A Whole-Cell Biosensor for Point-of-Care Detection of Waterborne Bacterial Pathogens

Abstract

Water contamination by pathogenic bacteria is a major public health concern globally. Monitoring bacterial contamination in water is critically important to protect human health, but this remains a critical challenge. Engineered whole-cell biosensors created through synthetic biology hold great promise for rapid and cost-effective detection of waterborne pathogens. In this study, we created a novel whole-cell biosensor to detect water contamination by Pseudomonas aeruginosa and Burkholderia pseudomallei, which are two critical bacterial pathogens and are recognized as common causative agents for waterborne diseases. The biosensor detects the target bacterial pathogens by responding to the relevant quorum sensing signal molecules. Particularly, this study constructed and characterized the biosensor on the basis of the QscR quorum sensing signal system for the first time. We first designed and constructed a QscR on the basis of the sensing module in the E. coli host cell and integrated the QscR sensing module with a reporting module that expressed an enhanced green fluorescent protein (EGFP). The results demonstrated that the biosensor had high sensitivity in response to the quorum sensing signals of the target bacterial pathogens. We further engineered a biosensor that expressed a red pigment lycopene in the reporting module to produce a visible signal readout for the pathogen detection. Additionally, we investigated the feasibility of a paper-based assay by immobilizing the lycopene-based whole-cell biosensor on paper with the aim to build a prototype for developing portable detection devices. The biosensor would provide a simple and inexpensive alternative for timely and point-of-care detection of water contamination and protect human health.

Transcription Factor-Based Biosensors for Detecting Pathogens

“…In Table 2, the quorum-sensing molecules, bacterial species, the responding genetic systems, and the corresponding TF-based biosensors are summarized. Recently, many TF-biosensors have been developed for detecting pathogenic microorganisms by targeting quorum sensing (QS) molecules [76,87,88]. Quorum sensing is the ability to detect and respond to cell population density by gene regulation [89,90].…”

“…Recently, many TF-biosensors have been developed for detecting pathogenic microorganisms by targeting quorum sensing (QS) molecules [ 76 , 87 , 88 ]. Quorum sensing is the ability to detect and respond to cell population density by gene regulation [ 89 , 90 ].…”

Synthetic Biology Tools for Engineering Microbial Cells to Fight Superbugs

“…Recently, Wu et al created a novel whole-cell biosensor to detect bacterial pathogens ( P. aeruginosa and Burkholderia pseudomallei ) by responding to the relevant QS signal molecules. Results showed that engineered whole-cell biosensors provide rapid and cost-effective detection of waterborne pathogens ( Wu et al, 2021 ).…”

Inkjet Printing: A Viable Technology for Biosensor Fabrication

“…Moreover, the ad hoc detection and monitoring of bacterial infections [21,22] can provide convenience for the patients and improved healthcare in hospitals. Testing food and water contamination is another area where biosensors excel in terms of cost effectiveness and as rapid assay tools [23][24][25]. In short, biosensors provide portability and the rapid, low-cost, and early diagnosis of pathologies such as cardiac or neurodegenerative diseases, infectious diseases, cancer, fatal viruses, bacterial infections, pregnancy tests, and more, anywhere and anytime.…”