Recombination-deficient mutants of Salmonella typhimurium are avirulent and sensitive to the oxidative burst of macrophages

Mol Microbiol. 1993 Mar;7(6):933-6. doi: 10.1111/j.1365-2958.1993.tb01184.x.


Mutations in the genes recA and recBC were constructed in the virulent Salmonella typhimurium strain 14028s. Both the recA and recBC mutants were attenuated in mice. The mutants were also sensitive to killing by macrophages in vitro. The recombination mutants were no longer macrophage sensitive in a variant line of J774 macrophage-like cells that fail to generate superoxide. This suggests that repair of DNA damage by Salmonella is necessary for full virulence in vivo and that the oxidative burst of phagocytes is one source of such DNA damage.

Publication types

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

MeSH terms

  • Animals
  • Bacterial Proteins / genetics*
  • DNA Damage
  • DNA, Bacterial / genetics
  • Escherichia coli Proteins*
  • Exodeoxyribonuclease V
  • Exodeoxyribonucleases / genetics*
  • Female
  • Macrophages / physiology*
  • Mice
  • Mice, Inbred BALB C
  • Mitomycins / pharmacology
  • Rec A Recombinases / genetics*
  • Recombination, Genetic / genetics*
  • Respiratory Burst*
  • Salmonella typhimurium / drug effects
  • Salmonella typhimurium / genetics*
  • Salmonella typhimurium / pathogenicity
  • Superoxides / metabolism
  • Virulence / genetics


  • Bacterial Proteins
  • DNA, Bacterial
  • Escherichia coli Proteins
  • Mitomycins
  • Superoxides
  • Rec A Recombinases
  • Exodeoxyribonucleases
  • Exodeoxyribonuclease V
  • exodeoxyribonuclease V, E coli