title: L-Arabinose-binding protein-sugar complex at 2.4 A resolution. Stereochemistry and evidence for a structural change.
abstract: The L-arabinose molecule (in the C1 pyranose chair conformation) has been fitted to the electron density corresponding to the bound sugar in the 2.4 A resolution Fourier map of the L-arabinose-binding protein. The sugar molecule is buried in the cleft between the two lobes of the bilobate protein. All sugar hydroxyls are hydrogen-bonded to side chain residues: beta-OH(1) to Lys-10 and Asp-90, OH(2) to Lys-10, OH(3) to Asn-205 and Glu-14 (possibly via a water molecule), and OH(4) to Asn-232. Lys-10, Glu-14, and Asp-90 are associated with one domain while Asn-205 and Asn-232 are lodged in the other. Protein structural change accompanying binding is indicated by the inaccessibility of the bound L-arabinose to the aqueous environment.
mesh_terms: D001089:Arabinose / Q000378:metabolism*; D001426:Bacterial Proteins / Q000378:metabolism; D002352:Carrier Proteins / Q000378:metabolism*; D004926:Escherichia coli / Q000378:metabolism*; D029968:Escherichia coli Proteins; D008958:Models, Molecular; D011485:Protein Binding; D011487:Protein Conformation; D013237:Stereoisomerism; D014961:X-Ray Diffraction
chemical_list: C016242:AraF protein, E coli; D001426:Bacterial Proteins; D002352:Carrier Proteins; D029968:Escherichia coli Proteins; D001089:Arabinose