Transition-state regulators: sentinels of Bacillus subtilis post-exponential gene expression

Mol Microbiol. 1993 Feb;7(3):337-42. doi: 10.1111/j.1365-2958.1993.tb01125.x.


When Bacillus subtilis encounters a nutrient-depleted environment, it expresses a wide variety of genes that encode functions in alternative pathways of metabolism and energy production. Expression of these genes first occurs during the transition from active growth into stationary phase and is controlled by a class of proteins termed transition-state regulators. In several instances, a given gene is redundantly controlled by two or more of these regulators and many of these regulators control genes in numerous different pathways. The AbrB, Hpr and Sin proteins are the best-studied examples of these regulatory molecules. Their role is to prevent inappropriate and possibly detrimental functions from being expressed during exponential growth when they are not needed. They serve as elements integrating sporulation with ancillary stationary-phase phenomena and appear to participate in the timing of early sporulation events and in fine-tuning the magnitude of gene expression in response to specific environmental conditions.

Publication types

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

MeSH terms

  • Bacillus subtilis / genetics*
  • Bacillus subtilis / growth & development
  • Bacillus subtilis / metabolism
  • Bacterial Proteins / genetics
  • Cell Division
  • DNA-Binding Proteins / genetics
  • Gene Expression Regulation, Bacterial*
  • Genes, Bacterial / genetics*
  • Genes, Regulator / genetics*
  • Phosphoenolpyruvate Sugar Phosphotransferase System / genetics
  • Repressor Proteins / genetics
  • Transcription Factors / genetics


  • AbrB protein, Bacillus subtilis
  • Bacterial Proteins
  • DNA-Binding Proteins
  • Repressor Proteins
  • Transcription Factors
  • Phosphoenolpyruvate Sugar Phosphotransferase System
  • phosphocarrier protein HPr