Metalloprotease that cleaves substrates preferentially between Phe-Phe residues. Plays a role in response to some stress conditions. Seems to regulate the expression of speB. Binds 1 zinc ion per subunit. Interacts with Era and BepA. Proper membrane localization can depend on BepA. Induced by heat shock and low osmolarity. The intramolecular disulfide bond improves the stability and the activity of LoiP. It forms even in the absence of the oxido-reductase DsbA (PubMed:22491786). Belongs to the peptidase M48B family. Extended N-terminus. Extended N-terminus.