The occurrence of N-acetyl- and N-glycoloylneuraminic acid in Trypanosoma cruzi.

Different strain of Trypanosoma cruzi were analysed to have 65--105 micrograms of sialic acids per 10(10) cells. By thin-layer chromatography, and in part by gas liquid chromatography and gas-liquid chromatography-mass spectrometry, all strains were found to contain N-acetyl- and N-glycoloylneuraminic acid in various ratios. After incubation of the parasites with either [3H]acetate or N-acetyl-[3H]mannosamine, no radioactivity was found in the sialic acids, thus leading to the suggestion that the parasites are unable to synthesize sialic acids from their precursors.