They displayed intact outer membrane and cytoplasmic membrane enclosing a periplasmic space and centrally placed nucleoid containing fine DNA fibrils (Fig.
coli cells grown on normal medium showed the cell wall composed of outer and cytoplasm membranes enclosing a periplasmic space, the nucleoid containing fine DNA fibril and the cytoplasm containing numerous ribosomes.
Subsequently, proteins were isolated from the periplasmic space (samples A and B, supernatant and pellet, respectively) and were analyzed using SDS-PAGE.
One important advantage of pBAD/g A plasmid used in the present study is the addition of signal sequence to the N-terminal segment of reteplase enabling it to be secreted into the periplasmic space. This would provide a better environment for proper folding of this enzyme (21).
Similarly, Shiga toxin was also found to be released as OMVs from periplasmic space
of Shigella dysenteriae and that the secretion was induced by an antimicrobial compound, mitomycin C (43).
The secretion of recombinant proteins to the E.coli periplasmic space may eliminate these drawbacks (14-16).
In this system, the signal sequence, pelB, is responsible for the secretion of protein into the periplasmic space. In the cell pellet fraction the prominently expressed protein was the B2BMP-7 pre-protein (pelB-hB2BMP-7).
Confirmation of extracted outer membrane proteins (OMPs) and recombinant protein CagA by SDS-PAGE and western blotting Finally, to check that the recombinant protein CagA was in the supernatant (periplasmic space
) or pellet (inclusion bodies) and for confirmation of extracted outer membrane proteins SDS-PAGE was performed.
Although disulfide bond formation usually takes place in periplasmic space
, tPA secreted in the periplasm of E.