Fig. 1

Primary sequence alignment (PSA) of LiMTAP, TbMTAP, huMTAP and huPNP obtained using T-coffee program. The PSA indicates regions of sequence divergence relating to the huPNP or to some regions in the N and C termini of the parasite proteins and in their central part. Pink- shaded residues indicate active site residues of the huMTAP and their corresponding residues on LiMTAP, TbMTAP and huPNP, on the alignment. These residues were described in human MTAP crystals as base-binding sites (cercles), methylthioribose-binding sites (stars) or sulfate/phosphate-binding sites (triangles). The parasite proteins and huMTAP share 11 out of 15 residues. The secondary structures (β-strands in green arrows and α-helices in red lines) are shown above the parasite proteins and huMTAP sequences. They align well to each other confirming correct PSA alignment