Putative endopeptidase; Membrane-localized protease able to endoproteolytically degrade overproduced SecY but not YccA, another membrane protein. It seems to cleave SecY at specific cytoplasmic sites. Does not require ATP. Its natural substrate has not been identified. Probably plays a role in the quality control of integral membrane proteins. Belongs to the peptidase M48B family.

Protease, ATP-dependent zinc-metallo; 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. Degrades a few membrane proteins that have not been assembled into complexes such as SecY, F(0) ATPase subunit a and YccA, and also cytoplasmic proteins sigma-32, LpxC, KdtA and phage lambda cII protein among others. Degrades membrane proteins in a processive manner starting at either the N- or C-terminus; recognition requires a cytoplasmic tail of about 20 residues with no apparent [...]

BAX Inhibitor-1 family inner membrane protein.

Periplasmic ATP-independent protein refolding chaperone, stress-induced; An ATP-independent periplasmic chaperone, decreases protein aggregation and helps protein refolding. Binds substrate over a large region of its convex inner surface. Substrate protein folds while it is bound to chaperone. Increasing Spy flexibility increases its substrate affinity and overall chaperone activity (shown for 3 different substrates). Protects proteins in vitro against tannin inactivation; tannins have antimicrobial activity. Overexpression enhances the stability of otherwise unstable periplasmic prote [...]

DUF533 family inner membrane protein.

Preprotein translocase membrane subunit; The central subunit of the protein translocation channel SecYEG. Consists of two halves formed by TMs 1-5 and 6-10. These two domains form a lateral gate at the front which open onto the bilayer between TMs 2 and 7, and are clamped together by SecE at the back. The channel is closed by both a pore ring composed of hydrophobic SecY resides and a short helix (helix 2A) on the extracellular side of the membrane which forms a plug. The plug probably moves laterally to allow the channel to open. The ring and the pore may move independently. SecY is r [...]

L,D-transpeptidase linking Lpp to murein; Responsible, at least in part, for anchoring of the major outer membrane lipoprotein (Lpp, also known as the Braun lipoprotein) to the peptidoglycan via a meso-diaminopimelyl-L-Lys- bond on the terminal residue of Lpp.

Modulator for HflB protease specific for phage lambda cII repressor; HflC and HflK help govern the stability of phage lambda cII protein, and thereby control the lysogenization frequency of phage lambda. HflKC inhibits the SecY-degrading activity of FtsH, possibly helping quality control of integral membrane proteins. Belongs to the band 7/mec-2 family. HflK subfamily.

Heat shock protein involved in degradation of mutant DnaA; Involved in the degradation of certain denaturated proteins, including DnaA, during heat shock stress.