Increasing the permeability of Escherichia coli using MAC13243

Sci Rep. 2017 Dec 15;7(1):17629. doi: 10.1038/s41598-017-17772-6.


The outer membrane of gram-negative bacteria is a permeability barrier that prevents the efficient uptake of molecules with large scaffolds. As a consequence, a number of antibiotic classes are ineffective against gram-negative strains. Herein we carried out a high throughput screen for small molecules that make the outer membrane of Escherichia coli more permeable. We identified MAC13243, an inhibitor of the periplasmic chaperone LolA that traffics lipoproteins from the inner to the outer membrane. We observed that cells were (1) more permeable to the fluorescent probe 1-N-phenylnapthylamine, and (2) more susceptible to large-scaffold antibiotics when sub-inhibitory concentrations of MAC13243 were used. To exclude the possibility that the permeability was caused by an off-target effect, we genetically reconstructed the MAC13243-phenotype by depleting LolA levels using the CRISPRi system.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • 1-Naphthylamine / analogs & derivatives
  • 1-Naphthylamine / metabolism
  • Anti-Bacterial Agents / pharmacology*
  • Cell Membrane / drug effects*
  • Cell Membrane Permeability / drug effects*
  • Escherichia coli / genetics
  • Escherichia coli / metabolism*
  • Escherichia coli Proteins / antagonists & inhibitors*
  • Escherichia coli Proteins / genetics
  • High-Throughput Screening Assays
  • Microbial Sensitivity Tests
  • Periplasmic Binding Proteins / antagonists & inhibitors*
  • Periplasmic Binding Proteins / genetics
  • Triazines / pharmacology*
  • Vancomycin / pharmacology*


  • Anti-Bacterial Agents
  • Escherichia coli Proteins
  • LolA protein, E coli
  • MAC13243
  • Periplasmic Binding Proteins
  • Triazines
  • Vancomycin
  • N-phenyl-1-naphthylamine
  • 1-Naphthylamine