Theory for the aggregation of proteins and copolymers

摘要: We develop mean-field lattice statistical mechanics theory for the equilibrium between denatured and aggregated states of proteins other random copolymers hydrophobic polar monomers in aqueous solution. suppose that state is a mixture amorphous polymer plus solvent driving forces are interaction, which favors aggregation, conformational translational entropies, favor disaggregation. The predicts phase diagram thermal aggregation an asymmetric closed loop, denaturants (guanidinium hydrochloride urea) it with upper consolute point. copolymer poor will expand increasing concentration because {open_quotes}screening{close_quotes} interactions by chains; chain ultimately reaches theta-like absence solvent. screening depends strongly on composition. find two striking features these diagrams. First, they extraordinarily sensitive to composition; change one amino acid can substantially behavior. Second, relative homopolymers, should be stable against at concentrations higher many orders magnitude. 43 refs., 13 figs.