Structural features of the lipopeptidophosphoglycan from Trypanosoma cruzi common with the glycophosphatidylinositol anchors.
The lipopeptidophosphoglycan (LPPG) from Trypanosoma cruzi, a major constituent of the plasma membrane of epimastigote forms, has been now extracted with butanol/water from delipidated cells and purified by hydrophobic chromatography. We have found that the LPPG undergoes two reactions, characteristic of the glycosylphosphatidylinositol anchors: (a) cleavage of the ceramide by phosphatidylinositol-specific phospholipase C (PtdIns-specific phospholipase C) from Bacillus thuringiensis, (b) nitrous acid deamination of the non-N-acylated glucosamine. Palmitoylsphinganine, palmitoylsphingosine, lignoceroylsphinganine and, as minor components, the stearoylceramides were identified by gas liquid chromatography/mass spectrometry. The presence of cross reacting determinant (CRD) epitopes in the glycophosphoinositol released by PtdIns-specific phospholipase C was investigated by direct and inhibition ELISA. A sample of glycophosphoinositol containing 5 micrograms carbohydrate caused 60% inhibition of the binding of anti-CRD antibodies raised against the soluble form of variant surface glycoprotein.
de Lederkremer
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RM
Departamento de Química Orgánica, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Argentina.
Lima
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C
Ramirez
M I
MI
Casal
O L
OL
D000818:Animals; D002518:Ceramides / Q000302:isolation & purification; D002851:Chromatography, High Pressure Liquid; D004797:Enzyme-Linked Immunosorbent Assay; D006017:Glycolipids / Q000032:analysis*; D017261:Glycosylphosphatidylinositols; D010084:Oxidation-Reduction; D010457:Peptidoglycan / Q000032:analysis / Q000302:isolation & purification*; D010716:Phosphatidylinositols / Q000032:analysis*; D010743:Phospholipids / Q000032:analysis / Q000302:isolation & purification*; D014349:Trypanosoma cruzi / Q000032:analysis*; D010738:Type C Phospholipases
D002518:Ceramides; D006017:Glycolipids; D017261:Glycosylphosphatidylinositols; D010457:Peptidoglycan; D010716:Phosphatidylinositols; D010743:Phospholipids; C014643:lipopeptidophosphoglycan; D010738:Type C Phospholipases