Gene Regulation by Phosphate in Enteric Bacteria

J Cell Biochem. 1993 Jan;51(1):47-54. doi: 10.1002/jcb.240510110.


The Escherichia coli phosphate (PHO) regulon includes 31 (or more) genes arranged in eight separate operons. All are coregulated by environmental (extra-cellular) phosphate and are probably involved in phosphorus assimilation. Pi control of these genes requires the sensor PhoR, the response regulator PhoB, the binding protein-dependent Pi-specific transporter Pst, and the accessory protein PhoU. During Pi limitation, PhoR turns on genes of the PHO regulon by phosphorylating PhoB that in turn activates transcription by binding to promoters that share an 18-base consensus PHO Box. When Pi is in excess, PhoR, Pst, and PhoU together turn off the PHO regulon, presumably by dephosphorylating PhoB. In addition, two Pi-independent controls that may be forms of cross regulation turn on the PHO regulon in the absence of PhoR. The sensor CreC, formerly called PhoM, phosphorylates PhoB in response to some (unknown) catabolite, while acetyl phosphate may directly phosphorylate PhoB. Cross regulation of the PHO regulon by CreC and acetyl phosphate may be examples of underlying control mechanisms important for the general (global) control of cell growth and metabolism.

Publication types

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

MeSH terms

  • Adenosine Triphosphate / metabolism
  • Bacterial Proteins / genetics
  • Bacterial Proteins / metabolism*
  • Base Sequence
  • Biological Transport
  • Consensus Sequence
  • Energy Metabolism
  • Escherichia coli / genetics*
  • Escherichia coli / metabolism
  • Gene Expression Regulation, Bacterial* / drug effects
  • Genes, Bacterial
  • Models, Biological
  • Molecular Sequence Data
  • Operon*
  • Phosphates / physiology*
  • Phosphorylation
  • Promoter Regions, Genetic
  • Protein Processing, Post-Translational
  • Signal Transduction*
  • Transcription Factors / genetics
  • Transcription Factors / metabolism


  • Bacterial Proteins
  • Phosphates
  • Transcription Factors
  • PhoB protein, Bacteria
  • Adenosine Triphosphate