Electrophoretic analysis of the polypeptides of Leishmania amastigotes and promastigotes

The polypeptides of Leishmania mexicana mexicana (M379), L. m. amazonensis (LV78), L. major (LV39) and L. d. donovani (LV39) amastigotes and cultured promastigotes have been analysed by SDS-polyacrylamide gel electrophoresis. The polypeptide banding patterns of the promastigotes of the four species were quite similar, but distinct differences were detected between those of amastigotes. The results suggest that the various species of Leishmania are adapted differently for survival and growth in the mammalian host. The polypeptides of L. m. mexicana amastigotes were very rapidly hydrolysed unless protected by the cysteine proteinase inhibitor leupeptin.