Design and engineering of genetically encoded protein biosensors for small molecules

Genetically encoded protein biosensors controlled by small organic molecules are valuable tools for many biotechnology applications, including control of cellular decisions in living cells. Here, we review recent advances in protein biosensor design and engineering for binding to novel ligands. We categorize sensor architecture as either integrated or portable, where portable biosensors uncouple molecular recognition from signal transduction. Proposed advances to improve portable biosensor development include standardizing a limited set of protein scaffolds, and automating ligand-compatibility screening and ligand–protein-interface design. [Display omitted] •Ligand-responsive biosensors are integral to cellular-control applications.•Integrated biosensors connect ligand recognition to a single output signal.•Portable biosensors consist of interchangeable signaling components.•Standardized protein scaffolds can enable automated ligand-compatibility screening.•Novel standardized scaffolds can expand the chemical space recognized by biosensors.