title: Crystal structure of recombinant human T-cell cyclophilin A at 2.5 A resolution.
abstract: The structure of the unligated human T-cell recombinant cyclophilin has been determined at 3 A resolution by multipole isomorphous replacement methods and refined at 2.5 A resolution to an R factor of 0.209. The root-mean-square errors of the bond lengths and bond angles are 0.013 A and 2.8 degrees from ideal geometry, respectively. The overall structure is a beta-barrel, consisting of eight antiparallel beta-strands wrapping around the barrel surface and two alpha-helices sitting on the top and the bottom closing the barrel. Inside the barrel, seven aromatic and other hydrophobic residues form a compact hydrophobic core. A loop of Lys-118 to His-126 and four beta-strands (B3-B6) constitute a pocket we speculate to be the binding site of cyclosporin A.
authors.affiliation: Department of Biochemistry and Biophysics, University of North Carolina, Chapel Hill 27599.
authors.forename: H M
authors.initials: HM
authors.lastname: Ke
authors.forename: L D
authors.initials: LD
authors.lastname: Zydowsky
authors.forename: J
authors.initials: J
authors.lastname: Liu
authors.forename: C T
authors.initials: CT
authors.lastname: Walsh
mesh_terms: D000591:Amino Acid Isomerases / Q000737:chemistry*; D000595:Amino Acid Sequence; D001665:Binding Sites; D002352:Carrier Proteins / Q000737:chemistry*; D003196:Computer Graphics; D003461:Crystallography; D016572:Cyclosporine / Q000378:metabolism; D006801:Humans; D008969:Molecular Sequence Data; D019696:Peptidylprolyl Isomerase; D011487:Protein Conformation; D011994:Recombinant Proteins / Q000737:chemistry; D016415:Sequence Alignment; D012995:Solubility; D014961:X-Ray Diffraction
chemical_list: D002352:Carrier Proteins; D011994:Recombinant Proteins; D016572:Cyclosporine; D000591:Amino Acid Isomerases; D019696:Peptidylprolyl Isomerase