School of Chemistry, Northeast Normal University, Changchun, Jilin, China.
State Key Laboratory of Electroanalytical Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun, Jilin, China.
Commun Biol. 2024 Oct 29;7(1):1407. doi: 10.1038/s42003-024-07112-6.
Recent advancements in bacterial two-component systems (TCS) have spurred research into TCS-based biosensors, notably for their signal amplification and broad input responsiveness. The CusRS system in Escherichia coli (E. coli), comprising cusS and cusR genes, is a copper-sensing module in E. coli. However, due to insufficient sensing performance, CusRS-based biosensors often cannot meet practical requirements. To address this issue, we made improvements and innovation from several aspects. CusR and CusS expression were adjusted to enhance the Cu(II) biosensor's performance. A copy-number inducible plasmid was used for signal amplification, while removing copper detox genes cueO and cusCFBA improved sensitivity and lowered detection limits. Ultimately, in the optimized biosensor of Cu26, the fold-change (I/I) increased from 1.5-fold to 18-fold at 1 μM, rising to 100-fold after optimizing the cell culture procedure. The biosensor's high fluorescence enabled rapid, instrument-free detection and an improved analysis strategy reduced the detection limit to 0.01 μM, surpassing traditional methods.
近年来，细菌双组分系统（TCS）的研究取得了进展，这促使人们研究基于 TCS 的生物传感器，特别是因为它们具有信号放大和广泛的输入响应能力。大肠杆菌（E. coli）中的 CusRS 系统由 cusS 和 cusR 基因组成，是大肠杆菌中的一种铜感应模块。然而，由于感应性能不足，基于 CusRS 的生物传感器通常无法满足实际需求。为了解决这个问题，我们从几个方面进行了改进和创新。调整了 CusR 和 CusS 的表达，以增强 Cu(II)生物传感器的性能。使用拷贝数诱导型质粒进行信号放大，同时去除铜解毒基因 cueO 和 cusCFBA 提高了灵敏度并降低了检测限。最终，在优化后的 Cu26 生物传感器中，在 1 μM 时，荧光强度比从 1.5 倍增加到 18 倍，在优化细胞培养程序后增加到 100 倍。该生物传感器具有高荧光，可实现快速、无仪器检测，改进的分析策略将检测限降低至 0.01 μM，超过了传统方法。
