title: Structural and conformational analysis of glycan moieties in situ on isotopically 13C, 15N-enriched recombinant human chorionic gonadotropin.
abstract: The conformational properties in solution of the glycans on the alpha subunit of recombinant human chorionic gonadotropin are described, using high-resolution multinuclear NMR studies on uniformly 13C, 15N-enriched recombinant glycoprotein expressed in CHO cells. The glycan important for full biological activity of hCG, namely, that at Asn 52, appears to extend into solution both in the isolated alpha subunit and in complex with the beta subunit. The disposition of this glycan with respect to the protein backbone suggests that glycosylation maintains full biological activity of hCG either by interacting with a lectin-like region of the hCG receptor or by reducing the affinity of the hormone for the hCG receptor and preventing its down-regulation.
authors.affiliation: Centre for Biomolecular Sciences, University of St. Andrews, FIFE, U.K.
authors.forename: C T
authors.initials: CT
authors.lastname: Weller
authors.forename: J
authors.initials: J
authors.lastname: Lustbader
authors.forename: K
authors.initials: K
authors.lastname: Seshadri
authors.forename: J M
authors.initials: JM
authors.lastname: Brown
authors.forename: C A
authors.initials: CA
authors.lastname: Chadwick
authors.forename: C E
authors.initials: CE
authors.lastname: Kolthoff
authors.forename: S
authors.initials: S
authors.lastname: Ramnarain
authors.forename: S
authors.initials: S
authors.lastname: Pollak
authors.forename: R
authors.initials: R
authors.lastname: Canfield
authors.forename: S W
authors.initials: SW
authors.lastname: Homans
mesh_terms: D002236:Carbohydrate Conformation; D002240:Carbohydrate Sequence; D002247:Carbon Isotopes; D006063:Chorionic Gonadotropin / Q000737:chemistry*; D003198:Computer Simulation; D006023:Glycoproteins / Q000737:chemistry*; D006801:Humans; D009682:Magnetic Resonance Spectroscopy; D008958:Models, Molecular; D008969:Molecular Sequence Data; D009587:Nitrogen Isotopes; D011134:Polysaccharides / Q000737:chemistry*; D011994:Recombinant Proteins / Q000737:chemistry; D017421:Sequence Analysis
chemical_list: D002247:Carbon Isotopes; D006063:Chorionic Gonadotropin; D006023:Glycoproteins; D009587:Nitrogen Isotopes; D011134:Polysaccharides; D011994:Recombinant Proteins