Selection and Identification of Novel Antibacterial Agents against Planktonic Growth and Biofilm Formation of Enterococcus faecalis

J Med Chem. 2021 Oct 28;64(20):15037-15052. doi: 10.1021/acs.jmedchem.1c00939. Epub 2021 Oct 16.

Abstract

YycFG, one of the two-component systems involved in the regulation of biofilm formation, has attracted increasing interest as a potential target of antibacterial and antibiofilm agents. YycG inhibitors for Staphylococcus aureus and Staphylococcus epidermidis have been developed, but Enterococcus faecalis remains underexplored. Herein, we selected and identified novel candidate molecules against E. faecalis targeting histidine kinase YycG using high-throughput virtual screening; six molecules (compound-16, -30, -42, -46, -59, and -62) with low cytotoxicity toward mammalian cells were verified as potential YycG inhibitors through an autophosphorylation test and binding kinetics. Compound-16 inhibited planktonic cells of E. faecalis, including the vancomycin- or linezolid-resistant strains. In contrast, compound-62 did not affect planktonic growth but significantly inhibited biofilm formation in static and dynamic conditions. Compound-62 combined with ampicillin could synergistically eradicate the biofilm-embedded viable bacteria. The study demonstrates that YycG inhibitors may be valuable approaches for the development of novel antimicrobial agents for difficult-to-treat bacterial infections.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Anti-Bacterial Agents / chemistry
  • Anti-Bacterial Agents / pharmacology*
  • Biofilms / drug effects*
  • Cell Survival / drug effects
  • Chlorocebus aethiops
  • Dose-Response Relationship, Drug
  • Enterococcus faecalis / drug effects*
  • Enterococcus faecalis / growth & development
  • Erythrocytes / drug effects
  • Humans
  • Microbial Sensitivity Tests
  • Molecular Structure
  • Structure-Activity Relationship
  • Vero Cells

Substances

  • Anti-Bacterial Agents