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A functional VipA-VipB interaction is required for the type VI secretion system activity of Vibrio cholerae O1 strain A1552.

ABSTRACT:

Background

Many Gram-negative bacteria rely on a type VI secretion system (T6SS) to infect eukaryotic cells or to compete against other microbes. Common to these systems is the presence of two conserved proteins, in Vibrio cholerae denoted VipA and VipB, which have been shown to interact in many clinically relevant pathogens. In this study, mutagenesis of a defined region within the VipA protein was used to identify residues important for VipB binding in V. cholerae O1 strain A1552.

Results

A dramatically diminished interaction was shown to correlate with a decrease in VipB stability and a loss of hemolysin co-regulated protein (Hcp) secretion and rendered the bacterium unable to compete with Escherichia coli in a competition assay.

Conclusions

This confirms the biological relevance of the VipA-VipB interaction, which is essential for the T6SS activity of many important human pathogens.

SUBMITTER: Broms JE

PROVIDER: S-EPMC3656785 | biostudies-literature | 2013 May

REPOSITORIES: biostudies-literature

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A functional VipA-VipB interaction is required for the type VI secretion system activity of Vibrio cholerae O1 strain A1552.

Bröms Jeanette E JE Ishikawa Takahiko T Wai Sun N SN Sjöstedt Anders A

BMC microbiology 20130503

<h4>Background</h4>Many Gram-negative bacteria rely on a type VI secretion system (T6SS) to infect eukaryotic cells or to compete against other microbes. Common to these systems is the presence of two conserved proteins, in Vibrio cholerae denoted VipA and VipB, which have been shown to interact in many clinically relevant pathogens. In this study, mutagenesis of a defined region within the VipA protein was used to identify residues important for VipB binding in V. cholerae O1 strain A1552.<h4>R ...[more]

PMID: 23642157

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