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.

中文翻译：

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根据群体感应系统的正反馈回路设计高度敏感的全细胞汞生物传感器†

汞污染是全球性威胁。迫切需要一种简单，灵敏，快速的痕量汞检测方法。本文中，我们通过将基于群体感应的正反馈系统与特定于汞的操纵子merR相结合，开发了一系列汞生物传感器。我们的结果表明，借助正反馈系统，工程大肠杆菌细胞的灵敏度和荧光强度得到了极大的提高。此外，通过将荧光信号拟合为经典的希尔方程，我们发现工程化大肠杆菌细胞的响应接近超灵敏曲线。我们的工作着重说明群体感应系统是生物传感器设计中的强大工具。