title: [Description of an acidic peptidase, insensitive to classical inhibitors, in protein extracts of Trypanosoma cruzi, from a rural area of Venezuela, where Chagas disease is endemic].
abstract: Through two peptidase assay methods, one in liquid-phase and another, in gel-phase (gel zymography), an acid peptidase was detected in protein crude extracts of epimastigotes of Trypanosoma cruzi, from a rural area of Venezuela where Chagas disease is endemic. The peptidase shows activity at a pH range between 2.0 and 2.9. Under the experimental conditions described, the acid peptidase was insensitive to usual concentrations of peptidase inhibitors of the types: serine, cysteine, aspartic and metallopeptidases. Nevertheless, like porcine pepsin at pH 2.9, the peptidase was inhibited in the presence of 5mM DTT.
authors.affiliation: Laboratorio de Bioquímica de Parásitos, Servicio Autónomo Instituto de Biomedicina, Caracas, Venezuela. zambranoedgar@hotmail.com
authors.forename: Edgar Armando
authors.initials: EA
authors.lastname: Zambrano
authors.affiliation: Laboratorio de Bioquímica de Parásitos, Servicio Autónomo Instituto de Biomedicina, Caracas, Venezuela.
authors.forename: Henry Samuel
authors.initials: HS
authors.lastname: de la Cruz
authors.affiliation: Laboratorio de Bioquímica de Parásitos, Servicio Autónomo Instituto de Biomedicina, Caracas, Venezuela.
authors.forename: Blanca Elena
authors.initials: BE
authors.lastname: Coita
mesh_terms: D014355:Chagas Disease / Q000469:parasitology; D019353:Endemic Diseases; D006454:Hemoglobins / Q000378:metabolism; D006801:Humans; D006863:Hydrogen-Ion Concentration; D006868:Hydrolysis; D010436:Pepstatins / Q000494:pharmacology; D010447:Peptide Hydrolases / Q000302:isolation & purification* / Q000378:metabolism; D011480:Protease Inhibitors / Q000494:pharmacology; D015800:Protozoan Proteins / Q000037:antagonists & inhibitors / Q000302:isolation & purification* / Q000378:metabolism; D013379:Substrate Specificity; D014349:Trypanosoma cruzi / Q000201:enzymology* / Q000254:growth & development / Q000302:isolation & purification; D014687:Venezuela
chemical_list: D006454:Hemoglobins; D010436:Pepstatins; D011480:Protease Inhibitors; D015800:Protozoan Proteins; D010447:Peptide Hydrolases