title: NMR studies of an FK-506 analog, [U-13C]ascomycin, bound to FK-506-binding protein.
abstract: Multidimensional, heteronuclear NMR methods were used to determine the complete 1H and 13C resonance assignments for [U-13C]ascomycin bound to recombinant FKBP, including stereospecific assignment of all 22 methylene protons. The conformation of ascomycin was then determined from an analysis of NOEs observed in a 13C-edited 3D HMQC-NOESY spectrum of the [U-13C]ascomycin/FKBP. This structure is found to be quite different from the solution structure of the two forms of uncomplexed FK-506. However, it is very similar to the X-ray crystal structure of FK-506 bound to FKBP, rms deviation = 0.56 A. The methods used for resonance assignment and structure calculation are presented in detail. Furthermore, FKBP/ascomycin NOEs are reported which help define the structure of the ascomycin binding pocket. This structural information obtained in solution was compared to the recently described X-ray crystal structure of the FKBP/FK-506 complex.
authors.affiliation: Pharmaceutical Discovery Division, Abbott Park, Illinois 60064.
authors.forename: A M
authors.initials: AM
authors.lastname: Petros
authors.forename: G
authors.initials: G
authors.lastname: Gemmecker
authors.forename: P
authors.initials: P
authors.lastname: Neri
authors.forename: E T
authors.initials: ET
authors.lastname: Olejniczak
authors.forename: D
authors.initials: D
authors.lastname: Nettesheim
authors.forename: R X
authors.initials: RX
authors.lastname: Xu
authors.forename: E G
authors.initials: EG
authors.lastname: Gubbins
authors.forename: H
authors.initials: H
authors.lastname: Smith
authors.forename: S W
authors.initials: SW
authors.lastname: Fesik
mesh_terms: D002247:Carbon Isotopes; D002352:Carrier Proteins / Q000235:genetics / Q000378:metabolism*; D002460:Cell Line; D004926:Escherichia coli / Q000235:genetics; D015870:Gene Expression; D005798:Genes, Bacterial; D006801:Humans; D009682:Magnetic Resonance Spectroscopy; D011994:Recombinant Proteins / Q000235:genetics / Q000378:metabolism; D013601:T-Lymphocytes / Q000378:metabolism; D016559:Tacrolimus / Q000031:analogs & derivatives* / Q000737:chemistry / Q000378:metabolism; D022021:Tacrolimus Binding Proteins; D014961:X-Ray Diffraction
chemical_list: D002247:Carbon Isotopes; D002352:Carrier Proteins; D011994:Recombinant Proteins; C058028:immunomycin; D022021:Tacrolimus Binding Proteins; D016559:Tacrolimus