Toolkit of Approaches To Support Target-Focused Drug Discovery for Plasmodium falciparum Lysyl tRNA Synthetase

Rachel Milne, Natalie Wiedemar, Victoriano Corpas-Lopez, Eoin Moynihan, Richard J. Wall, Alice Dawson, David A. Robinson, Sharon M. Shepherd, Robert J. Smith, Irene Hallyburton, John M. Post, Karen Dowers, Leah S. Torrie, Ian H. Gilbert, Beatriz Baragaña, Stephen Patterson, and Susan Wyllie.

ACS Infect. Dis. 2022, 8, 9, 1962–1974
Publication Date:August 29, 2022


There is a pressing need for new medicines to prevent and treat malaria. Most antimalarial drug discovery is reliant upon phenotypic screening. However, with the development of improved target validation strategies, target-focused approaches are now being utilized. Here, we describe the development of a toolkit to support the therapeutic exploitation of a promising target, lysyl tRNA synthetase (PfKRS). The toolkit includes resistant mutants to probe resistance mechanisms and on-target engagement for specific chemotypes; a hybrid KRS protein capable of producing crystals suitable for ligand soaking, thus providing high-resolution structural information to guide compound optimization; chemical probes to facilitate pulldown studies aimed at revealing the full range of specifically interacting proteins and thermal proteome profiling (TPP); as well as streamlined isothermal TPP methods to provide unbiased confirmation of on-target engagement within a biologically relevant milieu. This combination of tools and methodologies acts as a template for the development of future target-enabling packages.