Fig. 1. (A) Chemical structure of malachite green and various degradation approaches; (B) rational design of artificial enzyme in the protein matrix of myoglobin (Mb) by introducing a distal histidine and creating a channel to the heme pocket. The X-ray structures of WT Mb (PDB code 1JP6 ³³), F43H Mb (PDB code 4PQC³⁰), and F43H/H64A Mb (PDB code 5HLQ³¹) were shown for the heme active site, respectively.