Fig. 6.

A superfamily (CATH 3.20.20.150) containing enzymes with different EC numbers and different nuclearity of the metal site. The aligned protein structures (top), the aligned metal site structures (middle, metal ions are depicted as red spheres), and the structure-based alignment of the metal-binding ligands (bottom, different colors indicate the ligands of individual metal ions) are shown. The EC number of each enzyme is reported above the structure. (For interpretation of the references to color in this figure legend, the reader is referred to the web version of this article.)