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Updated: Feb 16, 2026
An Anaerobic Biosensor Assay for the Detection of Mercury and Cadmium
Published on: December 17, 2018
Engineering highly sensitive whole-cell mercury biosensors based on positive feedback loops from quorum-sensing
Sheng Cai1, Yifei Shen, Yan Zou
1State Key Laboratory of Coordination Chemistry, Institute of Chemistry and BioMedical Sciences, School of Chemistry and Chemical Engineering, Collaborative Innovation Center of Chemistry for Life Sciences, Nanjing University, Nanjing 210093, China. weiwei@nju.edu.cn jingzhao@nju.edu.cn.
Abstract:
Mercury contamination represents a global threat. A simple, sensitive, and rapid means of detecting trace mercury is urgently needed. Herein, we have developed a series of mercury biosensors by combining quorum sensing-based positive feedback systems with a mercury-specific operon, merR. Our results have demonstrated that the sensitivity and fluorescence intensity of the engineered E. coli cells were greatly improved thanks to the positive feedback system. In addition, by fitting the fluorescence signals to the classic Hill equation, we discovered that the responses of the engineered E. coli cells were close to ultrasensitive curves. Our work highlights quorum-sensing systems as a powerful tool in biosensor designs.
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