Prokaryotic 2-component Systems and the OmpR/PhoB Superfamily

Can J Microbiol. 2015 Nov;61(11):799-810. doi: 10.1139/cjm-2015-0345. Epub 2015 Aug 21.


In bacteria, 2-component regulatory systems (TCSs) are the critical information-processing pathways that link stimuli to specific adaptive responses. Signals perceived by membrane sensors, which are generally histidine kinases, are transmitted by response regulators (RRs) to allow cells to cope rapidly and effectively with environmental challenges. Over the past few decades, genes encoding components of TCSs and their responsive proteins have been identified, crystal structures have been described, and signaling mechanisms have been elucidated. Here, we review recent findings and interesting breakthroughs in bacterial TCS research. Furthermore, we discuss structural features, mechanisms of activation and regulation, and cross-regulation of RRs, with a focus on the largest RR family, OmpR/PhoB, to provide a comprehensive overview of these critically important signaling molecules.

Keywords: 2-component system; OmpR/PhoB family; bacterial signal transduction; famille OmpR/PhoB; response regulator; régulateurs de réponse; système à 2 composants; transduction de signal chez les bactéries.

Publication types

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

MeSH terms

  • Bacillus subtilis / metabolism
  • Bacterial Proteins / metabolism*
  • Cell Membrane / enzymology
  • DNA / chemistry
  • Escherichia coli / metabolism
  • Gene Expression Regulation, Bacterial*
  • Histidine Kinase
  • Phosphorylation
  • Protein Binding
  • Protein Kinases / metabolism
  • Protein Structure, Secondary
  • Protein Structure, Tertiary
  • Signal Transduction*
  • Trans-Activators / metabolism*


  • Bacterial Proteins
  • Trans-Activators
  • osmolarity response regulator proteins
  • PhoB protein, Bacteria
  • DNA
  • Protein Kinases
  • Histidine Kinase