Some prokaryotes, including Escherichia coli and Pseudomonas putida naturally produce enzymes capable of detecting toxic aromatic molecules and regulating the transcription of corresponding catabolic genes. However, these naturally existing biosensors are limited in terms of their detection range, expression leakage, and induction ratio.
This year our team designed a series of aromatic sensors and combined them with related enzymes from their original catabolic pathways to increase the number of molecules the sensors can detect. In order to semi-quantitatively measure the concentrations of these compounds, we constructed a biological band-pass circuit, enabling our sensors to detect the concentrations of target compounds within a certain range. Our system is a fast and easy way of detecting aromatic pollution, and another step forward in ensuring water safety.