Mechanistic Studies and In Vivo Efficacy of an Oxadiazole-Containing Antibiotic

J Med Chem. 2022 May 12;65(9):6612-6630. doi: 10.1021/acs.jmedchem.1c02034. Epub 2022 Apr 28.

Abstract

Methicillin-resistant Staphylococcus aureus (MRSA) infections are still difficult to treat, despite the availability of many FDA-approved antibiotics. Thus, new compound scaffolds are still needed to treat MRSA. The oxadiazole-containing compound, HSGN-94, has been shown to reduce lipoteichoic acid (LTA) in S. aureus, but the mechanism that accounts for LTA biosynthesis inhibition remains uncharacterized. Herein, we report the elucidation of the mechanism by which HSGN-94 inhibits LTA biosynthesis via utilization of global proteomics, activity-based protein profiling, and lipid analysis via multiple reaction monitoring (MRM). Our data suggest that HSGN-94 inhibits LTA biosynthesis via direct binding to PgcA and downregulation of PgsA. We further show that HSGN-94 reduces the MRSA load in skin infection (mouse) and decreases pro-inflammatory cytokines in MRSA-infected wounds. Collectively, HSGN-94 merits further consideration as a potential drug for staphylococcal infections.

Publication types

  • Research Support, N.I.H., Extramural

MeSH terms

  • Animals
  • Anti-Bacterial Agents / chemistry
  • Methicillin-Resistant Staphylococcus aureus*
  • Mice
  • Microbial Sensitivity Tests
  • Oxadiazoles / metabolism
  • Oxadiazoles / pharmacology
  • Oxadiazoles / therapeutic use
  • Staphylococcal Infections* / drug therapy
  • Staphylococcus aureus

Substances

  • Anti-Bacterial Agents
  • Oxadiazoles