Identification of and Structural Insights into Hit Compounds Targeting -Myristoyltransferase for Drug Development.

Each year, approximately 50,000 children under 5 die as a result of diarrhea caused by , a protozoan parasite. There are currently no effective drugs or vaccines available to cure or prevent infection, and there are limited tools for identifying and validating targets for drug or vaccine development. We previously reported a high throughput screening (HTS) of a large compound library against -myristoyltransferase (NMT), a validated drug target in multiple protozoan parasite species. To identify molecules that could be effective against , we counter-screened hits from the NMT HTS against NMT. We identified two potential hit compounds and validated them against NMT to determine if NMT might be an attractive drug target also for . We tested the compounds against using both cell-based and NMT enzymatic assays. We then determined the crystal structure of NMT bound to Myristoyl-Coenzyme A (MyrCoA) and structures of ternary complexes with MyrCoA and the hit compounds to identify the ligand binding modes. The binding site architectures display different conformational states in the presence of the two inhibitors and provide a basis for rational design of selective inhibitors.