Box 2 Figure.
Stucture of the archetypal processive protease. Side view of the soluble domain structure of the hexameric FtsH protease from a thermophilic bacterium Thermus thermophiles is shown as a representative structure of the processive protease. Its characteristic AAA+ unfoldase chaperone and protease domains are indicated. The image of the FtsH structure (PDB ID: 4EIW) was obtained from the Protein Data Bank of Japan (PDBj).