Whole-cell and cell-free biosensor-driven metabolic engineering

Metabolic engineering employs microbial cell factories to produce high-value products from low-cost feedstocks. Designing, optimizing, and evaluating biosynthetic pathways in microbial cell factories is essential, yet these processes remain time- and labor-intensive. Biosensors help metabolic engineers address this challenge by converting target metabolite concentrations into observable outputs, enabling efficient assessment of microbial production. Whole-cell biosensors, which operate within living microorganisms, and cell-free biosensors, which function independently of cell growth using transcription-translation machinery, have contributed to microbial biosynthesis optimization through distinct approaches. This review summarizes recent advances in biosensor-driven metabolic engineering facilitated by whole-cell and cell-free biosensors.