Ultrastructural localization of glycoconjugates in Tritrichomonas foetus

Abstract.

We have probed Tritrichomonas foetus, a protozoan parasite of the urogenital tract of cattle, with gold-labeled and fluorescent lectins, for the localization of glycoconjugates, at the cell surface and in internal cell compartments. The following lectins were used: Con A, PNA, WGA, BSI, BSII, HPA, WFA, SBA, LFA, HPA, and LCA. Carbohydrates were also localized using the Thiéry's technique. Carbohydrate residues were observed in the Golgi and vesicles with all lectins used. However, the labeling pattern varied among the cisternae. A high heterogeneity of cell labeling was detected in the same preparation. The nucleus and the nuclear envelope were labeled with Con A, WGA, BSI, and UEA I, suggesting the presence of D-Man, and/or D-glucose, L-fucose, and GlcNAc. Lysosomes were labeled with Con A and intensely labeled with HPA. The intensity of labeling of the plasma and flagellar membranes varied according to the lectin used.