A novel DNA-binding protein with regulatory and protective roles in starved Escherichia coli

Genes Dev. 1992 Dec;6(12B):2646-54. doi: 10.1101/gad.6.12b.2646.

Abstract

A starvation-inducible DNA-binding protein was discovered as a result of the analysis of proteins synthesized in 3-day-old cultures of Escherichia coli. This 19-kD protein, designated Dps, is abundant in starved cells. In vitro, Dps forms extremely stable complexes with DNA, without apparent sequence specificity. When complexed with Dps, DNA is rendered DNase resistant. Mutant cells lacking Dps show dramatic changes in the pattern of proteins synthesized during starvation. The mutants also fail to develop starvation-induced resistance to hydrogen peroxide, an agent that can cause oxidative damage to DNA in vivo. These results have prompted us to postulate that Dps plays an important role both in gene expression and DNA protection during stationary phase. The existence of similar proteins, heretofore with no known function, in bacterial species distantly related to Escherichia coli suggests that Dps may define a novel class of widely conserved DNA-binding proteins.

Publication types

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

MeSH terms

  • Amino Acid Sequence
  • Bacterial Proteins / biosynthesis
  • Bacterial Proteins / isolation & purification
  • Bacterial Proteins / metabolism*
  • DNA, Bacterial / metabolism
  • DNA, Superhelical / metabolism
  • DNA-Binding Proteins / biosynthesis
  • DNA-Binding Proteins / isolation & purification
  • DNA-Binding Proteins / metabolism*
  • Electrophoresis, Gel, Two-Dimensional
  • Electrophoresis, Polyacrylamide Gel
  • Escherichia coli / genetics
  • Escherichia coli / growth & development
  • Escherichia coli / metabolism*
  • Hydrogen Peroxide / pharmacology
  • Kinetics
  • Microscopy, Electron
  • Molecular Sequence Data
  • Mutation
  • Phenotype

Substances

  • Bacterial Proteins
  • DNA, Bacterial
  • DNA, Superhelical
  • DNA-Binding Proteins
  • DPS protein, Bacteria
  • Hydrogen Peroxide