Artificial heme-enzymes for the construction of functional nanomaterials

Recent advances in the field of enzyme design and engineering have significantly expanded the chemist’s toolbox, providing a collection of catalysts tailored for specific applications.[1] In this context, we have developed a class of miniaturized heme-enzymes, named Mimochromes (MCs), inspired by the active site of peroxidases.[2] Owing to their reduced size (~3 kDa), MCs lie at the interface between metalloproteins and small-molecule complexes, combining the exceptional catalytic performances of natural enzymes with the promiscuity of synthetic catalysts. Among them, we have identified MC6*a as the lead compound and demonstrated its ability to host and modulate the reactivity of different metal ions in the frame of oxidation[3-5] and energy-related[6] catalysis. Within the efforts of exploiting MCs for practical uses in catalysis and sensor technology, we have analysed their behaviour upon immobilization onto different surfaces.[7] Our most recent studies show that FeMC6*a can be efficiently immobilized onto differently shaped gold-based nanomaterials, retaining its structural and catalytic properties. With the aim of developing innovative, sustainable and cost-effective functional nanomaterials, we are currently assembling completely peptide-based nanostructures. To this end, we have selected and modified amyloid forming peptide sequences to achieve functionalized fibrils displaying our miniaturized heme-enzymes. Structural and catalytic studies demonstrate the feasibility of this approach, opening the chance to a plethora of applications in the field of biosensing and catalysis.