Aminoacyl-tRNA synthetases as drug targets in eukaryotic parasites

Abstract

Aminoacyl-tRNA synthetases are central enzymes in protein translation, providing the charged tRNAs needed for appropriate construction of peptide chains. These enzymes have long been pursued as drug targets in bacteria and fungi, but the past decade has seen considerable research on aminoacyl-tRNA synthetases in eukaryotic parasites. Existing inhibitors of bacterial tRNA synthetases have been adapted for parasite use, novel inhibitors have been developed against parasite enzymes, and tRNA synthetases have been identified as the targets for compounds in use or development as antiparasitic drugs. Crystal structures have now been solved for many parasite tRNA synthetases, and opportunities for selective inhibition are becoming apparent. For different biological reasons, tRNA synthetases appear to be promising drug targets against parasites as diverse as Plasmodium (causative agent of malaria), Brugia (causative agent of lymphatic filariasis), and Trypanosoma (causative agents of Chagas disease and human African trypanosomiasis). Here we review recent developments in drug discovery and target characterisation for parasite aminoacyl-tRNA synthetases.

Keywords: Aminoacyl-tRNA synthetase; Drug target; Parasite; Protein translation.

Graphical abstract

Fig. 1

Schematic representation of an aminoacyl-tRNA synthetase. Various aaRS domains are illustrated: the editing domain (red); catalytic domain (cyan); anticodon-binding domain (indigo); and parasite-specific domains (purple). Possible sites of interaction between aaRS and compound (with existing examples) are indicated by numbers: editing site (1); active site (2); allosteric sites (3); parasite-specific domains (4); and anticodon-binding site (5). (For interpretation of the references to colour in this figure legend, the reader is referred to the web version of this article.)