title: Motional properties of unfolded ubiquitin: a model for a random coil protein.
abstract: The characterization of unfolded states of proteins has recently attracted considerable interest, as the residual structure present in these states may play a crucial role in determining their folding and misfolding behavior. Here, we investigated the dynamics in the denatured state of ubiquitin in 8 M urea at pH2. Under these conditions, ubiquitin does not have any detectable local residual structure, and uniform 15N relaxation rates along the sequence indicate the absence of motional restrictions caused by residual secondary structure and/or long-range interactions. A comparison of different models to predict relaxation data in unfolded proteins suggests that the subnanosecond dynamics in unfolded states depend on segmental motions only and do not show a dependence on the residue type but for proline and glycine residues.
authors.affiliation: Institute for Organic Chemistry and Chemical Biology, Center for Biomolecular Magnetic Resonance, Johann Wolfgang Goethe University Frankfurt, Marie-Curie-Str. 11, D-60439, Frankfurt, Germany.
authors.forename: Julia
authors.initials: J
authors.lastname: Wirmer
authors.forename: Wolfgang
authors.initials: W
authors.lastname: Peti
authors.forename: Harald
authors.initials: H
authors.lastname: Schwalbe
mesh_terms: D006863:Hydrogen-Ion Concentration; D057927:Hydrophobic and Hydrophilic Interactions; D008958:Models, Molecular; D019906:Nuclear Magnetic Resonance, Biomolecular; D011489:Protein Denaturation; D017510:Protein Folding; D017433:Protein Structure, Secondary; D011506:Proteins / Q000737:chemistry*; D025801:Ubiquitin / Q000737:chemistry*; D014508:Urea / Q000737:chemistry
chemical_list: D011506:Proteins; D025801:Ubiquitin; D014508:Urea