Learn More
The specificity of purified, peanut agglutinin has been studied immunochemically by quantitative precipitin and inhibition assays. The lectin showed substantial differences in precipitating with blood-group substances of the same specificity. Of the B substances tested, horse 4 25% completely precipitated the lectin, Beach phenol insoluble failed to(More)
The mechanisms by which the human enteric pathogen Giardia lamblia colonizes the proximal small intestine are poorly understood. Although the parasite possesses an attachment organelle on its ventral surface, the "sucking" disk, we considered that like many bacteria and some protozoa, G. lamblia might also have a surface membrane-associated modality for(More)
Trypanosoma cruzi at various stages of maturation and differentiation have been isolated by conventional cellular fractionation procedures and characterized by cell surface markers using 30 highly purified lectins encompassing all known sugar specificities. Cell surface carbohydrates of the various T. cruzi stages were analyzed by agglutination and(More)
Trypanosoma cruzi, the etiological agent of Chagas' disease, expresses a trans-sialidase at highest levels in infective trypomastigotes, where it attaches to the plasma membrane by a glycophosphoinositol linkage. Bound enzyme sheds into the extracellular milieu in a soluble form. Experiments performed in vitro suggest that the trans-sialidase participates(More)
The substrate specificity, physico-chemical, and kinetic properties of the trans-sialidase from Trypanosoma cruzi have been investigated. The enzyme demonstrates activity towards a wide range of saccharide, glycolipid, and glycoprotein acceptors which terminate with a beta-linked galactose residue, and synthesizes exclusively an alpha 2-3 sialosidic(More)
Trypanosoma cruzi expresses a developmentally regulated neuraminidase (TCNA) implicated in parasite invasion of cells. We isolated full-length DNA clones encoding TCNA. Sequence analysis demonstrated an open reading frame coding for a polypeptide of 1,162 amino acids. In the N-terminus there is a cysteine-rich domain containing a stretch of 332 amino acids(More)
The initial attachment of Cryptosporidium parvum sporozoites to host cells in vivo may be a critical event in the pathogenesis of this infection. The molecular basis of attachment and the conditions influencing this host-parasite interaction have not been studied systematically. Therefore, we have developed a sporozoite attachment model by using(More)
T. cruzi invades mammalian cells in various organs after migrating through the ECM. These activities appear to be mediated by a unique 60 kd protein exposed on the T. cruzi surface, which promotes selective adhesion of trypomastigotes to three ECM components: heparin, heparan sulfate, and collagen. The affinity-purified protein binds to host fibroblasts in(More)