Phospholipid and glycolipid composition of acidocalcisomes of Trypanosoma cruzi.
Highly purified acidocalcisomes from Trypanosoma cruzi epimastigotes were obtained by differential centrifugation and iodixanol gradient ultracentrifugation. Lipid analysis of acidocalcisomes revealed the presence of low amounts of 3beta-hydroxysterols and predominance of phospholipids. Alkylacyl phosphatidylinositol (16:0/18:2), diacyl phosphatidylinositol (18:0/18:2), diacyl phosphatidylcholine (16:0/18:2; 16:1/18:2; 16:2/18:2; 18:1/18:2 and 18:2/18:2), and diacyl phosphatidylethanolamine (16:0/18:2 and 16:1/18:2) were the only phospholipids characterized by electrospray ionization-mass spectrometry (ESI-MS). Incubation of epimastigotes with [(3)H]-mannose and isolation of acidocalcisomes allowed the detection of a glycoinositolphospholipid (GIPL) in these organelles. The sugar content of the acidocalcisomal GIPL was similar to that of the GIPL present in a microsomal fraction but the amount of galactofuranose and inositol with respect to the other monosaccharides was lower, suggesting a different chemical structure. Taken together, these results indicate that acidocalcisomes of T. cruzi have a distinct lipid and carbohydrate composition.
Salto
María Laura
ML
Department of Pathobiology, University of Illinois at Urbana-Champaign, Urbana, IL 61802, United States.
Kuhlenschmidt
Theresa
T
Kuhlenschmidt
Mark
M
de Lederkremer
Rosa M
RM
Docampo
Roberto
R
D000818:Animals; D002118:Calcium / Q000378:metabolism; D002499:Centrifugation, Density Gradient; D006017:Glycolipids / Q000032:analysis*; D006863:Hydrogen-Ion Concentration; D015388:Organelles / Q000737:chemistry* / Q000648:ultrastructure; D010743:Phospholipids / Q000032:analysis*; D021241:Spectrometry, Mass, Electrospray Ionization; D014349:Trypanosoma cruzi / Q000254:growth & development / Q000648:ultrastructure*
D006017:Glycolipids; D010743:Phospholipids; D002118:Calcium