Related Experiment Video
Updated: Jun 12, 2026
06:21
An Ecdysone Receptor-based Singular Gene Switch for Deliberate Expression of Transgene with Robustness, Reversibility, and Negligible Leakiness
Published on: May 7, 2018
Cascading recombinase memory switch for programmable and stable gene expression in Pseudomonas putida.
Javier M Hernández-Sancho1, Daniel C Volke1, Pablo I Nikel1
1BRIGHT, Technical University of Denmark, 2800 Kongens Lyngby, Denmark.
Nucleic Acids Research
|June 10, 2026
Summary
We developed a genetic toggle switch for reliable gene control in Pseudomonas putida. This system enables stable microbial phenotypes and programmable bioprocesses using genetic memory.
Area of Science:
- Synthetic Biology
- Microbial Engineering
- Biotechnology
Background:
- Genetic circuits often fail in non-model bacteria, hindering industrial applications.
- Developing robust gene regulation systems for industrial microbes like Pseudomonas putida is crucial.
Purpose of the Study:
- Engineer a stable, programmable genetic toggle switch for Pseudomonas putida.
- Create a genetic memory element to control bioprocess-relevant phenotypes.
Main Methods:
- Designed an integrase-based cascading toggle switch using Bxb1 serine integrase and a T7 RNA polymerase system.
- Optimized gene expression for tight OFF states and strong induction.
- Integrated the switch into a 2-fluoro-cis,cis-muconic acid production strain to control biofilm formation.
Main Results:
- Achieved consistent and programmable gene expression with stable phenotypes after inducer removal.
- Demonstrated efficient switching and genetic memory.
- Successfully engineered switch-mediated catalytic biofilms for continuous chemical production.
Conclusions:
- The developed toggle switch expands the synthetic biology toolbox for Pseudomonas.
- This system links heritable genetic memory to stable microbial phenotypes for bioprocesses.
- Enables robust control of microbial functions in industrially relevant organisms.
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