Acts as a processive, ATP-dependent zinc metallopeptidase for both cytoplasmic and membrane proteins. Plays a role in the quality control of integral membrane proteins. Complements an E.coli null mutation. Upon overexpression in E.coli has been shown to degrade endogenous sigma-32, SecY and phage lambda cII protein. Binds 1 zinc ion per subunit. Homohexamer. Upon expression in E.coli. In the central section; belongs to the AAA ATPase family. In the C-terminal section; belongs to the peptidase M41 family.