An alpha D-globin fragment from Triatoma infestans hindgut stimulates Trypanosoma cruzi adenylyl cyclase and promotes metacyclogenesis.

FRAIDENRAICH D; PEÑA C; ISOLA EL; LAMMEL EM; COSO O; AÑEL AD; BARALLE F; TORRES HN; FLAWIA MM

BIOLOGICAL RESEARCH

SOC BIOLGIA CHILE

Año: 1993 p. 279 - 283

0716-9760

A peptide from hindguts of the Triatoma infestans, the hematophagous Chagas´ insect vector, activates adenylyl cyclase activity in Trypanosoma cruzi epimastigote membranes and stimulates the in vitro differentiation of epimastigotes (proliferative and non-infectious forms) to metacyclic trypomastigotes (non-proliferative and infectious forms). The peptide was purified from hindguts of insects fed two days before with chicken blood. After purification, the peptide showed upon SDS-PAGE a single band of about 10 kDa. The sequence for 20 residues of the amino terminus of this peptide was: H2N-Met-Leu-Thr-Ala-Glu-Asp-Lys-Lys-Leu-Ile-Gln-Gln-Ala-Trp-Glu-Lys-Ala- Ala-Ser-His. This sequence corresponds to the amino terminus of chicken alpha D-globin. A synthetic peptide with the sequence of the 40 amino acids corresponding to the amino terminus of alpha D-globin, also stimulated T. cruzi adenylyl cyclase activity and promoted metacyclogenesis.