Homologues of LMPK, a mitogen-activated protein kinase from Leishmania mexicana, in different Leishmania species.

LMPK, a mitogen-activated protein (MAP) kinase homologue of Leishmania mexicana, is essential for the proliferation of the amastigote, the mammalian stage of the protozoan parasite. This has been demonstrated using deletion mutant promastigotes, the insect stage of the parasite: first, in vitro after differentiation to amastigotes, which subsequently lost their potential to proliferate; second, by infection of peritoneal macrophages, which were able to cope with the infection and cleared the parasites; third, by infection of BALB/c mice, which showed no lesion development. The lmpk deletion mutant promastigotes are a potential live vaccine because they infect macrophages, transform to amastigotes and deliver amastigote antigens to raise an immune response without causing the disease. In addition, inhibition of LMPK in a wild-type infection is likely to resolve the disease and as such, is an ideal target for drug development against leishmaniasis. Here we investigated the presence and copy number of lmpk homologues in Leishmania amazonensis, L. major, L. tropica, L. aethiopica, L. donovani, L. infantum, and L. braziliensis and discuss the results with regard to drug development and vaccination using kinase deletion mutants.