Design, synthesis and peroxidase-like activity of 3α-helix proteins covalently bound to heme

As a model of artificial peroxidase, de novo designed three-α-helix proteins, 3α-H9 and 3α-H12, covalently bound to Fe(III)-mesoporphyrin IX were synthesized and examined for a peroxidase-like activity. The activity was regulated according to the positions of His residues in the proteins, and the His residues played a role in an acid–base catalytic function.