Interbacterial predation as a strategy for DNA acquisition in naturally competent bacteria

Nat Rev Microbiol. 2017 Oct;15(10):621-629. doi: 10.1038/nrmicro.2017.66. Epub 2017 Jul 10.

Abstract

Natural competence enables bacteria to take up exogenous DNA. The evolutionary function of natural competence remains controversial, as imported DNA can act as a source of substrates or can be integrated into the genome. Exogenous homologous DNA can also be used for genome repair. In this Opinion article, we propose that predation of non-related neighbouring bacteria coupled with competence regulation might function as an active strategy for DNA acquisition. Competence-dependent kin-discriminated killing has been observed in the unrelated bacteria Vibrio cholerae and Streptococcus pneumoniae. Importantly, both the regulatory networks and the mode of action of neighbour predation differ between these organisms, with V. cholerae using a type VI secretion system and S. pneumoniae secreting bacteriocins. We argue that the forced release of DNA from killed bacteria and the transfer of non-clonal genetic material have important roles in bacterial evolution.

Publication types

  • Review

MeSH terms

  • Biological Transport
  • DNA Transformation Competence / genetics*
  • DNA, Bacterial / genetics*
  • Gene Expression Regulation, Bacterial
  • Gene Transfer, Horizontal / genetics*
  • Streptococcus pneumoniae / genetics*
  • Transformation, Bacterial / genetics*
  • Type VI Secretion Systems / genetics
  • Vibrio cholerae / genetics*

Substances

  • DNA, Bacterial
  • Type VI Secretion Systems