title: Characterization of ecto-phosphatase activities of Trypanosoma cruzi: a comparative study between Colombiana and Y strains.
abstract: The etiological agent of Chagas disease, Trypanosoma cruzi, is consisted of two phylogenetic lineages. Using live epimastigotes, in this study we have characterized ecto-phosphatase activities of two strains of T. cruzi, one (Y strain) is a member of group T. cruzi I and the other (Colombiana) is a member of group T. cruzi II. About one-third of the total ecto-phosphatase activity from the Y strain was Mg(2+)-dependent, but no such activity was observed with Colombiana. The level of Mg(2+)-independent activity was dramatically different in the two strains, with Colombiana showing more than 15-fold higher activity. Experiments using classical inhibitors of acid phosphatases, as well as inhibitors of phosphotyrosine phosphatase, showed a decrease in these phosphatase activities, with different patterns of inhibition. The Mg(2+)-independent activities of the Colombiana and Y strains decreased inversely with pH, varying from 6.5 to 8.0. On the other hand, the Mg(2+)-dependent activity of the Y strain increased concomitantly with the increase in pH in the same range.
authors.affiliation: Disciplina de Parasitologia, DPL, FCM, UERJ, Rua Prof. Manoel de Abreu 444, Vila Isabel, Rio de Janeiro, RJ 20550-170, Brazil.
authors.forename: P M L
authors.initials: PM
authors.lastname: Dutra
authors.forename: L C
authors.initials: LC
authors.lastname: Couto
authors.forename: A H C S
authors.initials: AH
authors.lastname: Lopes
authors.forename: J R
authors.initials: JR
authors.lastname: Meyer-Fernandes
mesh_terms: D000135:Acid Phosphatase / Q000037:antagonists & inhibitors / Q000378:metabolism; D000818:Animals; D002413:Cations, Divalent / Q000494:pharmacology; D004791:Enzyme Inhibitors / Q000494:pharmacology; D006863:Hydrogen-Ion Concentration; D008274:Magnesium / Q000378:metabolism; D010744:Phosphoric Monoester Hydrolases / Q000037:antagonists & inhibitors / Q000378:metabolism*; D017027:Protein Tyrosine Phosphatases / Q000037:antagonists & inhibitors / Q000378:metabolism; D013045:Species Specificity; D014349:Trypanosoma cruzi / Q000145:classification* / Q000201:enzymology* / Q000254:growth & development
chemical_list: D002413:Cations, Divalent; D004791:Enzyme Inhibitors; D000135:Acid Phosphatase; D010744:Phosphoric Monoester Hydrolases; D017027:Protein Tyrosine Phosphatases; D008274:Magnesium