Biological Sentinel: An Efficient Engineered Bacterial System for Monitoring and Tracing Regulated Hazardous Chemicals

Monitoring
and tracing of regulated hazardous chemicals is a public
security issue of global concern. However, accurately recording historical
exposure remains challenging. Here, we designed a Biological Sentinel System (BOSS) for in situ and long-term monitoring of
hazardous chemical exposure using a chemical-induced base-editing
system that activates antibiotic resistance screening, producing an
obvious colorimetric signal. Exposure events can be written into an
inheritable genomic DNA sequence, which can be read using gene sequencing.
As a proof of concept, we demonstrated the accurate detection of cocaine
and 2,4-dinitrotoluene using BOSS under simulated application scenarios.
In addition, we integrated alternative biosensors to illustrate the
modularity and extensibility of this monitoring platform. This work
provides a promising paradigm for developing engineered microorganisms
as an alternative to electronic monitors for regulated hazardous chemicals.