What is type VI secretion doing in all those bugs?

Trends Microbiol. 2010 Dec;18(12):531-7. doi: 10.1016/j.tim.2010.09.001. Epub 2010 Oct 18.


The identification of bacterial secretion systems capable of translocating substrates into eukaryotic cells via needle-like appendages has opened fruitful and exciting areas of microbial pathogenesis research. The recent discovery of the type VI secretion system (T6SS) was met with early speculation that it too acts as a 'needle' that pathogens aim at host cells. New reports demonstrate that certain T6SSs are potent mediators of interbacterial interactions. In light of these findings, we examined earlier data indicating its role in pathogenesis. We conclude that although T6S can, in rare instances, directly influence interactions with higher organisms, the broader physiological significance of the system is likely to provide defense against simple eukaryotic cells and other bacteria in the environment. The crucial role of T6S in bacterial interactions, along with its presence in many organisms relevant to disease, suggests that it might be a key determinant in the progression and outcome of certain human polymicrobial infections.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Bacteria / metabolism*
  • Bacteria / pathogenicity
  • Bacterial Infections / microbiology
  • Bacterial Proteins / metabolism
  • Bacterial Secretion Systems*
  • Gene Expression Regulation, Bacterial
  • Host-Pathogen Interactions
  • Humans


  • Bacterial Proteins
  • Bacterial Secretion Systems