Department of Bioengineering, Rice University, 6100 Main St., Houston, 77005, TX, USA.
Department of Biosciences, Rice University, 6100 Main St., Houston, 77005, TX, USA.
Nat Commun. 2018 Apr 12;9(1):1433. doi: 10.1038/s41467-018-03929-y.
Two-component systems (TCSs) are the largest family of multi-step signal transduction pathways in biology, and a major source of sensors for biotechnology. However, the input concentrations to which biosensors respond are often mismatched with application requirements. Here, we utilize a mathematical model to show that TCS detection thresholds increase with the phosphatase activity of the sensor histidine kinase. We experimentally validate this result in engineered Bacillus subtilis nitrate and E. coli aspartate TCS sensors by tuning their detection threshold up to two orders of magnitude. We go on to apply our TCS tuning method to recently described tetrathionate and thiosulfate sensors by mutating a widely conserved residue previously shown to impact phosphatase activity. Finally, we apply TCS tuning to engineer B. subtilis to sense and report a wide range of fertilizer concentrations in soil. This work will enable the engineering of tailor-made biosensors for diverse synthetic biology applications.
双组分系统（TCSs）是生物学中多步骤信号转导途径的最大家族，也是生物技术传感器的主要来源。然而，生物传感器响应的输入浓度通常与应用要求不匹配。在这里，我们利用数学模型表明，TCS 检测阈值随传感器组氨酸激酶的磷酸酶活性增加而增加。我们通过调整工程枯草芽孢杆菌硝酸盐和大肠杆菌天冬氨酸 TCS 传感器的检测阈值，实验验证了这一结果，最高可达两个数量级。我们接着通过突变一个先前被证明影响磷酸酶活性的广泛保守残基，将我们的 TCS 调节方法应用于最近描述的连四硫酸盐和硫代硫酸盐传感器。最后，我们应用 TCS 调节工程枯草芽孢杆菌来感知和报告土壤中广泛的肥料浓度。这项工作将使针对各种合成生物学应用定制生物传感器的工程成为可能。
