title: Comparison of solution structure of free and complexed lac operator by molecular modelling with NMR constraints.
abstract: The structure difference between the free operator of the lac system d(GCTCACAAT).d(ATTGTGAGC) and the same operator complexed to the headpiece of the lac repressor has been investigated by 2-D-1H NMR spectroscopy in conjunction with molecular modelling in internal coordinates (JUMNA). The free and complexed operator adopt both a right-handed B helical conformation, but a more detailed analysis of the conformational parameters using the Curves program shows striking differences in the groove geometries, the rises, the twists and the total bending.
authors.affiliation: CBM-CNRS, Orléans, France.
authors.forename: E
authors.initials: E
authors.lastname: Gincel
authors.forename: G
authors.initials: G
authors.lastname: Lancelot
authors.forename: J C
authors.initials: JC
authors.lastname: Maurizot
authors.forename: N T
authors.initials: NT
authors.lastname: Thuong
authors.forename: F
authors.initials: F
authors.lastname: Vovelle
mesh_terms: D001483:Base Sequence; D004926:Escherichia coli / Q000235:genetics; D007763:Lac Operon; D007786:Lactose Factors / Q000737:chemistry*; D009682:Magnetic Resonance Spectroscopy; D008958:Models, Molecular; D008969:Molecular Sequence Data; D012097:Repressor Proteins / Q000737:chemistry*
chemical_list: D012097:Repressor Proteins