Science Pool

Discovery of Novel UDP-N-Acetylglucosamine Acyltransferase (LpxA) Inhibitors

Alastair Parkes, Ph.D, Group Leader, Discovery Chemistry, Evotec UK

As part of our ongoing efforts at Evotec to tackle AMR through the design of novel antibiotics we have been working with Boston-based X-Biotix in a collaboration focussed on targeting priority Gram-negative pathogens. We are now able to share the story of our work on inhibitors of UDP-N-Acetylglucosamine Acyltransferase (LpxA), a key enzyme in the biosynthetic pathway of the outer membrane lipopolysaccharide of Gram-negative bacteria. Building on hit-finding work at X-Biotix we put together a multi-disciplinary team including Medicinal Chemistry, Computational Chemistry, Structural Biology and DMPK at our Abingdon UK site, in vitro and in vivo Microbiology and PK at our Alderley Park UK site, and in vitro Biology at our site in Hamburg, Germany. Through structure and property-based optimisation we were able to design highly potent inhibitors of Pseudomonas aeruginosa LpxA that were active against multi-drug resistant clinical isolates. To our knowledge, this is the first reported LpxA inhibitor series with selective activity against P. aeruginosa bacteria. In our paper in the Journal of Medicinal Chemistry we share the optimisation story, along with a significant quantity of activity data that we hope will be useful for other teams working on small molecule strategies to tackle P. aeruginosa and other Gram-negative bacteria.