Local Heterogeneous Domains Drive Stability of Proteins in Non-Aqueous Solution*

Local heterogeneous environment provide much richer phenomena than homogeneous solutions. For instance, our recent work reveals the presence of finger-shaped water channels at water-oil interface, which facilitate ion transport.¹ Another example is the hydrophilic and hydrophobic patches covering the surface of globular proteins. In the present work, the influences of these surface heterogeneous domains are quantified in stabilizing the structures and activities of proteins in organic solvent with the assistance of amphiphilic random heteropolymers. By means of all-atom, explicit solvent molecular dynamics simulations we quantify the adsorption of the random copolymer surfactant onto the hydrophilic patches of the protein surface. The protein-polymer complex forms a giant core-shell structure dissolved in organic solution. This work thus shed significant insights for the remarkable impacts of small-size heterogeneous domains.

[1] Qiao, B.; Muntean, J. V.; Olvera de la Cruz, M.; Ellis, R. J., Langmuir 2017, 33 (24), 6135-6142.