PprA: a novel protein from Deinococcus radiodurans that stimulates DNA ligation

Mol Microbiol. 2004 Oct;54(1):278-85. doi: 10.1111/j.1365-2958.2004.04272.x.


The extraordinary radiation resistance of Deinococcus radiodurans results from the efficient capacity of the bacterium to repair DNA double-strand breaks. By analysing the DNA damage repair-deficient mutant, KH311, a unique radiation-inducible gene (designated pprA) responsible for loss of radiation resistance was identified. Investigations in vitro showed that the gene product of pprA (PprA) preferentially bound to double-stranded DNA carrying strand breaks, inhibited Escherichia coli exonuclease III activity, and stimulated the DNA end-joining reaction catalysed by ATP-dependent and NAD-dependent DNA ligases. These results suggest that D. radiodurans has a radiation-induced non-homologous end-joining repair mechanism in which PprA plays a critical role.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Sequence
  • Bacterial Proteins / chemistry
  • Bacterial Proteins / genetics
  • Bacterial Proteins / metabolism*
  • Base Sequence
  • DNA / genetics
  • DNA / metabolism
  • DNA Damage
  • DNA Ligases / genetics
  • DNA Ligases / metabolism*
  • DNA Repair*
  • DNA, Bacterial / genetics
  • DNA, Bacterial / metabolism
  • Deinococcus / genetics
  • Deinococcus / metabolism*
  • Deinococcus / radiation effects
  • Gene Expression Regulation, Bacterial*
  • Molecular Sequence Data
  • Mutation
  • Rec A Recombinases / metabolism


  • Bacterial Proteins
  • DNA, Bacterial
  • DNA
  • Rec A Recombinases
  • DNA Ligases