Linker Engineering in the Context of Synthetic Protein Switches and Sensors

• Published in: Trends in biotechnology (Regular ed.) Vol. 39; no. 7; pp. 731 - 744
• Main Authors: Gräwe, Alexander, Stein, Viktor
• Format: Journal Article
• Language: English
• Published: Oxford Elsevier Ltd 01.07.2021; Elsevier Limited
• Subjects: Actuators; Amino acids; biosensors; Engineering; fluorescent protein sensors; linker engineering; Polypeptides; protein engineering; Proteins; Response functions; Sensors; Switches; synthetic biology; synthetic protein Switches; synthetic biology; protein engineering; synthetic protein Switches; biosensors; linker engineering; fluorescent protein sensors
• ISSN: 0167-7799; 1879-3096
• DOI: 10.1016/j.tibtech.2020.11.007

Linkers play critical roles in the construction of synthetic protein switches and sensors as they functionally couple a receptor with an actuator. With an increasing number of molecular toolboxes and experimental strategies becoming available that can be applied to engineer protein switches and sensors with tailored response functions, optimising the connecting linkers remains an idiosyncratic and empiric process. This review aims to provide an in-depth analysis of linker motifs, the biophysical properties they confer, and how they impact the performance of synthetic protein switches and sensors while identifying trends, mechanisms, and strategies that underlie the most potent switches and sensors. Artificially engineered protein switches and sensors with tailored response functions are finding increasing applications in biotechnology, biomedicine, and basic research.Tailored protein switches and sensors can be readily engineered through recombination of a receptor protein with different types of actuators.Linkers connecting the receptor protein with the actuator are critical and highly plastic in relaying conformational transitions following different input signals.Different types of protein switches and sensors impose different functional requirements on the identity of linkers.Nonconventional linkers with increasing degrees of chemical functionalisation and secondary structures are yielding increasingly potent protein switches and sensors that frequently outperform conventional Gly-rich linkers.