title: Ion specific protein assembly and hydrophobic surface forces.
abstract: Large anions are attracted to hydrophobic surfaces while smaller, well solvated ions are repelled. Using a combination of explicit solvent and continuum model simulations we show that this leads to significant ion-specific protein-protein interactions due to hydrophobic patches on the protein surfaces. In solutions of NaI and NaCl we calculate the potentials of mean force and find that the resulting second virial coefficients for lysozyme correspond well with experiment. We argue that ionic interactions with nonpolar surface groups may play an important role for biomolecular assembly and Hofmeister-type effects.
authors.affiliation: Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic. mikael.lund@uochb.cas.cz
authors.forename: Mikael
authors.initials: M
authors.lastname: Lund
authors.forename: Pavel
authors.initials: P
authors.lastname: Jungwirth
authors.forename: Clifford E
authors.initials: CE
authors.lastname: Woodward
mesh_terms: D003198:Computer Simulation; D006863:Hydrogen-Ion Concentration; D057927:Hydrophobic and Hydrophilic Interactions; D007477:Ions / Q000737:chemistry; D008956:Models, Chemical; D008958:Models, Molecular; D009010:Monte Carlo Method; D009113:Muramidase / Q000737:chemistry*; D012965:Sodium Chloride / Q000737:chemistry; D012974:Sodium Iodide / Q000737:chemistry; D012996:Solutions; D055672:Static Electricity; D013499:Surface Properties
chemical_list: D007477:Ions; D012996:Solutions; D012965:Sodium Chloride; D009113:Muramidase; D012974:Sodium Iodide