title: Characterization and expression of proteases during Trypanosoma cruzi metacyclogenesis.
abstract: Investigation of protease activities during the transformation of Trypanosoma cruzi epimastigotes into metacyclic trypomastigoes (metacyclo-genesis) revealed three major components with apparent molecular weights of 65, 52, and 40 kDa. The 65-kDa protease is a metacyclic trypomastigote stage-specific protease with an isoelectric point of 5.2 whose activity is inhibited by 1,10-phenanthroline, suggesting that it might be a metalloprotease. The 52-kDa component is also a metalloprotease which is constitutively expressed in epimastigotes and metacyclic trypomastigoes. On the other hand, the 40-kDa component is apparently made up of several isoforms of a cysteine protease which is expressed in much higher levels in epimastigotes than in metacyclic trypomastigote forms. The fact that the 65- and 40-kDa proteases are developmentally regulated suggests that proteases might be important for T. cruzi differentiation. Accordingly, T. cruzi metacyclogenesis is blocked by metallo- and cysteine-protease inhibitors.
authors.affiliation: Fundação Oswaldo Cruz, Departamento de Bioquimica e Biologia Molecular, Rio de Janeiro, Brasil.
authors.forename: M C
authors.initials: MC
authors.lastname: Bonaldo
authors.forename: L N
authors.initials: LN
authors.lastname: d'Escoffier
authors.forename: J M
authors.initials: JM
authors.lastname: Salles
authors.forename: S
authors.initials: S
authors.lastname: Goldenberg
mesh_terms: D000818:Animals; D003546:Cysteine Endopeptidases / Q000737:chemistry / Q000378:metabolism*; D004591:Electrophoresis, Polyacrylamide Gel; D006863:Hydrogen-Ion Concentration; D007526:Isoelectric Point; D008666:Metalloendopeptidases / Q000737:chemistry / Q000378:metabolism*; D008970:Molecular Weight; D011480:Protease Inhibitors / Q000494:pharmacology; D014349:Trypanosoma cruzi / Q000187:drug effects / Q000201:enzymology* / Q000254:growth & development
chemical_list: D011480:Protease Inhibitors; D003546:Cysteine Endopeptidases; D008666:Metalloendopeptidases