Project Summary/Abstract An alarming number of Gram-negative nosocomial pathogens have acquired resistance to nearly all currently available antibiotics, making it very difficult to treat patients effectively. Moreover, in the last decade, only a handful of new antimicrobial agents have been introduced, and these have mostly targeted drug-resistant Gram-positive pathogens such as methicillin-resistant S. aureus (MRSA) and vancomycin-resistant enterococci (VRE). The goal of this proposal is to develop a high-throughput screening assay to discover and validate small molecule inhibitors of LpxH, an essential enzyme in the lipid A biosynthetic pathway, as novel antibiotics for the treatment of infections caused by multidrug-resistant Gram-negative pathogens.