Fig. 2. Active site residues (grey) and diazepinone riboside (green) of hCDA (1MQ0) overlaid with the active site of A3A (5KEG) (cyan). Tyr 130 (cyan) of A3A is on the same place as Phe 137 (orange) of hCDA interacting with diazepinone; zinc²⁺ atoms are shown as spheres. Structures were overlaid in pymol. The CDA tetramer is shown in ESI Fig. S2.†.