Coupling Novel Probes with Molecular Localization Microscopy Reveals Cell Wall Homeostatic Mechanisms in Staphylococcus aureus

ACS Chem Biol. 2022 Dec 16;17(12):3298-3305. doi: 10.1021/acschembio.2c00741. Epub 2022 Nov 22.

Abstract

Bacterial cell wall peptidoglycan is essential for viability, and its synthesis is targeted by antibiotics, including penicillin. To determine how peptidoglycan homeostasis controls cell architecture, growth, and division, we have developed novel labeling approaches. These are compatible with super-resolution fluorescence microscopy to examine peptidoglycan synthesis, hydrolysis, and the localization of the enzymes required for its biosynthesis (penicillin binding proteins (PBPs)). Synthesis of a cephalosporin-based fluorescent probe revealed a pattern of PBPs at the septum during division, supporting a model of dispersed peptidoglycan synthesis. Metabolic and hydroxylamine-based probes respectively enabled the synthesis of glycan strands and associated reducing termini of the peptidoglycan to be mapped. Foci and arcs of reducing termini appear as a result of both synthesis of glycan strands and glucosaminidase activity of the major peptidoglycan hydrolase, SagB. Our studies provide molecular level details of how essential peptidoglycan dynamics are controlled during growth and division.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Bacterial Proteins / metabolism
  • Cell Wall / metabolism
  • Homeostasis
  • Humans
  • Microscopy, Fluorescence
  • Penicillin-Binding Proteins / metabolism
  • Peptidoglycan / metabolism
  • Staphylococcal Infections* / metabolism
  • Staphylococcus aureus*

Substances

  • Peptidoglycan
  • Penicillin-Binding Proteins
  • Bacterial Proteins