Enhancing DNT Detection by a Bacterial Bioreporter: Directed Evolution of the Transcriptional Activator YhaJ
Abstract
Detection of buried landmines is a dangerous and complicated task that consumes large financial resources and poses significant risks to the personnel involved. A potential alternative to conventional detection methodologies is the use of microbial bioreporters, capable of emitting an optical signal upon exposure to explosives, thus revealing to a remote detector the location of buried explosive devices. We have previously reported the design, construction, and optimization of an Escherichia coli-based bioreporter for the detection of 2,4,6-trinitrotoluene (TNT) and its accompanying impurity 2,4-dinitrotoluene (DNT). Here we describe the further enhancement of this bioreporter by the directed evolution of YhaJ, the transcriptional activator of the yqjF gene promoter, the sensing element of the bioreporter’s molecular circuit. This process resulted in a 37-fold reduction of the detection threshold, as well as significant enhancements to signal intensity and response time, rendering this sensor strain more suitable for detecting the minute concentrations of DNT in the soil above buried landmines. The capability of this enhanced bioreporter to detect DNT buried in sand is demonstrated.
Document Details
- Document Type
- Pub Defense Publication
- Publication Date
- Feb 14, 2022
- Source ID
- 10.3389/fbioe.2022.821835
Entities
People
- Aharon J. Agranat
- Azriel Gold
- Benjamin Shemer
- Etai Shpigel
- Shilat Simanowitz
- Shimshon Belkin
- Tal Elad
- Yosef Mizrachi
- Yossef Kabessa
Organizations
- Defense Advanced Research Projects Agency