Feedback Control of Two-Component Regulatory Systems

Annu Rev Microbiol. 2016 Sep 8;70:103-24. doi: 10.1146/annurev-micro-102215-095331.


Two-component systems are a dominant form of bacterial signal transduction. The prototypical two-component system consists of a sensor that responds to a specific input(s) by modifying the output of a cognate regulator. Because the output of a two-component system is the amount of phosphorylated regulator, feedback mechanisms may alter the amount of regulator, and/or modify the ability of a sensor or other proteins to alter the phosphorylation state of the regulator. Two-component systems may display intrinsic feedback whereby the amount of phosphorylated regulator changes under constant inducing conditions and without the participation of additional proteins. Feedback control allows a two-component system to achieve particular steady-state levels, to reach a given steady state with distinct dynamics, to express coregulated genes in a given order, and to activate a regulator to different extents, depending on the signal acting on the sensor.

Keywords: expression dynamics; phosphorylation; signal access; transcription surge.

Publication types

  • Review

MeSH terms

  • Bacteria / genetics*
  • Bacteria / metabolism
  • Bacterial Proteins / genetics
  • Bacterial Proteins / metabolism*
  • Feedback, Physiological
  • Gene Expression Regulation, Bacterial*
  • Signal Transduction


  • Bacterial Proteins