title: Molten-globule conformation of Arc repressor monomers determined by high-pressure 1H NMR spectroscopy.
abstract: The conformation of the pressure-dissociated monomer of Arc repressor was characterized by 1H NMR spectroscopy. The NMR spectra of the monomer under pressure (up to 5.0 kbar; 1 bar = 100 kPa) are typical of a molten globule and they are considerably different from those of the native dimer and thermally denatured monomer. The two-dimensional nuclear Overhauser effect spectra suggest that the pressure-induced molten globule retains some secondary structure. The presence of nuclear Overhauser effects in the beta-sheet region in the dissociated state suggests that the intermonomer beta-sheet (residues 8-14) in the native dimer is replaced by an intramonomer beta-sheet. Changes in one-dimensional and two-dimensional NMR spectra prior to pressure dissociation were found and suggest the existence of a "predissociated" state.
authors.affiliation: Department of Chemistry, School of Chemical Sciences, University of Illinois, Urbana 61801.
authors.forename: X
authors.initials: X
authors.lastname: Peng
authors.forename: J
authors.initials: J
authors.lastname: Jonas
authors.forename: J L
authors.initials: JL
authors.lastname: Silva
mesh_terms: D000595:Amino Acid Sequence; D004268:DNA-Binding Proteins / Q000737:chemistry*; D006874:Hydrostatic Pressure; D009682:Magnetic Resonance Spectroscopy; D008969:Molecular Sequence Data; D011487:Protein Conformation; D011489:Protein Denaturation; D017433:Protein Structure, Secondary; D011994:Recombinant Proteins; D012097:Repressor Proteins / Q000737:chemistry*; D014764:Viral Proteins / Q000737:chemistry*; D054334:Viral Regulatory and Accessory Proteins
chemical_list: D004268:DNA-Binding Proteins; D011994:Recombinant Proteins; D012097:Repressor Proteins; D014764:Viral Proteins; D054334:Viral Regulatory and Accessory Proteins; C016649:phage repressor proteins