The type VI secretion system of Vibrio cholerae fosters horizontal gene transfer

Science. 2015 Jan 2;347(6217):63-7. doi: 10.1126/science.1260064.


Natural competence for transformation is a common mode of horizontal gene transfer and contributes to bacterial evolution. Transformation occurs through the uptake of external DNA and its integration into the genome. Here we show that the type VI secretion system (T6SS), which serves as a predatory killing device, is part of the competence regulon in the naturally transformable pathogen Vibrio cholerae. The T6SS-encoding gene cluster is under the positive control of the competence regulators TfoX and QstR and is induced by growth on chitinous surfaces. Live-cell imaging revealed that deliberate killing of nonimmune cells via competence-mediated induction of T6SS releases DNA and makes it accessible for horizontal gene transfer in V. cholerae.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Bacterial Proteins / genetics
  • Bacterial Proteins / physiology
  • Bacterial Secretion Systems / genetics*
  • DNA Transformation Competence*
  • Gene Transfer, Horizontal*
  • Multigene Family
  • Trans-Activators / genetics
  • Trans-Activators / physiology
  • Vibrio cholerae / genetics*
  • Vibrio cholerae / physiology*


  • Bacterial Proteins
  • Bacterial Secretion Systems
  • Trans-Activators