title: Trifluoroethanol-induced conformational transition of hen egg-white lysozyme studied by small-angle X-ray scattering.
abstract: The trifluoroethanol (TFE)-induced conformational transition of hen lysozyme was studied with the combined use of far-UV circular dichroism (CD) and small-angle X-ray scattering. At pH 2.0 and 20 degrees C, the addition of TFE to the native lysozyme induced a cooperative transition to an intermediate state with an increased helical content (TFE state). Small-angle X-ray scattering measurements indicated that the TFE state has a radius of gyration which is 20% larger than that of the native state and assumes a chain-like conformation with some remaining globularity. The TFE-induced transition curves obtained by CD and the small-angle X-ray scattering measurements agreed well, consistent with a two-state transition mechanism. A singular value decomposition analysis of Kratky plots of the small-angle X-ray scattering profiles indicated that two basic scattering functions reproduce the observed spectra, further confirming the validity of a two-state approximation.
authors.affiliation: Department of Biology, Graduate School of Science, Osaka University, Toyonaka, Japan.
authors.forename: M
authors.initials: M
authors.lastname: Hoshino
authors.forename: Y
authors.initials: Y
authors.lastname: Hagihara
authors.forename: D
authors.initials: D
authors.lastname: Hamada
authors.forename: M
authors.initials: M
authors.lastname: Kataoka
authors.forename: Y
authors.initials: Y
authors.lastname: Goto
mesh_terms: D000818:Animals; D002645:Chickens; D002942:Circular Dichroism; D004529:Egg White; D005260:Female; D009113:Muramidase / Q000737:chemistry*; D011487:Protein Conformation; D012542:Scattering, Radiation; D013056:Spectrophotometry, Ultraviolet; D013816:Thermodynamics; D014270:Trifluoroethanol / Q000737:chemistry*
chemical_list: D014270:Trifluoroethanol; D009113:Muramidase