Exploring the mode of action of a novel antileishmanial compound using thermal proteome profiling and other OMICs tools

Compound 4, an antileishmanial compound identified in a GSK phenotypic-screen against Leishmania donovani (Leish-box)1 and not currently being actively researched for drug discovery, was investigated with the aim of elucidated its mode-of-action (MoA) in L. major and L. mexicana (two causative agents of cutaneous leishmaniasis). A novel pipeline approach was developed and utilised for this purpose; it included (1) characterising the mode-of-resistance of in vitro evolution-derived mutants via Illumina sequencing and cross-resistance studies against clinical antileishmanials and (2) investigating compound protein targets via thermal proteome profiling (TPP). TPP indicated differences between the two species in terms of the number and type of proteins being targeted by compound 4.