Fig. 1

LmABCB3 contains a unique N-terminal extension (UNE). a Schematic representation of LmABCB3 containing mRNA. In phase ATG codons found in 5‘ UTR and TGA Stop codon are indicated. b Schematic representation of LmABCB3 (up) showing the unique N-terminal extension (UNE), the Transmembrane Domain (TMD) and the Nucleotide Binding domain (NBD), indicating the K⁶⁷⁵M mutation (K/M) in the conserved Walker A motif that inactivates the protein. The schematic representation of the UNE region (down) highlights several motifs and sequences: i) a putative Mitochondrial Localization Signal (MLS) with conserved MLRR motif (underlined in red) and Arg (red) and hydrophobic Ala, Val and Leu residues (green); ii) a putative transmembrane segment (TM); iii) a TRASH domain with conserved Cys probably involved in metal co-ordination (red) and other residues (green) conserved in 70 % of TRASH domains [50]; iv) a Glycine/Serine repeat and iv) a putative signal peptide (red line). c Phylogenetic analysis of mitochondrial ABCB transporter sequences from Leishmania, mammals and yeast. Aligned protein sequences were subjected to phylogenetic analysis as described in Methods. The human representative of each mammalian subfamily was incorporated in the analysis to define each subfamily. Lm: L. major; Tb: T. brucei; Tc: T. cruzi; Hs: H. sapiens; Sc: S. cereviciae