Quantitative proteomic analysis reveals differential modulation of crucial stage specific proteins during promastigote to amastigote differentiation in Leishmania donovani

Leishmaniasis is a neglected tropical disease (NTD) caused by the protozoan parasite Leishmania . The disease has several clinical manifestations with visceral leishmaniasis (VL) being the most fatal. The apicomplexan protozoan has a digenetic life cycle between the sandfly vectors (promastigote stage) and the mammalian hosts (amastigote stage). Promastigote to amastigote differentiation is crucial for intracellular survival and for successful establishment of infection. However, the underlying molecular mechanisms still remain elusive. We investigated the proteome changes during the early differentiation stages of Leishmania donovani clinical isolate from an Amphotericin B (AmB) relapse patient. Sequential Window Acquisition of All Theoretical Mass Spectra (SWATH-MS) based quantitative proteomics revealed 814 and 921 differentially modulated proteins after 24 h and 48 h of promastigote to amastigote differentiation. We identified several key proteins like Tb-292-membrane-associated-protein-like-protein, Glycoprotein 96–92, p22 proteins, Maoc family dehydratase-like protein, KH domain-containing putative protein, Apolipoprotein-A1/A4/E-domain-containing-protein, Mkiaa0324 protein-like protein and Protein YIPF not reported hitherto. Several key metabolic proteins, proteases and proteins involved in post-translational modifications (PTM) were also differentially modulated between the amastigote and promastigote stages. Bioinformatics analyses of the proteomics data revealed several metabolic pathways viz., glycolysis, oxidative stress, fatty acid metabolism, asparagine/glutamine biosynthesis and purine/pyrimidine biosynthesis to be differentially regulated between the digenetic stages. Further studies to investigate the role of these proteins would allow better understanding of Leishmania pathogenesis and identification of targets for therapeutic intervention and biomarker studies. Data are available via ProteomeXchange with identifier PXD028775. Graphic abstract