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Updated: Oct 27, 2025
21:08
Engineering Cell-permeable Protein
Published on: December 28, 2009
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Engineered Type Six Secretion Systems Deliver Active Exogenous Effectors and Cre Recombinase
Steven J Hersch1, Linh Lam1, Tao G Dong1,2
1Department of Ecosystem and Public Health, University of Calgarygrid.22072.35, Calgary, Alberta, Canada.
Mbio
|July 20, 2021
Summary
Researchers engineered the bacterial type VI secretion system (T6SS) to deliver Cre recombinase protein for genetic editing, avoiding DNA integration risks. This T6SS protein delivery system also successfully killed Pseudomonas aeruginosa, offering a new antimicrobial strategy.
Area of Science:
- Microbiology and Biotechnology
- Molecular Biology
- Bacterial Pathogenesis
Background:
- Genetic editing technologies face challenges with DNA delivery, including aberrant integration and off-target effects.
- The bacterial type VI secretion system (T6SS) is a versatile protein delivery machine capable of targeting various cells.
Purpose of the Study:
- To develop a novel protein delivery mechanism using T6SS for genetic editing applications.
- To demonstrate the efficacy of T6SS-mediated delivery of Cre recombinase for bacterial genetic modification.
- To explore the potential of T6SS for delivering antimicrobial effectors against resistant pathogens.
Main Methods:
- Engineering of T6SS fusion proteins using Aeromonas dhakensis and attenuated Vibrio cholerae donor strains.
- Utilizing a gain-of-function cassette to detect Cre recombination in recipient cells.
- Employing a truncated PAAR2 tag from V. cholerae for efficient protein delivery.
Main Results:
- Successful delivery of active Cre recombinase protein into recipient cells via engineered T6SS.
- Demonstrated efficient protein transfer using a small, 118-amino-acid V. cholerae PAAR2-derived tag.
- Engineered T6SS delivered TseC effector to kill Pseudomonas aeruginosa, which is naturally resistant to V. cholerae effectors.
Conclusions:
- T6SS-mediated protein delivery offers a DNA-free alternative for genetic editing, bypassing risks of integration and overexpression.
- The engineered T6SS system shows promise as a next-generation antimicrobial agent against drug-resistant pathogens.
- This adaptable protein delivery platform has broad applications in studying T6SS effectors, microbiome manipulation, and therapeutic development.
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