Structural studies on the polar glycoinositol phospholipids of Trypanosoma (Schizotrypanum) dionisii from bats.

ABSTRACT

The polar glycoinositol phospholipids (GIPLs) of a Trypanosoma species that belongs to the Schizotrypanum subgenus were purified by reversed-phase and normal-phase liquid chromatography and analysed by negative-ion mode electrospray-mass spectrometry (ES-MS). The phosphatidylinositol moieties were released by nitrous acid deamination and identified as ceramide- and alkylacylglycerol-containing species. The structures of the GIPLs were determined using chemical treatments, sequential exoglycosidase digestions and positive-ion mode ES-MS-MS. All of the GIPLs were based on the same Man alpha1-2Man alpha1-2Man alpha1-6Man alpha1-4(NH2-CH2CH2-HPO3-)GlcN-PI core with single terminal Galf residue substitutions either on the terminal nonreducing Man or on the second alphaMan residue from the inositol and with either ethanolamine phosphate or 2-aminoethylphosphonate on the third alphaMan residue from the inositol. The T. (S.) dionisii GIPLs are compared with those of T. (S.) cruzi, a closely related species of the Schizotrypanum subgenus.