A self-regulated high-copy number plasmid containing chloramphenicol resistant gene, for the production of recombinant proteins under the regulation of bacteriophage ?pL promoter, was constructed. The designed 5024 base pair expression plasmid contained a heat sensitive repressor cI857 coding gene to regulate the function of ?pL promoter under heat shock induction. Using the constructed vector,...

Gram-negative bacteria are surrounded by two membrane bilayers separated by a space termed the periplasm. The periplasm is a multipurpose compartment separate from the cytoplasm whose distinct reducing environment allows more efficient and diverse mechanisms of protein oxidation, folding, and quality control. The periplasm also contains structural elements and important environmental sensing mo...

Recombinant Escherichia coli systems expressing organophosphorous hydrolase (OPH) have been proposed for biotransformation of toxic organophosphate compounds. However, whole cell biocatalyst systems are critically disadvantaged due to substrate diffusion limitations. To enhance whole cell biocatalytic efficiency, we engineered E. coli, for the first time, to secrete metal ion cofactor-requiring...

a self-regulated high-copy number plasmid containing chloramphenicol resistant gene, for the production of recombinant proteins under the regulation of bacteriophage ?pl promoter, was constructed. the designed 5024 base pair expression plasmid contained a heat sensitive repressor ci857 coding gene to regulate the function of ?pl promoter under heat shock induction. using the constructed vector,...

background: bone morphogenetic proteins (bmps) belong to the transforming growth factor-β (tgf-β) superfamily, and play an important role in bone metabolism. recombinant forms of bmp-2 and bmp-7 are the only bmps used clinically. in this study the mature part of human bone morphogenetic protein-7 (bmp-7) was engineered through substitution of the bmp-7 n-terminal sequence by heparin-binding sit...

conclusions the activities studied by the production of pnp were determined by following the increase at 410 nm. the maximum pnp was produced at 30°c with an optical density of 10.62 in the presence of cytoplasmic expression of oph (pet21a-opd). consequently, our results suggest cytoplasmic expression system as an appropriate candidate with a high amount of oph in spite of inclusion body format...

FtsH is a membrane-bound and ATP-dependent protease of Escherichia coli, known to degrade SecY, a membrane protein for protein translocation, and CII, a soluble transcription factor for lysis/lysogeny decision of phage lambda. FtsH forms a homo-oligomeric complex as well as a hetero-oligomeric complex with HflKC, a putative modulator of FtsH. Although FtsH has a small periplasmic region, HflKC ...

LacY mutant Cys154 → Gly exhibits a periplasmic-closed crystal structure identical to the WT, but is periplasmic-open in the membrane. The mutant hardly catalyzes transport, but binds galactosides from either side of the membrane with the same affinity and is resistant to site-directed proteolysis relative to the pseudo-WT. Site-directed alkylation was also applied to 11 single-Cys mutants in C...

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...