Association of organic solvent tolerance and fluoroquinolone resistance in clinical isolates of Escherichia coli

J Antimicrob Chemother. 1998 Jan;41(1):111-4. doi: 10.1093/jac/41.1.111.


Fluoroquinolone resistance in Escherichia coli is principally caused by two kinds of mutation: those affecting the target proteins of the drugs, i.e. DNA gyrase and topoisomerase IV, and those affecting regulatory genes such as marA, soxS or robA. Recently, overexpression of the latter genes was linked to increased organic solvent tolerance in E. coli. Among 138 clinical fluoroquinolone-resistant and -susceptible clinical isolates of E. coli we found a high association between fluoroquinolone resistance and organic solvent tolerance. This finding suggests that E. coli may undergo an adaptive response to extrinsic substances other than quinolones, while mutating to fluoroquinolone resistance.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Anti-Infective Agents / pharmacology*
  • Cyclohexanes / pharmacology*
  • Drug Resistance, Microbial / genetics
  • Escherichia coli / drug effects*
  • Fluoroquinolones
  • Gene Expression Regulation, Bacterial
  • Genes, Bacterial / genetics*
  • Humans
  • Microbial Sensitivity Tests
  • Solvents / pharmacology*
  • Statistics as Topic


  • Anti-Infective Agents
  • Cyclohexanes
  • Fluoroquinolones
  • Solvents