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Bacillus subtilis GntR regulation modified to devise artificial transient induction systems.
Parastoo Majidian1, Junko Kuse, Kosei Tanaka
1Department of Agrobioscience, Kobe University.
The Journal of General and Applied Microbiology
|November 11, 2016
Summary
Researchers engineered Bacillus subtilis for transient gene induction by modifying GntR regulation. This system allows controlled gene expression, enabling flexible metabolic engineering applications with temporary gene activation as needed.
Area of Science:
- Microbiology
- Metabolic Engineering
- Synthetic Biology
Background:
- GntR regulates gluconate catabolism in Bacillus subtilis.
- Carbon catabolite repression by CcpA/P-ser-HPr affects gnt operon expression via cre sites.
- Existing systems lack precise temporal control over gene expression.
Purpose of the Study:
- To develop a transient gene induction system in Bacillus subtilis.
- To overcome carbon catabolite repression affecting GntR-regulated genes.
- To enable flexible and temporary gene expression for metabolic engineering.
Main Methods:
- Modified GntR regulation and initiated expression of gntKPZ independently.
- Mutated carbon catabolite repression (cre) sites within the gnt promoter and gntR coding region.
- Utilized a lacZ reporter gene under GntR control to monitor induction.
Main Results:
- Achieved constitutive degradation of gluconate by independent gntKPZ expression.
- Abolished carbon catabolite repression by mutating cre sites.
- Demonstrated transient lacZ induction upon gluconate addition, even with glucose present.
- Showcased successful gene expression shutdown as gluconate was consumed.
Conclusions:
- Modified GntR regulation provides a robust system for artificial transient gene induction.
- The developed system allows for precise temporal control of gene expression.
- This offers a flexible platform for designing advanced metabolic engineering strategies.
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