Fish and Clips: A Convenient Strategy to Identify Tyrosinase Substrates with Rapid Activation Behavior for Materials Science Applications

Peptides with suitable substrate properties for a specific tyrosinase are selected by combinatorial means from a one-bead-one-compound (OBOC) peptide library. The identified sequences exhibit tyrosine residues that are rapidly oxidized to 3,4-dihydroxyphenylalanine (Dopa), making the peptides interesting for enzyme-activated adhesives. The selection process of peptides involves tyrosinase oxidation of tyrosine-bearing sequences on a solid support, yielding dopaquinone residues (fish from the sequence pool), to which thiol-functional fluorescent probes attach by Michael-reaction (clip to mark). Labeled supports are isolated and sequence readout is feasible by MALDI-TOF-MS/MS to reveal peptides, while activation kinetics as well as enzyme-activated coating behavior are verifying the proper selection.