Folding/unfolding of protein Trp cage in aqueous osmolyte solutions under polar confinement

摘要

Folding/unfolding processes of the protein Trp cage in presence of osmolytes inside a polar confinement is investigated using replica exchange molecular dynamics (REMD) simulation. A near spherical fullerene like ball consisting of 2940 carbon atoms (charged atoms) is used as a polar confinement. Urea exerts its action profoundly on the protein causing denaturation. Counteraction of TMAO is also observed in ternary solution of urea and TMAO. It is found that TMAO exerts its action in ternary mixed urea-TMAO solution by (i) removing some of the urea-TMAO hydrogen bonds, (ii) preserving the angles and distances between the aromatic planes of the residues Pro17, Prol 8 and Prol9 with the indole ring of Trp6 and (iii) retaining the hydrophobic core of the protein Trp cage. (C) 2017 Elsevier B.V. All rights reserved.