A rainbow of rapid peptide superglues for engineering biological teams

Biological function typically depends on proteins working together in teams. Routes for programming protein assembly should be specific and reliable in the context of many different proteins and cellular environments. Our group has generated a peptide called SpyTag and a protein called SpyCatcher (named after the bacterium S. pyogenes from which these parts were engineered). SpyTag/SpyCatcher technology has proven to be a powerful tool for bringing two proteins together simply, specifically and irreversibly. SpyTag technology has enabled diverse applications including in biomaterials, catalysis, cell therapy, structural biology and vaccines. SpyTag/SpyCatcher has been employed in bacteria, plants, mice, worms, flies, a range of livestock animals, and even in human clinical trials.
Linking building-blocks irreversibly brings resilience over time and enhances the ability to monitor interactions in cells. We and others have now generated a set of Tag/Catcher pairs, harnessing the same idea of ligation through spontaneous covalent bond formation. However, these tools have low reaction speed, low ability as fusion partners and it is unknown whether the pairs are mutually specific and applicable in diverse cellular contexts. Here we will engineer a panel of Tag/Catcher pairs where each Tag or Catcher only reacts with its designated partner, ignoring other Tag/Catchers and other components of cells. This Tag/Catcher panel will provide a central underlying resource for the engineering of biology. This work will also establish fundamental insights into the computational design of split proteins for rapid reaction and cellular compatibility.
Objective 1: Benchmarking the performance of the existing Tag/Catcher rainbow
First we will quantify and compare key criteria for the large set of existing Tag/Catcher pairs, including reaction efficiency and selectivity. This objective will establish which pairs are best suited to take forwards to engineer for efficient building of...