In Escherichia coli, the CpxR/A two-component system senses various types of extracytoplasmic stresses and responds by activating the expression of genes encoding periplasmic protein folding and trafficking factors that clear such stresses to ensure the organism's survival. The cpxP gene encodes a small, stress-combative periplasmic protein and is the most strongly induced member of the Cpx reg...

DegS, the periplasmic stress sensor, becomes activated when its PDZ domain recognizes the improperly exposed C-terminal sequences of outer membrane porins. This interaction relieves the inhibition of the neighboring protease domain of DegS, triggering a proteolysis cascade that leads to the sigma(E)-driven expression of periplasmic chaperones.

We have developed a bacterial system for the discovery of interacting proteins that, unlike other two-hybrid technologies, allows for the selection of protein pairs on the basis of affinity or expression. This technology relies on the anchored periplasmic expression (APEx) of one protein (bait) on the periplasmic side of the inner membrane of Escherichia coli and its interacting partner (prey) ...

knowing the nucleotide sequence of the cholera toxin operon, we designed oligonucleotide primers for its-pcr amplification from local clinical isolates of v. cholerae. the resulting amplification product was cloned in a common puc18 vector. subsequently, a part of this operon encoding the cholera toxin bsubunit (ctb) was reamplified and cloned between the bamh1 and ecor1 sites of the same vecto...

Knowing the nucleotide sequence of the cholera toxin operon, we designed oligonucleotide primers for its-PCR amplification from local clinical isolates of V. cholerae. The resulting amplification product was cloned in a common pUC18 vector. Subsequently, a part of this operon encoding the cholera toxin Bsubunit (CTB) was reamplified and cloned between the BamH1 and EcoR1 sites of the same ...

with the aim of the secretion of human granulocyte macrophage-colony stimulating factor (hgm-csf) in escherichia coli, hgm-csf cdna was fused in-frame next to the signal sequence of st toxin (st-i) of exteroxigenic e. coli, containing 53 or 19 amino acids of signal peptide. the fused stsig::hgm-csf coding fragments were inserted into a t7-based expression plasmid. the recombinant plasmids were ...

purpose: in order to express human granulocyte-macrophage colony stimulating factor (hgm-csf) under heat shock. materials and methods: two expression plasmids were constructed based on pbc(sk) plasmid. the expression cassettes in the two plasmids are equipped with a 75 base pair fragment, derived from the pl promoter of the bacteriophage lambda (λ). the plasmids also contain a temperature muta...

The periplasm of Gram-negative bacteria is a dynamic and physiologically important subcellular compartment where the constant exposure to potential environmental insults amplifies the need for proper protein folding and modifications. Top-down proteomics analysis of the periplasmic fraction at the intact protein level provides unrestricted characterization and annotation of the periplasmic prot...

Auto-inducible promoter systems have been reported to increase soluble product formation in the periplasm of E. coli compared inducer-dependent systems. In this study, we investigated phosphate (PO4)-sensitive phoA expression system (pAT) for production a recombinant model antigen-binding fragment (Fab) detail. We explored impact non-limiting and limiting PO4 conditions on strain physiology as ...

ToxR is a bitopic membrane protein that controls virulence gene expression in Vibrio cholerae. Its cytoplasmic domain is homologous to the winged helix-turn-helix ('winged helix') DNA-binding/transcription activation domain found in a variety of prokaryotic and eukaryotic regulators, whereas its periplasmic domain is of ill-defined function. Several genes in V. cholerae are regulated by ToxR, b...