Sub-lethal Concentrations of Phytochemicals (Carvacrol and Oregano) Select for Reduced Susceptibility Mutants of Escherichia coli O23:H52

Pol J Microbiol. 2020;69(1):1-5. doi: 10.33073/pjm-2020-003.

Abstract

In vitro studies aimed at studying the mechanism of action of carvacrol and oregano as natural anti-bacterial agents to control multiple antibiotic-resistant avian pathogenic Escherichia coli (APEC) strain O23:H52 isolated from chicken were performed. Derivatives with increased minimum inhibitory concentrations (MIC) to the phytochemicals were selected after growing Escherichia coli (E. coli) strain O23:H52 at sub-lethal concentrations of carvacrol and oregano for a period of 60 days. Whole-genome sequencing (WGS) of two derivatives revealed a missense mutation in cadC and marR: the genes responsible for survival mechanisms and antibiotic resistance by efflux, respectively.

In vitro studies aimed at studying the mechanism of action of carvacrol and oregano as natural anti-bacterial agents to control multiple antibiotic-resistant avian pathogenic Escherichia coli (APEC) strain O23:H52 isolated from chicken were performed. Derivatives with increased minimum inhibitory concentrations (MIC) to the phytochemicals were selected after growing Escherichia coli (E. coli) strain O23:H52 at sub-lethal concentrations of carvacrol and oregano for a period of 60 days. Whole-genome sequencing (WGS) of two derivatives revealed a missense mutation in cadC and marR: the genes responsible for survival mechanisms and antibiotic resistance by efflux, respectively.

MeSH terms

  • Animals
  • Anti-Bacterial Agents / pharmacology*
  • Chickens / microbiology
  • Cymenes / pharmacology*
  • Drug Resistance, Multiple, Bacterial
  • Escherichia coli / drug effects*
  • Escherichia coli / genetics
  • Escherichia coli Proteins / genetics
  • Microbial Sensitivity Tests
  • Mutation, Missense
  • Oils, Volatile / pharmacology
  • Origanum / chemistry*
  • Phytochemicals / pharmacology*
  • Repressor Proteins / genetics
  • Trans-Activators / genetics
  • Whole Genome Sequencing

Substances

  • Anti-Bacterial Agents
  • CadC protein, E coli
  • Cymenes
  • Escherichia coli Proteins
  • MarR protein, E coli
  • Oils, Volatile
  • Phytochemicals
  • Repressor Proteins
  • Trans-Activators
  • carvacrol