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Vibrio parahaemolyticus T6SS2 effector repertoires
Daniel Tchelet1, Kinga Keppel1, Eran Bosis2
1Department of Clinical Microbiology and Immunology, Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel.
Gut Microbes
|February 21, 2023
Summary
Marine bacteria Vibrio parahaemolyticus possess a type VI secretion system (T6SS2) crucial for their life cycle. This study identifies novel antibacterial effectors, revealing both core and accessory components of the T6SS2 secretome.
Area of Science:
- Microbiology
- Bacterial Pathogenesis
- Molecular Biology
Background:
- The marine bacterium *Vibrio parahaemolyticus* is an emerging pathogen.
- All strains harbor a type VI secretion system (T6SS) designated T6SS2, implying its significance in the bacterial life cycle.
- T6SS2's role in interbacterial competition is known, but its effector repertoire remains uncharacterized.
Purpose of the Study:
- To investigate the T6SS2 secretome of *V. parahaemolyticus*.
- To identify and characterize the antibacterial effectors secreted by T6SS2.
- To elucidate the composition of the T6SS2 effector arsenal.
Main Methods:
- Proteomics was employed to analyze the T6SS2 secretome.
- Two *V. parahaemolyticus* strains were utilized for secretome analysis.
- Effector identification involved analyzing proteins secreted by T6SS2.
Main Results:
- Several antibacterial effectors were identified, with some encoded outside the main T6SS2 gene cluster.
- Two conserved T6SS2-secreted proteins were revealed, forming the core secretome.
- Accessory effectors, present in subsets of strains, were also identified.
- A conserved Rhs repeat-containing effector was found to be essential for T6SS2 activity, acting as a quality control checkpoint.
Conclusions:
- The study reveals the effector repertoires of a conserved T6SS, T6SS2.
- Identified effectors include both conserved core components and strain-specific accessory components.
- The findings uncover novel effectors with previously unknown activities and T6SS associations, including a key Rhs effector for T6SS2 function.
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