Multiple sequence alignment of NACHT domains of NLRPs, NOD1, NOD2 and Nlrc4; the residues interacting with ATP are displayed in bold fonts.

The critical ATP-binding residues (proved experimentally), presented in red-bold font; the residues found within 5-6Å of ATP (adopted from atomic/residual distance calculation; Fig 4) are visualized in black fonts. The sequence motifs crucial for ATP binding are boxed in different colors (Walker A: blue; Walker B: salmon; Sensor 1: orange; GFxxxxRxxYF motif: light gray; PhhCW motif: green; WH-His: purple). The key ATP-coordinating residues are highlighted in yellow boxes and are marked in inverted triangle.