship between the potential well minima and pressure. For protein that reduces the total volume under pressure, it is essential for the PMF to carry the feature that the direct contact well is essential less stable than the water mediated contact well at high pressure. We also comment on the practicality and importance of structure based minimalist models for understanding the phenomenological behavior of a protein under a wide range of phase space.

arXiv comment6 figures

References in corpus (8)

• Statistical mechanics for natural flocks of birds
• Protein folding mediated by solvation: water expelling and formation of the hydrophobic core occurs after the structure collapse
• Origin of entropy convergence in hydrophobic hydration and protein folding
• Microscopic mechanism for cold denaturation
• Contribution of Water to Pressure and Cold Denaturation of Proteins
• Consistent treatment of hydrophobicity in protein lattice models accounts for cold denaturation
• Critical phenomena in the temperature-pressure-crowding phase diagram of a protein
• Role of solvation in pressure-induced helix stabilization