AAA Proteins - AAAs Are Often Hexamers

AAAs Are Often Hexamers

The physiologically active form of these enzymes is often a homo-hexamer. The hexameric enzymes have an overall shape that resembles a ring with a central pore that might be involved in substrate processing. In the hexameric configuration, the ATP-binding site is positioned at the interface between the subunits. Upon ATP binding and hydrolysis, AAA enzymes undergo conformational changes in the AAA-domains as well as in the N-domains. These motions can be transmitted to substrate protein.