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Detection of Toxin Translocation into the Host Cytosol by Surface Plasmon Resonance
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Detection of Toxin Translocation into the Host Cytosol by Surface Plasmon Resonance

Published on: January 3, 2012

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Contact-dependent interbacterial toxins deliver a message

Erin C Garcia1

  • 1Department of Microbiology, Immunology, and Molecular Genetics, University of Kentucky, Lexington, KY 40536, United States.

Current Opinion in Microbiology
|October 28, 2017
PubMed

Insights

Bacteria use contact-dependent toxin delivery systems, like type VI secretion (T6S) and contact-dependent growth inhibition (CDI), for competition. Research reveals these systems also play non-competitive roles, suggesting broader functions in bacterial interactions.

Area of Science:

  • Microbiology
  • Bacterial Cell Biology
  • Molecular Biology

Background:

  • Gram-negative and Gram-positive bacteria possess contact-dependent systems for toxin delivery.
  • Type VI secretion (T6S) and contact-dependent growth inhibition (CDI) systems are key examples.
  • The in vitro role in interbacterial competition is established, but in vivo functions remain less understood.

Purpose of the Study:

  • To review recent insights into the mechanisms and biological roles of contact-dependent toxin delivery systems.
  • To explore functions beyond interbacterial competition, such as signal transduction.
  • To assess the prevalence of these diverse functions in bacterial interactions.

Main Methods:

  • Literature review of recent research on T6S and CDI systems.
  • Analysis of studies investigating toxin delivery mechanisms and activity.
  • Examination of research on contact-dependent toxin functions in relevant biological contexts.

Main Results:

  • Contact-dependent toxin delivery systems mediate interbacterial competition in vitro.
  • Recent studies provide insights into in vivo mechanisms and functions of these systems.
  • Non-competitive roles, including interbacterial signal transduction, have been identified.

Conclusions:

  • Contact-dependent toxin delivery systems have biological roles beyond interbacterial competition.
  • Functions such as signal transduction are increasingly recognized.
  • These multifaceted systems are likely more widespread than previously appreciated.

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