title: Crystallization and preliminary X-ray analysis of an intact soluble-form variant surface glycoprotein from the African trypanosome, Trypanosoma brucei.
abstract: The intact variant surface glycoprotein (VSG) ILTat 1.24 from Trypanosoma brucei has been crystallized. An amino-terminal domain of the protein comprising two thirds of the sequence had been crystallized previously after proteolytic digestion. Now intact VSG crystals have been grown from 50 mM-Mes (pH 6.5) containing 62% (w/v) saturated ammonium sulfate. The crystals are demonstrated to contain the intact VSG by h.p.l.c. gel filtration and reaction with an antibody to the inositol phosphate oligosaccharide on the VSG carboxy terminus. The space group of the crystals is P6(2)22 (or P6(4)22) with unit cell dimensions a = b = 184 A and c = 214 A. Preparative isoelectric focusing may have facilitated crystallization.
authors.affiliation: Department of Biochemistry and Molecular Biology, Harvard University, Cambridge, MA 02138.
authors.forename: J A
authors.initials: JA
authors.lastname: Down
authors.forename: S C
authors.initials: SC
authors.lastname: Garman
authors.forename: A M
authors.initials: AM
authors.lastname: Gurnett
authors.forename: M J
authors.initials: MJ
authors.lastname: Turner
authors.forename: D C
authors.initials: DC
authors.lastname: Wiley
mesh_terms: D000645:Ammonium Sulfate; D000818:Animals; D000906:Antibodies / Q000276:immunology; D002851:Chromatography, High Pressure Liquid; D006801:Humans; D007295:Inositol Phosphates / Q000276:immunology; D009844:Oligosaccharides / Q000276:immunology; D012995:Solubility; D014346:Trypanosoma brucei brucei / Q000032:analysis*; D014643:Variant Surface Glycoproteins, Trypanosoma / Q000737:chemistry* / Q000276:immunology; D014961:X-Ray Diffraction
chemical_list: D000906:Antibodies; D007295:Inositol Phosphates; D009844:Oligosaccharides; D014643:Variant Surface Glycoproteins, Trypanosoma; D000645:Ammonium Sulfate