Characterization and expression of proteases during Trypanosoma cruzi metacyclogenesis.
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.
Bonaldo
M C
MC
Fundação Oswaldo Cruz, Departamento de Bioquimica e Biologia Molecular, Rio de Janeiro, Brasil.
d'Escoffier
L N
LN
Salles
J M
JM
Goldenberg
S
S
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
D011480:Protease Inhibitors; D003546:Cysteine Endopeptidases; D008666:Metalloendopeptidases