In vitro and in silico analysis of the efficiency of tetrahydropyridines as drug efflux inhibitors in Escherichia coli

Int J Antimicrob Agents. 2017 Mar;49(3):308-314. doi: 10.1016/j.ijantimicag.2016.11.024. Epub 2017 Jan 30.

Abstract

The objectives of this study were to evaluate tetrahydropyridine derivatives as efflux inhibitors and to understand the mechanism of action of the compounds by in silico studies. Minimum inhibitory concentration (MIC) determination, fluorometric methods and docking simulations were performed. The compounds NUNL02, NUNL09 and NUNL10 inhibited efflux, and NUNL02 is very likely a substrate of the transporter protein AcrB. Docking studies suggested that the mechanism of action could be by competition with substrate for binding sites and protein residues. We showed for the first time the potential of tetrahydropyridines as efflux inhibitors and highlighted compound NUNL02 as an AcrB-specific inhibitor. Docking studies suggested that competition is the putative mechanism of action of these compounds.

Keywords: AcrB; Competition; Efflux; Inhibitors.

MeSH terms

  • Anti-Bacterial Agents / chemistry
  • Anti-Bacterial Agents / metabolism*
  • Biological Transport, Active / drug effects*
  • Enzyme Inhibitors / chemistry
  • Enzyme Inhibitors / metabolism*
  • Escherichia coli / drug effects*
  • Escherichia coli Proteins / chemistry
  • Escherichia coli Proteins / metabolism*
  • Microbial Sensitivity Tests
  • Molecular Docking Simulation
  • Multidrug Resistance-Associated Proteins / chemistry
  • Multidrug Resistance-Associated Proteins / metabolism*
  • Protein Binding
  • Pyridines / chemistry
  • Pyridines / metabolism*

Substances

  • AcrB protein, E coli
  • Anti-Bacterial Agents
  • Enzyme Inhibitors
  • Escherichia coli Proteins
  • Multidrug Resistance-Associated Proteins
  • Pyridines