A recombinant form of chagasin from Trypanosoma cruzi: inhibitory activity on insect cysteine proteinases.

Background: The activity of the major digestive cysteine proteinase detected in the intestinal tract of larvae of the bean weevil, Acanthoscelides obtectus (Say), was efficiently inhibited by the well-characterized cysteine proteinase synthetic inhibitor E-64 and also by a recombinant form of chagasin (r-chagasin), a tight-binding cysteine proteinase inhibitor protein from Trypanosoma cruzi.

Results: Incorporation of r-chagasin into an artificial diet system at 0.1 g kg(-1) retarded growth rate, decreased larval survival and led to complete mortality of A.