Phosphotransfer signal transduction between two regulatory factors involved in the osmoregulated kdp operon in Escherichia coli

Mol Microbiol. 1992 Jul;6(13):1777-84. doi: 10.1111/j.1365-2958.1992.tb01350.x.


The proteins KdpD and KdpE are regulatory factors critically involved in the osmotic regulation of the kdpABC operon that is responsible for a high-affinity transport system in Escherichia coli. In this study, we obtained biochemical evidence supporting the view that the KdpD protein is a sensory protein kinase that exhibits autophosphorylation and KdpE-phosphotransfer characteristics. During the course of such studies we established a procedure for purifying the KdpE protein in large quantities. We also developed a procedure for preparing cytoplasmic membrane enriched with the KdpD protein that exhibits in vitro ability with regard to phosphorylation of KdpE protein.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Bacterial Proteins / genetics
  • Bacterial Proteins / isolation & purification
  • Bacterial Proteins / metabolism*
  • Biological Transport
  • Cell Membrane / metabolism
  • Escherichia coli / genetics*
  • Escherichia coli / metabolism
  • Escherichia coli Proteins*
  • Molecular Weight
  • Operon*
  • Osmolar Concentration
  • Phosphorylation
  • Potassium / metabolism*
  • Protein Kinases / genetics
  • Protein Kinases / isolation & purification
  • Protein Kinases / metabolism*
  • Signal Transduction*
  • Trans-Activators / genetics
  • Trans-Activators / isolation & purification
  • Trans-Activators / metabolism*


  • Bacterial Proteins
  • Escherichia coli Proteins
  • Trans-Activators
  • kdpE protein, E coli
  • KdpD protein, E coli
  • Protein Kinases
  • kdpD protein, Bacteria
  • Potassium