Engineering Allosteric Transcription Factor-Based Biosensors: Advances and Prospects for Modern Food Contaminant Monitoring

Allosteric transcription factor (aTF)-based in vitro biosensors constitute a class of detection tools formed by the functional coupling of the ligand-binding domain of aTFs with a reporter system. Owing to advantages such as high specificity and sensitivity, these biosensors have emerged as a research hotspot in the field of modern food contaminant monitoring. Our work centers on the core aspect of engineering design and systematically elaborates on the modular design strategies for aTF-based in vitro biosensors, with a focus on the design principles of the molecular recognition system, signal amplification strategies, signal output systems, and sensing systems. Furthermore, the article summarizes the advances in the application of aTF biosensors for detecting various typical food contaminants and analyzes their performance advantages. Finally, in light of existing technical limitations, it prospectively discusses future directions for enhancing specificity, improving stability, and promoting commercial applications, aiming to provide a theoretical reference and application guidance for transitioning this technology from laboratory platforms to on-site real-time monitoring.