The surface exposed amino acid residues of monomeric proteins determine the partitioning in aqueous two-phase systems

Investigation of protein retention and selectivity in HIC systems using quantitative structure retention relationship models

“…Based on the concept that the overall surface hydrophobicity of a molecule can be obtained as a superposition of surface fragment contributions, two methodologies proposed by Berggren et al (2002) to evaluate protein behavior in aqueous two-phase systems (ATPSs) were employed to evaluate the surface hydrophobicity of proteins. The surface hydrophobicity H surface for a given protein is defined as:…”

Identification of the roles of conserved charged residues in the extracellular domain of an epithelial sodium channel (ENaC) subunit by alanine mutagenesis

“…Charged residues in proteins may have diverse roles including enhancing the hydrophilicity of the protein in an aqueous environment (4,42), participation in the formation of intra-and intermolecular salt bridges between residues carrying opposite charges (e.g., Asp ↔ Arg) in interacting segments of proteins (19,23,27) and specific binding of ions during the course of ion movement in channels (20,35,40). Specifically in ␣-ENaC, charged residues have been shown to be essential for recognition by specific proteases that activate ENaC (18), and histidine residues in ECD have been shown to affect Na ϩ dependent self-inhibition of ENaC (32).…”

Hydrophobic Interaction Chromatography: Fundamentals and Applications in Biomedical Engineering

“…The classical approach consists of estimating the "average surface hydrophobicity" (φ surface ) based on the three-dimensional structure of the macromolecule in its native conformation (Lienqueo et al, 2002;Berggren et al, 2002). This approach considers only the amino acid residues that are accessible to the solvent at the protein surface, by using three-dimensional structural data.…”