Leishmania infantum: tuning digitonin fractionation for comparative proteomic of the mitochondrial protein content.

Leishmania infantum belongs to the Kinetoplastidae that is characterized by a specific mitochondrial DNA, the kinetoplast. This parasite is responsible for both benign cutaneous leishmaniasis and severe visceral leishmaniasis in humans. Molecular determinants of such differences in pathogenesis are not well understood, and the parasites as well as their hosts may contribute to the disease phenotype. Factors that help parasite to adapt its metabolism to nutritional conditions encountered in different location might play pivotal roles in controlling parasite development in these various host environments. Thus, we have decided to initiate studies aimed to compare the mitochondrial protein content of L. infantum. To avoid the drawback caused by the most abundant proteins such as tubulin and proteins of the cytoskeleton present in whole cell extract, we have decided to fractionate the subcellular components of the cells. Using both cytosolic and mitochondrial markers, we have improved a protein pre-fractionation protocol using digitonin that allowed us to generate an enriched mitochondrial fraction.