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Related Experiment Video

Updated: Jun 7, 2026

A Visual Assay to Monitor T6SS-mediated Bacterial Competition

A Visual Assay to Monitor T6SS-mediated Bacterial Competition

Published on: March 20, 2013

What is type VI secretion doing in all those bugs?

Sandra Schwarz¹, Rachel D Hood, Joseph D Mougous

¹Department of Microbiology, University of Washington, Seattle, WA 98195, USA.

Trends in Microbiology

|October 22, 2010

Summary

The type VI secretion system (T6SS) primarily functions in bacterial defense and interbacterial competition, rather than directly attacking host cells. Its role in polymicrobial infections highlights its significance in microbial pathogenesis.

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A Visual Assay to Monitor T6SS-mediated Bacterial Competition

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Area of Science:

Microbiology
Molecular Biology
Pathogenesis Research

Background:

Bacterial secretion systems translocate substrates into eukaryotic cells.
The type VI secretion system (T6SS) was initially investigated for potential roles in host cell pathogenesis.
Recent findings suggest T6SS has significant roles in interbacterial interactions.

Purpose of the Study:

To re-evaluate the role of the type VI secretion system (T6SS) in pathogenesis.
To understand the broader physiological significance of T6SS.
To investigate T6SS's role in interbacterial interactions and host-microbe dynamics.

Main Methods:

Review of existing literature on T6SS function.
Analysis of data concerning T6SS interactions with eukaryotic cells and bacteria.
Comparative analysis of T6SS presence in disease-relevant organisms.

Main Results:

T6SS is a potent mediator of interbacterial interactions.
Direct pathogenic effects of T6SS on higher organisms are rare.
T6SS primarily functions in defense against eukaryotic cells and other bacteria.

Conclusions:

The primary role of T6SS is likely environmental defense and bacterial competition.
T6SS can influence interactions with higher organisms in specific cases.
T6SS is a key factor in human polymicrobial infections due to its prevalence and function.