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Updated: Sep 28, 2025
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Preparation and Application of a New Bacterial Biosensor for the Presumptive Detection of Gunshot Residue
Published on: May 9, 2019
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Introduction of quorum sensing elements into bacterial bioreporter circuits enhances explosives' detection
Etai Shpigel1, Shiri Nathansohn1, Anat Glozman1
1Department of Plant and Environmental Sciences The Alexander Silberman Institute of Life Sciences The Hebrew University of Jerusalem Jerusalem Israel.
Engineering in Life Sciences
|April 6, 2022
Summary
This study engineered a novel microbial bioreporter for detecting 2,4-dinitrotoluene (DNT), a key explosive chemical. The enhanced biosensor significantly improves standoff detection capabilities for buried landmines.
Area of Science:
- Microbiology
- Biotechnology
- Chemical Sensing
Background:
- Landmine detection remains a critical challenge, necessitating advanced standoff sensing technologies.
- Microbial bioreporters offer a sensitive platform for detecting trace amounts of explosive chemicals like 2,4-dinitrotoluene (DNT).
- Previous DNT sensor strains relied on direct promoter-reporting element fusion.
Purpose of the Study:
- To develop a novel microbial bioreporter for enhanced standoff detection of 2,4-dinitrotoluene (DNT).
- To engineer a more sensitive and robust biosensor by utilizing a quorum-sensing system and genetic modifications.
- To improve upon existing DNT detection methods for landmine applications.
Main Methods:
- Engineered *Escherichia coli* to activate quorum-sensing genes (*luxI* and *luxR*) in response to DNT.
- Utilized N-acyl homoserine lactone (AHL) signaling to activate bioluminescence reporter genes.
- Enhanced sensor performance through promoter manipulation (*azoR*, *yqjF*), luminescence gene replacement (*A. fischeri luxCDABEG*), and host strain mutations (*eutE*, *ygdD*).
Main Results:
- The developed bioreporter exhibited a dose-dependent luminescent signal in the presence of DNT.
- Genetic modifications and strain engineering led to a significant increase in DNT detection sensitivity.
- The final bioreporter demonstrated over 340-fold higher sensitivity compared to the original construct.
Conclusions:
- The novel quorum-sensing based microbial bioreporter represents a significant advancement in DNT detection.
- This engineered biosensor shows great promise for improving standoff detection of buried landmines.
- Further optimization could lead to practical field applications for explosive detection.
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