BIOCHEMISTRY OF SURFACE ANTIGENS OF TRYPANOSOMA CRUZI

A number of cell-surface antigens have been identified and isolated from Trypanosoma cruzi, all of which are glycoconjugates. These include a 90000 mol.wt. glycoprotein capable of inducing protective immunity in mice which is found on all stages of the parasite life cycle; a 72000 mol.wt glycoprotein found on insect stages of the life cycle which has been implicated in the control of differentiation; and a complex glycolipid (lipopeptidophospho-glycan) containing lipid, carbohydrate, phosphate and amino acids whose function is unknown. The structure and possible function of these and other glycoproteins from T. cruzi which have been less extensively studied is reviewed and possibly unusual biosynthetic pathways for glycosylation highlighted. Surface membranes of cells exhibit a number of housekeeping properties such as ion balance maintenance and nutrient transport. In addition to these properties, the surface membranes of