No abstract

Freeze-fracture techniques reveal differences in fine structure between the anterior three flagella of Tritrichomonas foetus and its recurrent flagellum. The anterior flagella have rosettes of 9-12 intramembranous particles on both the P and E faces. The recurrent flagellum lacks rosettes but has ribbon-like arrays of particles along the length of the flagellum, which may be involved in the flagellum's attachment to the cell body. This flagellum is attached to the membrane of the cell body along a distinct groove that contains few discernible particles. Some large intramembranous particles are visible on the P face of the cell body membrane at the point where the flagellum emerges from the cell body. The randomly distributed particles on the P and E faces of the plasma membrane have a particle density of 919/micron2 and 468/micron2 respectively, and there are areas on both faces that are devoid of particles. Freeze-fracture techniques also reveal numerous fenestrations in the membrane of the Golgi complex and about 24 pores per micron2 in the nuclear membrane.

The cell surface of Tritrichomonas foetus was characterized by using 18 highly purified lectins with specificities for N-acetyl glucosamine, N-acetyl galactosamine, galactose, mannose, and sialic acid. The specificity of the lectin-induced cell agglutination was verified by inhibition of the agglutination with the specific sugars. By using cytochemical techniques associated with electron microscopy, carbohydrates were detected on the cell surface of T. foetus. The following techniques were used: periodic acid--thiosemicarbazide--silver proteinate, concanavalin A--horseradish peroxidase, and ruthenium red. Anionic sites were detected on the cell surface of the protozoan at pH's 1.8 and 7.2 with the use of colloidal iron hydroxide and cationized ferritin particles, respectively. The binding of colloidal iron particles, as well as the agglutination induced by the lectin from Limulus polyphemus, indicated the presence of sialic acid on the cell surface of T. foetus.

No abstract

No abstract