Sensing external stress: watchdogs of the Escherichia coli cell envelope

Curr Opin Microbiol. 2005 Apr;8(2):122-6. doi: 10.1016/j.mib.2005.02.013.


The Cpx and sigmaE signaling systems monitor the cell envelope in Escherichia coli. When induced, each system triggers a signaling cascade that leads to the upregulation of factors needed to combat envelope damage. Although each system is distinct and can be uniquely induced by certain cues, they also share striking similarities. In this review, we discuss the recent progress in our understanding of the Cpx and sigmaE systems and compare how both function to maintain the integrity of the cell envelope.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, U.S. Gov't, P.H.S.
  • Review

MeSH terms

  • Adaptation, Physiological*
  • Bacterial Proteins / physiology
  • Cell Membrane / physiology
  • Escherichia coli / genetics
  • Escherichia coli / physiology*
  • Escherichia coli Proteins / physiology*
  • Gene Expression Regulation, Bacterial*
  • Protein Kinases / physiology
  • Sigma Factor / physiology
  • Signal Transduction*
  • Transcription Factors / physiology


  • Bacterial Proteins
  • Escherichia coli Proteins
  • Sigma Factor
  • Transcription Factors
  • sporulation-specific sigma factors
  • CpxR protein, Bacteria
  • Protein Kinases
  • CpxA protein, E coli