Bacterial sensors of oxygen

Curr Opin Microbiol. 2009 Apr;12(2):145-51. doi: 10.1016/j.mib.2009.01.008. Epub 2009 Feb 24.


The concentration of molecular oxygen (O(2)) began to increase in the Earth's atmosphere approximately two billion years ago. Its presence posed a threat to anaerobes but also offered opportunities for improved energy conservation via aerobic respiration. The ability to sense environmental O(2) thus became, and remains, important for many bacteria, both for protection and switching between anaerobic and aerobic respiration. Utilizing an iron-sulfur cluster as the sensor of O(2) exploits the ability of O(2) to oxidize the iron-sulfur cluster, ultimately resulting in cluster disassembly. When utilizing heme as the sensor, the capacity of O(2) to form a reversible Fe-O(2) bond or alternatively the oxidation of the heme iron atom itself is used to detect O(2) and switch regulators between active and inactive forms.

Publication types

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

MeSH terms

  • Bacterial Physiological Phenomena*
  • Bacterial Proteins / physiology*
  • Escherichia coli Proteins / physiology
  • Hemeproteins / physiology*
  • Histidine Kinase
  • Iron-Sulfur Proteins / physiology*
  • Oxygen / metabolism*


  • Bacterial Proteins
  • Escherichia coli Proteins
  • FNR protein, E coli
  • Hemeproteins
  • Iron-Sulfur Proteins
  • FixL protein, Bacteria
  • Histidine Kinase
  • Oxygen