Identiˆcation and Classiˆcation of Two-component Systems That AŠect rpoS Expression in Escherichia coli

CONSTRUCTION OF RECOMBINANT PLASMIDS FOR PERIPLASMIC EXPRESSION OF HUMAN GROWTH HORMONE IN ESCHERICHIA COLI UNDER T7 AND LAC PROMOTERS

In order to study the periplasmic expression of human growth hormone (hGH) in Escherichia coli, the related cDNA was inserted in two expression plasmids carrying pelB signal peptide, one with lac bacterial promoter and the other with a bacteriophage T7-based promoter. The recombinant plasmids were moved to TG1 and BL21 strains of E. coli, respectively. To induce the expression systems, IPTG and...

Comparison of T7- and Lac-Based Systems for the Periplasmic Expression of Human Granulocyte Macrophage Colony Stimulating Factor in Escherichia coli

The PhoP/PhoQ two-component system stabilizes the alternative sigma factor RpoS in Salmonella enterica.

The sigma factor RpoS regulates the expression of many stress response genes and is required for virulence in several bacterial species. We now report that RpoS accumulates when Salmonella enterica serovar Typhimurium is growing logarithmically in media with low Mg(2+) concentrations. This process requires the two-component regulatory system PhoP/PhoQ, which is specifically activated in low Mg(...

Controlled expression of an rpoS antisense RNA can inhibit RpoS function in Escherichia coli.

We show that an inducible rpoS antisense RNA complementary to the rpoS message can inhibit expression of RpoS in both exponential and stationary phases and can attenuate expression of the rpoS regulon in Escherichia coli. Plasmids containing rpoS antisense DNA expressed under the control of the T7lac promoter and T7 RNA polymerase were constructed, and expression of the rpoS antisense RNA was o...

Cloning and evaluation of gene expression and purification of gene encoding recombinant protein containing binding subunit of coli surface antigens CS1 and CS2 from Enterotoxigenic Escherichia coli

Background & Objective: Enterotoxigenic Escherichia coli (ETEC) is a major causative agent of diarrhea. Enterotoxins and the colonization factors (CFs) are major virulence factors in ETEC infections. The bacterium binds to the intestinal epithelial cell surface through colonization factors and produces enterotoxins that cause excessive fluid and electrolyte secretion in the lumen of the intesti...