Figure 1: The three-dimensional structures of Escherichia coli adenylate kinase in the open (a) and closed (b) conformations. The crystal structures 4ake.pdb and 1ake.pdb are selected as the open and closed state of ADK, respectively. NMP (residues 30–67), CORE (residues 1–29, 68–117, and 161–214), and LID (residues 118–167) domains are colored in red, yellow, and blue, respectively.