Novel Antimicrobial Development by Targeting the First Two Committed Enzymes in the Methyl Erythritol Phosphate Pathway, DXP Reductoisomerase and MEP Cytidylyltransferase




Haymond, Amanda Nicole

Journal Title

Journal ISSN

Volume Title



The threat of both natural and engineered acquisition of antibiotic resistance by microbes necessitates development of novel antimicrobial compounds. The methyl erythritol phosphate (MEP) pathway presents a unique opportunity for such development, as it is both essential in bacteria in which it is found, as well as absent in mammalian cells. The MEP pathway produces two five-carbon lipid precursors isopentenyl pyrophosphate (IPP) and dimethylallyl pyrophosphate (DMAPP), essential cellular building blocks that condense to produce a host of vital downstream isoprenoids. The first two committed enzymes in the pathway, DXP reductoisomerase (IspC) and MEP cytidylyltransferase (IspD), are both promising targets for antimicrobial development. Herein we describe three approaches to identifying and developing novel inhibitors (rational, structure-based drug design; high-throughput screening of a commercial compound library; and high-throughput screening of a natural product library) conducted with both IspC and IspD in order to explore the chemical space for inhibition of these enzymes. To aid in screening a large commercially purchased compound library, we also describe the validation of a high-throughput screening protocol with respect to both IspC and IspD, with appropriate control assays to identify false positive compounds. Based on these library screens, we report promising lead compounds with respect to both enzymes, and propose models for their mechanism of action.



Biochemistry, Antibiotics, Antimicrobial development, Antimicrobial resistance, Enzymology, MEP pathway