title: Identification and description of beta-structure in horse muscle acylphosphatase by nuclear magnetic resonance spectroscopy.
abstract: Nuclear magnetic resonance spectra of acylphosphatase were searched for signs of beta-structure, i.e. characteristic nuclear Overhauser enhancement patterns displayed in the two-dimensional spectra, typical chemical shifts, coupling constants and slow 2H-H exchange. The results provided identification of the main-chain resonances of amino acid residues involved in the beta-structure. The full sequential assignment of this region was gained by identification of some amino acid spin systems and their alignment with the primary sequence. The assignment of the side-chains was virtually completed subsequently and a list produced of nuclear magnetic resonance (n.m.r.) constraints derived from the spectra. The beta-structure consists of a beta-sheet with four antiparallel chains, one attached parallel chain, three tight turns and a beta-bulge. The conformation of the beta-sheet was determined by distance geometry calculation using the n.m.r. constraints (174 intraresidual, 107 sequential and 226 long-range distances, 32 torsion angles, phi, and 28 hydrogen bonds) as input. Observation of some interactions between the sheet and previously identified alpha-helical regions made it possible to give an outline of the three-dimensional structure of the enzyme.
authors.affiliation: Inorganic Chemistry Laboratory, University of Oxford, U.K.
authors.forename: V
authors.initials: V
authors.lastname: Saudek
authors.forename: M R
authors.initials: MR
authors.lastname: Wormald
authors.forename: R J
authors.initials: RJ
authors.lastname: Williams
authors.forename: J
authors.initials: J
authors.lastname: Boyd
authors.forename: M
authors.initials: M
authors.lastname: Stefani
authors.forename: G
authors.initials: G
authors.lastname: Ramponi
mesh_terms: D017766:Acid Anhydride Hydrolases; D000595:Amino Acid Sequence; D000596:Amino Acids; D000818:Animals; D006736:Horses; D009682:Magnetic Resonance Spectroscopy; D008958:Models, Molecular; D008961:Models, Structural; D008969:Molecular Sequence Data; D009132:Muscles / Q000201:enzymology*; D010744:Phosphoric Monoester Hydrolases; D011487:Protein Conformation; D000097024:Acylphosphatase
chemical_list: D017766:Acid Anhydride Hydrolases; D000596:Amino Acids; D010744:Phosphoric Monoester Hydrolases; D000097024:Acylphosphatase