High throughput characterization of structural differences between closely related proteins in solution

Partitioning of a protein in an aqueous two-phase system (ATPS) is governed by interactions of the protein with aqueous media in the two phases. Here we describe how partitioning of proteins in a set of ATPS of different compositions can be used to quantify differences between 3D structures of closely related proteins. We also provide perspective on practical applications of the technology when comparative analysis of the higher-order structure of proteins is desired. [Display omitted] ► Distinguishing protein isoforms without detailed structural analysis is often needed. ► Analytical tool exploiting isoform differences in solvent interaction is introduced. ► This technique is based on the protein partition in aqueous two-phase systems (ATPS). ► ATPS generate very crowded environment. ► Macromolecular crowding conditions of ATPS amplify structural differences of isoforms.