A Time-Resolved FRET Assay Identifies a Small Molecule that Inhibits the Essential Bacterial Cell Wall Polymerase FtsW

Angew Chem Int Ed Engl. 2023 Jun 19;62(25):e202301522. doi: 10.1002/anie.202301522. Epub 2023 May 11.

Abstract

The peptidoglycan cell wall is essential for bacterial survival. To form the cell wall, peptidoglycan glycosyltransferases (PGTs) polymerize Lipid II to make glycan strands and then those strands are crosslinked by transpeptidases (TPs). Recently, the SEDS (for shape, elongation, division, and sporulation) proteins were identified as a new class of PGTs. The SEDS protein FtsW, which produces septal peptidoglycan during cell division, is an attractive target for novel antibiotics because it is essential in virtually all bacteria. Here, we developed a time-resolved Förster resonance energy transfer (TR-FRET) assay to monitor PGT activity and screened a Staphylococcus aureus lethal compound library for FtsW inhibitors. We identified a compound that inhibits S. aureus FtsW in vitro. Using a non-polymerizable Lipid II derivative, we showed that this compound competes with Lipid II for binding to FtsW. The assays described here will be useful for discovering and characterizing other PGT inhibitors.

Keywords: Antibiotics; Assay Development; Bacteria; High-Throughput Screening; Peptidoglycan.

Publication types

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

MeSH terms

  • Bacterial Proteins* / metabolism
  • Cell Wall / metabolism
  • Fluorescence Resonance Energy Transfer
  • Membrane Proteins / metabolism
  • Penicillin-Binding Proteins / metabolism
  • Peptidoglycan / metabolism
  • Peptidoglycan Glycosyltransferase* / metabolism
  • Staphylococcus aureus / metabolism

Substances

  • Bacterial Proteins
  • Penicillin-Binding Proteins
  • Peptidoglycan
  • Membrane Proteins
  • Peptidoglycan Glycosyltransferase