Liquid-liquid phase separation and intermolecular interactions in dense protein solutions

摘要

Highly concentrated protein solution were found to yield a large number of different phases, like amorphous aggregates, gels, crystals, or a liquid-liquid phase separation, which are all governed by the underlying protein-protein interactions in water. The interactions in dense protein solutions are highly complex, changes in the aqueous environment influence the inter- and intramolecular interactions, the protein-solvent interactions, and the solvent-solvent interactions. In this thesis, small angle X-ray scattering in combination with hydrostatic pressure perturbation was used to investigate the intermolecular interaction potential and the resulting phase behavior of dense lysozyme solutions. A reentrant liquid-liquid phase separation at elevated pressures was discovered, which could be ascribed to the solvent mediated protein-protein interactions.