Identification of a DNA non-homologous end-joining complex in bacteria

Geoffrey R. Weller, Boris Kysela, Rajat Roy, Louise M. Tonkin, Elizabeth Scanlan, Marina Della, Susanne Krogh Devine, Jonathan P. Day, Adam Wilkinson, Fabrizio d'Adda di Fagagna, Kevin M. Devine, Richard P. Bowater, Penny A. Jeggo, Stephen P. Jackson, Aidan J. Doherty

Research output: Contribution to journalArticlepeer-review

263 Citations (Scopus)


In eukaryotic cells, double-strand breaks (DSBs) in DNA are generally repaired by the pathway of homologous recombination or by DNA nonhomologous end joining (NHEJ). Both pathways have been highly conserved throughout eukaryotic evolution, but no equivalent NHEJ system has been identified in prokaryotes. The NHEJ pathway requires a DNA end-binding component called Ku. We have identified bacterial Ku homologs and show that these proteins retain the biochemical characteristics of the eukaryotic Ku heterodimer. Furthermore, we show that bacterial Ku specifically recruits DNA ligase to DNA ends and stimulates DNA ligation. Loss of these proteins leads to hypersensitivity to ionizing radiation in Bacillus subtilis. These data provide evidence that many bacteria possess a DNA DSB repair apparatus that shares many features with the NHEJ system of eukarya and suggest that this DNA repair pathway arose before the prokaryotic and eukaryotic lineages diverged.
Original languageEnglish
Pages (from-to)1686-1689
Number of pages4
Issue number5587
Publication statusPublished - 2002

Cite this