title: Solution structure of the active domain of tissue inhibitor of metalloproteinases-2. A new member of the OB fold protein family.
abstract: Homonuclear two-dimensional and three-dimensional 1H nuclear magnetic resonance spectroscopy has been used to obtain essentially complete sequence-specific assignments for 123 of the 127 amino acid residues present in the truncated form of tissue inhibitor of metalloproteinases-2 (delta TIMP-2), the active N-terminal domain of the protein. Analysis of the through-space nuclear Overhauser effect data obtained for delta TIMP-2 allowed determination of both the secondary structure of the domain and also a low-resolution tertiary structure defining the protein backbone topology. The protein contains a five-stranded antiparallel beta-sheet that is rolled over on itself to form a closed beta-barrel, and two short helices which pack close to one another on the same barrel face. A comparison of the delta TIMP-2 structure with other known protein folds reveals that the beta-barrel topology is homologous to that seen in proteins of the oligosaccharide/oligonucleotide binding (OB) fold family. The common structural features include the number of beta-strands and their arrangement, the beta-barrel shear number, an interstrand hydrogen bond network, the packing of the hydrophobic core, and a conserved beta-bulge. Superpositions of the beta-barrels from delta TIMP-2 and two previously known members of the OB protein fold family (staphylococcal nuclease and Escherichia coli heat-labile enterotoxin) confirmed the similarity in beta-barrel topology. The three-dimensional structure of delta TIMP-2 has allowed a more detailed interpretation than was previously possible of the functional significance of available protein sequence and site-directed mutagenesis data for the TIMP family. Furthermore, the structure has revealed conserved surface regions of potential functional importance.
authors.affiliation: Research School of Biosciences, Biological Laboratory, University of Kent, Canterbury, U.K.
authors.forename: R A
authors.initials: RA
authors.lastname: Williamson
authors.forename: G
authors.initials: G
authors.lastname: Martorell
authors.forename: M D
authors.initials: MD
authors.lastname: Carr
authors.forename: G
authors.initials: G
authors.lastname: Murphy
authors.forename: A J
authors.initials: AJ
authors.lastname: Docherty
authors.forename: R B
authors.initials: RB
authors.lastname: Freedman
authors.forename: J
authors.initials: J
authors.lastname: Feeney
mesh_terms: D000595:Amino Acid Sequence; D001665:Binding Sites; D009682:Magnetic Resonance Spectroscopy / Q000379:methods; D008666:Metalloendopeptidases / Q000037:antagonists & inhibitors; D008958:Models, Molecular; D008969:Molecular Sequence Data; D010446:Peptide Fragments / Q000737:chemistry*; D011487:Protein Conformation; D017433:Protein Structure, Secondary; D011506:Proteins / Q000737:chemistry* / Q000145:classification; D011994:Recombinant Proteins / Q000737:chemistry; D017386:Sequence Homology, Amino Acid; D012996:Solutions / Q000737:chemistry; D019716:Tissue Inhibitor of Metalloproteinase-2
chemical_list: D010446:Peptide Fragments; D011506:Proteins; D011994:Recombinant Proteins; D012996:Solutions; D019716:Tissue Inhibitor of Metalloproteinase-2; D008666:Metalloendopeptidases