title: NMR determination of residual structure in a urea-denatured protein, the 434-repressor.
abstract: A nuclear magnetic resonance (NMR) structure determination is reported for the polypeptide chain of a globular protein in strongly denaturing solution. Nuclear Overhauser effect (NOE) measurements with a 7 molar urea solution of the amino-terminal 63-residue domain of the 434-repressor and distance geometry calculations showed that the polypeptide segment 54 to 59 forms a hydrophobic cluster containing the side chains of Val54, Val56, Trp58, and Leu59. This residual structure in the urea-unfolded protein is related to the corresponding region of the native, folded protein by simple rearrangements of the residues 58 to 60. Based on these observations a model for the early phase of refolding of the 434-repressor(1-63) is proposed.
authors.affiliation: Institut für Molekularbiologie und Biophysik, ETH-Hönggerberg, Zürich, Switzerland.
authors.forename: D
authors.initials: D
authors.lastname: Neri
authors.forename: M
authors.initials: M
authors.lastname: Billeter
authors.forename: G
authors.initials: G
authors.lastname: Wider
authors.forename: K
authors.initials: K
authors.lastname: Wüthrich
mesh_terms: D000595:Amino Acid Sequence; D009682:Magnetic Resonance Spectroscopy / Q000379:methods; D008958:Models, Molecular; D008969:Molecular Sequence Data; D011487:Protein Conformation; D011489:Protein Denaturation; D012097:Repressor Proteins / Q000737:chemistry* / Q000494:pharmacology; D014508:Urea / Q000494:pharmacology*; D014764:Viral Proteins
chemical_list: C063367:434-repressor protein, Bacteriophage 434; D012097:Repressor Proteins; D014764:Viral Proteins; D014508:Urea