A functional mimic of natural peroxidases: synthesis and catalytic activity of a non-heme iron/peptide hydroperoxide complex

Site-selective attachment of unprotected peptides to a non-heme iron complex is achieved by displacing two halides on the catalyst by peptide caesium thiolates. This coupling approach should be compatible with any peptide sequence provided there is only a single reduced cysteine. The oxidation activity with hydrogen peroxide of the dipeptide–catalyst complex in water is retained, and shows similarities with oxidation mechanisms observed for natural oxidizing enzymes. The results pave the way for the future design of peroxidase mimics where the activity of the catalyst will be modulated by a designed protein matrix.