A Photoregulated Peptidase Mimic

Proteases and peptidases play crucial roles in numerous biological processes. These enzymes bind to protein substrates and hydrolyze peptide bonds, resulting in the cleavage of proteins and peptides into smaller fragments. This study reports on a small-molecule light activated peptidase (SLAP) enzyme mimic featuring a glucose-linked photoswitch-imidazole triad, where peptidase activity can be controlled by light by tuning the distance between the basic imidazole residue, the reaction center, and the sugar moiety, that provides a binding site for the substrate and also takes a role in stabilizing the transition state. The cis isomer exhibited a ∼300-fold increase in catalytic activity compared to its inactive trans counterpart with a model amide-substrate. Catalytic hydrolysis was studied with small molecules, FRET-based substrates, and large cellular proteins. The light-controlled peptidase activity opens new possibilities for protein degradation in biological systems.