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 ...

Abstract The human prolactin antagonist ? 1-11 -G129R-hPRL is a 21.9 kDa recombinant protein with 188 amino acids that downregulates the proliferation of variety cells expressing receptors. Periplasmic expression proteins in E. coli has been considered an option for obtaining soluble and correctly folded protein, as alternative to cytoplasmic production. aim this work was, therefore, synthesize...

recombinant protein production in e. coli has several advantages over other expression systems. misfolding, inclusion body formation, and lack of eukaryotic post translational modification are the most disadvantages of this system. exporting of correctly folded proteins to the outside of reductive cytoplasmic environment through twin-arginine system could help to pass these limiting steps. two ...

The lipopolysaccharide (LPS) transport (Lpt) system is responsible for transferring LPS from the periplasmic surface of the inner membrane (IM) to the outer leaflet of the outer membrane (OM), where it plays a crucial role in OM selective permeability. In E. coli seven essential proteins are assembled in an Lpt trans-envelope complex, which is conserved in γ-Proteobacteria. LptBFG constitute th...

Expression of recombinant proteins outside the cytoplasm was pioneered over 20 years ago in bacterial and yeast systems [1-3], opening the way for its current use in a variety of biotechnological applications [4]. The bacterium Escherichia coli remains the preferred host for the extracytoplasmic expression of recombinant proteins because of its compartmentalized cell envelope, which comprises t...

The Cpx envelope stress response is induced by the misfolding of periplasmic proteins and restores envelope homeostasis by upregulating several periplasmic protein folding and degrading factors. The Cpx response also regulates the expression of a variety of envelope-spanning protein complexes, including flagella, secretion systems and pili, which play an important role in pathogenesis. In a pre...

Gram-negative bacteria export a large variety of antimicrobial compounds by forming two-membrane spanning tripartite multidrug efflux systems composed an inner membrane transporter, outer channel and periplasmic adaptor protein. Here we present the co-expression, purification first electron microscopy insights Escherichia coli EmrAB–TolC Major Facilitator Superfamily (MSF) system as whole compl...

The expression of heterologous secreted proteins in Escherichia coli is widely employed for laboratory and preparative purposes. Thanks to advances in expression technologies over the past 25 years, many mammalian proteins can now be produced routinely in secreted form with yields in the gram/litre scale. Nonetheless, ensuring efficient secretion across the inner membrane, and preventing proteo...

BACKGROUND Organophosphorus hydrolase (OPH) is a type of organophosphate-degrading enzyme which is widely used in the bioremediation process. OBJECTIVES In this study, the periplasmic and cytoplasmic productions and the activity of recombinant OPH in Escherichia coli were investigated and compared using two pET systems (pET21a and pET26b). MATERIALS AND METHODS The sequence encoding the opd...

Human Interferon β (INF-β) is a member of cytokines family which different studies have shown its immunomodulatory and antiviral activities. In this study an expression vector was designed and constructed for expression of human INF-β-1b either in shake flasks or bench top bioreactor. The designed vector was constructed based upon pET-25b(+) with T7 promoter. Recombinant human beta interferon (...