title: Exploiting Uniformly13C-Labeled Carbohydrates for Probing Carbohydrate-Protein Interactions by NMR Spectroscopy.
abstract: NMR of a uniformly13C-labeled carbohydrate was used to elucidate the atomic details of a sugar-protein complex. The structure of the13C-labeled Manα(1-2)Manα(1-2)ManαOMe trisaccharide ligand, when bound to cyanovirin-N (CV-N), was characterized and revealed that in the complex the glycosidic linkage torsion angles between the two reducing-end mannoses are different from the free trisaccharide. Distances within the carbohydrate were employed for conformational analysis, and NOE-based distance mapping between sugar and protein revealed that Manα(1-2)Manα(1-2)ManαOMe is bound more intimately with its two reducing-end mannoses into the domain A binding site of CV-N than with the nonreducing end unit. Taking advantage of the13C spectral dispersion of13C-labeled carbohydrates in isotope-filtered experiments is a versatile means for a simultaneous mapping of the binding interactions on both, the carbohydrate and the protein.
authors.affiliation: Department of Structural Biology, University of Pittsburgh School of Medicine , Pittsburgh, Pennsylvania 15261, United States.
authors.forename: Gustav
authors.identifier: 0000-0001-8372-8811
authors.initials: G
authors.lastname: Nestor
authors.affiliation: Centre for Synthesis and Chemical Biology, University College Dublin , Belfield, Dublin 4, Ireland.
authors.forename: Taigh
authors.initials: T
authors.lastname: Anderson
authors.affiliation: Centre for Synthesis and Chemical Biology, University College Dublin , Belfield, Dublin 4, Ireland.
authors.forename: Stefan
authors.initials: S
authors.lastname: Oscarson
authors.affiliation: Department of Structural Biology, University of Pittsburgh School of Medicine , Pittsburgh, Pennsylvania 15261, United States.
authors.forename: Angela M
authors.identifier: 0000-0001-9072-3525
authors.initials: AM
authors.lastname: Gronenborn
mesh_terms: D001426:Bacterial Proteins / Q000737:chemistry* / Q000302:isolation & purification; D001665:Binding Sites; D002241:Carbohydrates / Q000138:chemical synthesis / Q000737:chemistry*; D002247:Carbon Isotopes; D002352:Carrier Proteins / Q000737:chemistry* / Q000302:isolation & purification; D019906:Nuclear Magnetic Resonance, Biomolecular
chemical_list: D001426:Bacterial Proteins; D002241:Carbohydrates; D002247:Carbon Isotopes; D002352:Carrier Proteins; C107733:cyanovirin N