title: Protein folding and aggregation studied by isoelectric focusing across a urea gradient and isoelectric focusing in two dimensions.
abstract: Isoelectric focusing across a concentration gradient of urea was used to study the folding-unfolding and association-dissociation processes of proteins. Myoglobulin, albumin, RNase, papain, beta L- and alpha-crystallin were analyzed with this technique, and examples are given of visualized dissociation steps and of equilibrium-unfolding intermediates. Furthermore, a two-dimensional isoelectric focusing technique is presented that is useful to deduce whether a transition of a protein aggregate observed upon urea-gradient isoelectric focusing must be attributed to a change in the protein's tertiary or quaternary structure.
authors.affiliation: Department of Biochemistry, University of Nijmegen, The Netherlands.
authors.forename: P J
authors.initials: PJ
authors.lastname: van den Oetelaar
authors.forename: B M
authors.initials: BM
authors.lastname: de Man
authors.forename: H J
authors.initials: HJ
authors.lastname: Hoenders
mesh_terms: D000818:Animals; D003459:Crystallins; D006736:Horses; D006801:Humans; D007074:Immunoglobulin G; D007525:Isoelectric Focusing / Q000379:methods*; D009211:Myoglobin; D010206:Papain; D011485:Protein Binding; D011487:Protein Conformation; D011489:Protein Denaturation / Q000187:drug effects; D012709:Serum Albumin; D014508:Urea / Q000494:pharmacology
chemical_list: D003459:Crystallins; D007074:Immunoglobulin G; D009211:Myoglobin; D012709:Serum Albumin; D014508:Urea; D010206:Papain