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Updated: May 14, 2026
07:10
A Fluorescence-based Method to Study Bacterial Gene Regulation in Infected Tissues
Published on: February 19, 2019
Autonomous bacterial localization and gene expression based on nearby cell receptor density
Hsuan-Chen Wu1, Chen-Yu Tsao, David N Quan
1Fischell Department of Bioengineering, University of Maryland, College Park, MD, USA.
Molecular Systems Biology
|January 24, 2013
Summary
Engineered bacteria can sense and respond to surface features, enabling targeted responses. This synthetic biology approach directs bacteria to cancer cells, initiating drug delivery based on receptor density.
Area of Science:
- Synthetic Biology
- Microbial Engineering
- Biotechnology
Background:
- Bacteria can be engineered for specific functions.
- Quorum sensing is a cell-to-cell communication mechanism used by bacteria.
- Targeted drug delivery remains a challenge in cancer therapy.
Purpose of the Study:
- To engineer Escherichia coli for programmed motility, sensing, and actuation based on surface feature density.
- To develop a novel controller for targeted drug delivery using engineered bacteria.
- To demonstrate bacteria's ability to detect and respond to specific cellular markers.
Main Methods:
- Genetic modification of Escherichia coli for programmed responses.
- Rewiring of the bacterial quorum sensing autoinducer-2 (AI-2) signaling pathway.
- Utilizing epidermal growth factor receptor (EGFR) density as a trigger for gene expression.
Main Results:
- Engineered E. coli demonstrated density-dependent motility and gene expression.
- Bacteria were successfully directed to squamous cancer cells (SCCHN).
- Reporter synthesis (drug surrogate) was initiated based on EGFR density thresholds.
Conclusions:
- Engineered bacteria can act as a novel controller for targeted drug delivery.
- Area-based switching in synthetic biology enables precise, density-dependent responses.
- This platform has potential applications beyond cancer therapy, showcasing a new paradigm in microbial engineering.
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