title: Crystal structure of fucose-specific lectin from Aleuria aurantia binding ligands at three of its five sugar recognition sites.
abstract: Aleuria aurantia possesses a fucose-specific lectin (AAL) that is widely used as a specific probe for fucose. Fucosylated sugars often play pivotal roles in many cellular processes. We have determined the crystal structure of AAL at 2.24 A resolution in complex with only three fucose molecules in its five sugar binding sites of a six-fold beta-propeller structure. Very recently, the structure of AAL has been independently determined, showing that all the five binding sites were occupied by fucose molecules [Wimmerova, M., et al. (2003) J. Biol. Chem. 278, 27059-27067]. Stabilization of the arginine conformation bound to fucose molecules plays an essential role in generating the difference in the affinity in the five binding sites. Binding models with a couple of saccharides based on biochemical assays suggest that hydrophobic contacts also play important roles in AAL recognizing its ligand.
mesh_terms: D000595:Amino Acid Sequence; D001203:Ascomycota / Q000737:chemistry; D001665:Binding Sites; D018360:Crystallography, X-Ray; D005643:Fucose / Q000378:metabolism*; D005656:Fungal Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D037102:Lectins / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism*; D008024:Ligands; D008958:Models, Molecular; D008969:Molecular Sequence Data; D011485:Protein Binding; D017433:Protein Structure, Secondary; D011994:Recombinant Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D016415:Sequence Alignment; D017386:Sequence Homology, Amino Acid; D020080:Tandem Repeat Sequences
chemical_list: D005656:Fungal Proteins; D037102:Lectins; D008024:Ligands; D011994:Recombinant Proteins; C064549:lectin, Aleuria aurantia; D005643:Fucose