title: The glycoinositol-phospholipids of Phytomonas.
abstract: The Phytomonas spp. are trypanosomatid parasites of plants. A polar glycolipid fraction of a Phytomonas sp., isolated from the plant Euphorbia characias and grown in culture, was fractionated into four major glycolipid species (Phy 1-4). The glycolipids were analysed by chemical and enzymic modifications, composition and methylation analyses, electrospray mass spectrometry and microsequencing after HNO2 deamination and NaB3H4 reduction. The water-soluble headgroup of the Phy2 glycolipid was also analysed by 1H NMR. All four glycolipids were shown to be glycoinositol-phospholipids (GIPLs) with phosphatidylinositol (PI) moieties containing the fully saturated alkylacylglycerol lipids 1-O-hexadecyl-2-O-palmitoylglycerol and 1-O-hexadecyl-2-O-stearoylglycerol. The structures of the Phy 1-4 GIPLs are: Man alpha 1-2Man alpha 1-6Man alpha 1-4GlcN alpha 1-6PI, Glc alpha 1-2(NH2-CH2CH2-HPO4-)Man alpha 1-2Man alpha 1-6Man alpha 1-4GlcN alpha 1-6PI, [formula: see text] Glc alpha 1-2(NH2CH2CH2-HPO4-)Man alpha 1-2Man alpha 1-6Man alpha 1-4(NH2-CH2CH2-HPO4-)GlcN alpha 1-6PI [formula: see text] and Glc alpha 1-2Glc alpha 1-2(NH2CH2-CH2-HPO4-)Man alpha 1-2Man alpha 1-6Man alpha 1-4(NH2CH2CH2-HPO4-)-GlcN alpha 1-6PI. [formula: see text] The Phytomonas GIPLs represent a novel series of structures. This is the first description of the chemical structure of cell-surface molecules of this plant pathogen. The Phytomonas GIPLs are compared with those of other trypanosomatid parasites and are discussed with respect to trypanosomatid phylogenetic relationships.
mesh_terms: D000818:Animals; D002240:Carbohydrate Sequence; D002855:Chromatography, Thin Layer; D006017:Glycolipids / Q000032:analysis / Q000737:chemistry / Q000302:isolation & purification; D017261:Glycosylphosphatidylinositols / Q000032:analysis* / Q000737:chemistry / Q000302:isolation & purification; D013058:Mass Spectrometry; D008745:Methylation; D008969:Molecular Sequence Data; D010716:Phosphatidylinositols / Q000032:analysis; D010944:Plants / Q000469:parasitology; D011134:Polysaccharides / Q000032:analysis; D014351:Trypanosomatina / Q000737:chemistry* / Q000302:isolation & purification
chemical_list: D006017:Glycolipids; D017261:Glycosylphosphatidylinositols; D010716:Phosphatidylinositols; D011134:Polysaccharides