RcsCDB His-Asp phosphorelay system negatively regulates the flhDC operon in Escherichia coli

Mol Microbiol. 2003 Aug;49(3):823-32. doi: 10.1046/j.1365-2958.2003.03601.x.


The genes involved in flagellum synthesis, motility and chemotaxis in Escherichia coli are expressed in a hierarchical fashion. At the top of the hierarchy lies the master regulator FlhDC, required for the expression of the whole set of genes. The operon flhDC is controlled by numerous regulators including H-NS, CRP, EnvZ/OmpR, QseBC and LrhA. In the present work, we report that the flhDC operon is also negatively regulated by the His-Asp phosphorelay system RcsCDB. The regulation is potentiated by the RcsB cofactor RcsA. Genetic analysis indicates that an RcsAB box, located downstream of the promoter, is required for the regulation. The binding of RcsB and RcsA to this site was demonstrated by gel retardation and DNase I protection assays. In addition, mutation analysis suggests that RcsA-specific determinants lie in the right part of the 'RcsAB box'.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Bacterial Proteins / physiology*
  • Base Sequence
  • DNA Footprinting
  • DNA Mutational Analysis
  • DNA, Bacterial / genetics
  • DNA-Binding Proteins / biosynthesis
  • DNA-Binding Proteins / genetics*
  • Electrophoretic Mobility Shift Assay
  • Escherichia coli / genetics*
  • Escherichia coli Proteins / biosynthesis
  • Escherichia coli Proteins / genetics
  • Escherichia coli Proteins / physiology*
  • Flagella / metabolism
  • Gene Expression Regulation, Bacterial / physiology*
  • Molecular Sequence Data
  • Multienzyme Complexes / physiology*
  • Operon / genetics
  • Phosphoprotein Phosphatases / physiology*
  • Phosphotransferases / physiology*
  • Promoter Regions, Genetic
  • Protein Kinases / physiology*
  • Regulatory Sequences, Nucleic Acid
  • Trans-Activators / biosynthesis
  • Trans-Activators / genetics*
  • Transcription Factors*
  • Transcription, Genetic


  • Bacterial Proteins
  • DNA, Bacterial
  • DNA-Binding Proteins
  • Escherichia coli Proteins
  • Multienzyme Complexes
  • RcsB protein, E coli
  • Trans-Activators
  • Transcription Factors
  • flhC protein, E coli
  • flhD protein, E coli
  • rcsC protein, E coli
  • RcsB protein, Bacteria
  • RcsA protein, E coli
  • Phosphotransferases
  • Protein Kinases
  • rcsD protein, E coli
  • Phosphoprotein Phosphatases