title: Anomer-Specific Recognition and Dynamics in a Fucose-Binding Lectin.
abstract: Sugar binding by a cell surface ∼29 kDa lectin (RSL) from the bacterium Ralstonia solanacearum was characterized by NMR spectroscopy. The complexes formed with four monosaccharides and four fucosides were studied. Complete resonance assignments and backbone dynamics were determined for RSL in the sugar-free form and when bound to l-fucose or d-mannose. RSL was found to interact with both the α- and the β-anomer of l-fucose and the "fucose like" sugars d-arabinose and l-galactose. Peak splitting was observed for some resonances of the binding site residues. The assignment of the split signals to the α- or β-anomer was confirmed by comparison with the spectra of RSL bound to methyl-α-l-fucoside or methyl-β-l-fucoside. The backbone dynamics of RSL were sensitive to the presence of ligand, with the protein adopting a more compact structure upon binding to l-fucose. Taking advantage of tryptophan residues in the binding sites, we show that the indole resonance is an excellent reporter on ligand binding. Each sugar resulted in a distinct signature of chemical shift perturbations, suggesting that tryptophan signals are a sufficient probe of sugar binding.
authors: School of Chemistry, National University of Ireland Galway , University Road, Galway, Ireland.|Department of Food BioSciences, Teagasc Food Research Centre , Ashtown, Dublin 15, Ireland.
authors: Paweł M
authors: PM
authors: Antonik
authors: Jean Jeener NMR Centre, Structural Biology Brussels, Vrije Universiteit Brussel , Pleinlaan 2, 1050 Brussels, Belgium.|Structural Biology Research Centre, VIB, Pleinlaan 2, 1050 Brussels, Belgium.
authors: Alexander N
authors: AN
authors: Volkov
authors: School of Chemistry, National University of Ireland Galway , University Road, Galway, Ireland.
authors: Ursula N
authors: UN
authors: Broder
authors: School of Chemistry, National University of Ireland Galway , University Road, Galway, Ireland.
authors: Daniele Lo
authors: DL
authors: Re
authors: Jean Jeener NMR Centre, Structural Biology Brussels, Vrije Universiteit Brussel , Pleinlaan 2, 1050 Brussels, Belgium.|Structural Biology Research Centre, VIB, Pleinlaan 2, 1050 Brussels, Belgium.
authors: Nico A J
authors: NA
authors: van Nuland
authors: School of Chemistry, National University of Ireland Galway , University Road, Galway, Ireland.
authors: Peter B
authors: PB
authors: Crowley
mesh_terms: D000595:Amino Acid Sequence; D001426:Bacterial Proteins / Q000737:chemistry / Q000378:metabolism*; D005643:Fucose / Q000031:analogs & derivatives / Q000378:metabolism*; D037102:Lectins / Q000737:chemistry / Q000378:metabolism*; D008358:Mannose / Q000378:metabolism; D008958:Models, Molecular; D008969:Molecular Sequence Data; D011485:Protein Binding; D043368:Ralstonia solanacearum / Q000737:chemistry / Q000378:metabolism*; D016415:Sequence Alignment
chemical_list: D001426:Bacterial Proteins; D037102:Lectins; C027112:fucose-binding lectin; D005643:Fucose; D008358:Mannose