title: NH exchange in point mutants of human ubiquitin.
abstract: Several point mutants of human ubiquitin (Ub(T9V), Ub(F45W), Ub(F45G), and Ub(A46S)) were prepared by recombinant techniques. The NH exchange rate constants were measured by the NMR diffusion and the MEXICO methods and compared with those in the wild type to examine the influence of structural changes and to improve the understanding of this important reaction in studies of protein folding and denaturation. The observed changes follow qualitatively the polarity and steric alterations caused by the introduced amino acids. Attempts to reproduce quantitatively the observed changes by modeling studies and molecular dynamics simulations were not satisfactory.
authors.affiliation: Institute of Analytical Chemistry, University of Leipzig, Leipzig, Germany.
authors.forename: Nicole
authors.initials: N
authors.lastname: Jahr
authors.forename: Erik
authors.initials: E
authors.lastname: Fiedler
authors.forename: Robert
authors.initials: R
authors.lastname: Günther
authors.forename: Hans-Jörg
authors.initials: HJ
authors.lastname: Hofmann
authors.forename: Stefan
authors.initials: S
authors.lastname: Berger
mesh_terms: D000595:Amino Acid Sequence; D019295:Computational Biology; D006801:Humans; D050505:Mutant Proteins / Q000737:chemistry* / Q000235:genetics*; D017354:Point Mutation / Q000235:genetics*; D016415:Sequence Alignment; D025801:Ubiquitin / Q000737:chemistry* / Q000235:genetics*
chemical_list: D050505:Mutant Proteins; D025801:Ubiquitin