Fig. 1: Building blocks used in this study to construct a designer tri-zinc enzyme.

a Schematic and b crystal structures of the synthetic trinuclear zinc complex (CCDC 931956)⁴³, and c crystal structure of human MIF (PDB code: 1MIF), which is also known as a moonlighting protein, displaying the active sites for its multiple functionalities. The structural illustrations in this report were generated using CueMol2 (http://www.cuemol.org/en/). In (b), zinc, carbon, oxygen, and nitrogen atoms are shown in dark purple, cyan, red, and blue, respectively. c depicts oxygen in red and nitrogen in blue, while the carbon atoms are color-coded according to their functionality. Residues with carbon atoms in orange and yellow correspond to the CD74 binding site. Residues with the carbon atoms in cyan indicate the nuclease-active site, whereas those with carbon atoms in pink represent the tautomerase-active site.