Rna polymerase sigma-70 factor, ecf subfamily; Sigma factors are initiation factors that promote the attachment of RNA polymerase (RNAP) to specific initiation sites and are then released Extracytoplasmic function (ECF) sigma-E controls the envelope stress response, responding to periplasmic protein stress, increased levels of periplasmic lipopolysaccharide (LPS) as well as heat shock and oxidative stress; it controls protein processing in the extracytoplasmic compartment. The 90 member regulon consists of the genes necessary for the synthesis and maintenance of both proteins and LPS o [...]

Serine endoprotease, periplasmic; A site-1 protease (S1P) that cleaves the peptide bond between 'Val-148' and 'Ser-149' in RseA. Part of a regulated intramembrane proteolysis (RIP) cascade. When heat shock or other environmental stresses disrupt protein folding in the periplasm, DegS senses the accumulation of unassembled outer membrane porins (OMP) and then initiates RseA (anti sigma-E factor) degradation by cleaving its periplasmic domain, making it a substrate for subsequent cleavage by RseP. This cascade ultimately leads to the sigma-E-driven expression of a variety of factors deal [...]

Soxr iron-sulfur cluster reduction factor component; May play a role in reduction of the SoxR iron-sulfur cluster. May work together with the RsxABCDGE complex

Clpxp protease specificity-enhancing factor; Enhances recognition of ssrA-tagged proteins by the ClpX-ClpP protease; the ssrA degradation tag (AANDENYALAA) is added trans- translationally to proteins that are stalled on the ribosome, freeing the ribosome and targeting stalled peptides for degradation. SspB activates the ATPase activity of ClpX. Seems to act in concert with SspA in the regulation of several proteins during exponential and stationary-phase growth

Inner membrane zinc rip metalloprotease; A site-2 regulated intramembrane protease (S2P) that cleaves the peptide bond between 'Ala-108' and 'Cys-109' in the transmembrane region of RseA. Part of a regulated intramembrane proteolysis (RIP) cascade. Acts on DegS-cleaved RseA to release the cytoplasmic domain of RseA, residue 'Val-148' of RseA may be required for this. This provides the cell with sigma-E (RpoE) activity through the proteolysis of RseA. Can also cleave sequences in transmembrane regions of other proteins (such as LacY) as well as liberated signal peptides of beta-lactamas [...]

Serine endoprotease (protease do), membrane-associated; DegP acts as a chaperone at low temperatures but switches to a peptidase (heat shock protein) at higher temperatures . Degrades transiently denatured and unfolded or misfolded proteins which accumulate in the periplasm following heat shock or other stress conditions . DegP is efficient with Val-Xaa and Ile-Xaa peptide bonds, suggesting a preference for beta-branched side chain amino acids . Only unfolded proteins devoid of disulfide bonds appear capable of being cleaved, thereby preventing non-specific proteolysis of folded protei [...]

Outer membrane porin protein c; Forms pores that allow passive diffusion of small molecules across the outer membrane. (Microbial infection) A mixed OmpC-OmpF heterotrimer is the outer membrane receptor for toxin CdiA-EC536; polymorphisms in extracellular loops 4 and 5 of OmpC confer susceptibility to CdiA- EC536-mediated toxicity

Chromate reductase, nad(p)h dehydrogenase (quinone); Catalyzes the reduction of quinones . Acts by simultaneous two-electron transfer, avoiding formation of highly reactive semiquinone intermediates and producing quinols that promote tolerance of H(2)O(2). Quinone reduction is probably the primary biological role of ChrR (By similarity). Can also reduce toxic chromate to insoluble and less toxic Cr(3+). Catalyzes the transfer of three electrons to Cr(6+) producing Cr(3+) and one electron to molecular oxygen without producing the toxic Cr(5+) species and only producing a minimal amount [...]

Acts as an auxiliary protein in the Cpx two-component envelope stress response system, helping modulate the Cpx response systems response to some inducers . Binds the periplasmic domain of sensor histidine kinase CpxA, inhibiting induction of the Cpx envelope stress response in the absence of inducer; overexpression decreases Cpx pathway activity . Some periplasmic stimulii (shown for P pili subunit PapE and probably 0.3 M NaCl) increase CpxP's susceptibility to DegP, leading to CpxP degradation, inducing the Cpx pathway . Aids in combating extracytoplasmic protein-mediated toxicity Ov [...]