Inhibition of RecA protein by the Escherichia coli RecX protein: modulation by the RecA C terminus and filament functional state

J Biol Chem. 2004 Dec 17;279(51):52991-7. doi: 10.1074/jbc.M409050200. Epub 2004 Oct 4.

Abstract

The RecX protein is a potent inhibitor of RecA activities. We identified several factors that affect RecX-RecA interaction. The interaction is enhanced by the RecA C terminus and by significant concentrations of free Mg(2+) ion. The interaction is also enhanced by an N-terminal His(6) tag on the RecX protein. We conclude that RecX protein interacts most effectively with a RecA functional state designated A(o) and that the RecA C terminus has a role in modulating the interaction. We further identified a C-terminal point mutation in RecA protein (E343K) that significantly alters the interaction between RecA and RecX proteins.

Publication types

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

MeSH terms

  • Adenosine Triphosphatases / chemistry
  • Adenosine Triphosphate / chemistry
  • Bacterial Proteins / chemistry
  • Bacterial Proteins / physiology*
  • Buffers
  • Cloning, Molecular
  • DNA / chemistry
  • DNA, Single-Stranded / chemistry
  • Electrophoresis, Polyacrylamide Gel
  • Escherichia coli / metabolism
  • Escherichia coli / physiology*
  • Escherichia coli Proteins / physiology
  • Gene Expression Regulation, Bacterial
  • Hydrolysis
  • Ions
  • Magnesium / chemistry
  • Point Mutation
  • Protein Structure, Tertiary
  • Rec A Recombinases / antagonists & inhibitors*
  • Rec A Recombinases / chemistry
  • Time Factors

Substances

  • Bacterial Proteins
  • Buffers
  • DNA, Single-Stranded
  • Escherichia coli Proteins
  • Ions
  • RecX protein, Xanthomonas campestris
  • Adenosine Triphosphate
  • DNA
  • Rec A Recombinases
  • Adenosine Triphosphatases
  • Magnesium