The secondary structures and surface hydrophobicity of 2PBJ and 1CYO. The heme is represented as spheres. The color of the surfaces represents the level of hydrophobicity. The blue, white, and brown colors represent low, mediate, and high hydrophobicity, respectively. (a) The structures of 2PBJ where a CP motif is located near the heme for the interaction with the heme. (b) Surface hydrophobicity of 2PBJ. The heme is represented as yellow sticks. (c) The structures of 1CYO. (d) Surface hydrophobicity of 1CYO. Protein structures are drawn using Discovery studio 4.0.