title: Structural characterization of novel inositol phosphosphingolipids of Tritrichomonas foetus and Trichomonas vaginalis.
abstract: Two major ethanolamine phosphate-substituted inositol phosphosphingolipids have been identified in the unsaponifiable acidic lipid fractions of Tritrichomonas foetus and Trichomonas vaginalis. The compounds were radiolabelled and purified by high-performance thin-layer chromatography followed by high-performance liquid chromatography. The structures were determined by a combination of tandem mass spectrometry (MS/MS) and nuclear magnetic resonance (NMR) experiments, and gas-liquid chromatography of components obtained by degradation and derivatization. Inositol in the T. foetus component was 1-linked to the phosphosphingolipid, had the phosphoethanolamine group at the 3-position and a fucosyl residue at the 4-position. The T. vaginalis component lacked the fucosyl moiety. Both organisms also produced inositol phosphosphingolipids having the same long-chain base (sphingosine or dihydrosphingosine) and the same fatty acyl distribution as the inositol diphosphate compounds. These glycosphingolipids may represent metabolic intermediates for new types of membrane anchors for surface glycopeptides or glycolipids that mediate the host-parasite relationship of these trichomonads. The MS/MS and NMR spectroscopic data should provide reference information for structural determinations of other phosphorylated inositol derivatives.
authors.affiliation: Department of Chemistry, Massachusetts Institute of Technology, Cambridge 02139.
authors.forename: C E
authors.initials: CE
authors.lastname: Costello
authors.forename: J
authors.initials: J
authors.lastname: Glushka
authors.forename: H
authors.initials: H
authors.lastname: van Halbeek
authors.forename: B N
authors.initials: BN
authors.lastname: Singh
mesh_terms: D000818:Animals; D002236:Carbohydrate Conformation; D002240:Carbohydrate Sequence; D002518:Ceramides / Q000032:analysis; D002849:Chromatography, Gas / Q000379:methods; D002850:Chromatography, Gel / Q000379:methods; D002851:Chromatography, High Pressure Liquid / Q000379:methods; D002852:Chromatography, Ion Exchange / Q000379:methods; D002855:Chromatography, Thin Layer / Q000379:methods; D019856:Ethanolamine; D004983:Ethanolamines / Q000032:analysis; D005643:Fucose / Q000032:analysis; D007295:Inositol Phosphates / Q000737:chemistry* / Q000302:isolation & purification; D009682:Magnetic Resonance Spectroscopy / Q000379:methods; D013058:Mass Spectrometry / Q000379:methods; D008968:Molecular Conformation; D008969:Molecular Sequence Data; D013107:Sphingolipids / Q000737:chemistry* / Q000302:isolation & purification; D014246:Trichomonas vaginalis / Q000737:chemistry*; D016835:Tritrichomonas foetus / Q000737:chemistry*
chemical_list: D002518:Ceramides; D004983:Ethanolamines; D007295:Inositol Phosphates; D013107:Sphingolipids; D005643:Fucose; D019856:Ethanolamine; C005448:phosphorylethanolamine