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The space between the cell membranes and the cell wall, in gram-negative bacteria; contains proteins secreted by the cell.
Farlex Partner Medical Dictionary © Farlex 2012


The region between the cytoplasmic membrane and the outer cell membrane in gram-negative bacteria and some archaea.

per′i·plas′mic adj.
The American Heritage® Medical Dictionary Copyright © 2007, 2004 by Houghton Mifflin Company. Published by Houghton Mifflin Company. All rights reserved.
References in periodicals archive ?
Kahne, "Cytoplasmic ATP hydrolysis powers transport of lipopolysaccharide across the periplasm in E.
They found that varying the length of the LppA protein varied the width of the periplasm along with the length of the rod.
Based on the origin of plastids from an endosymbiotic cyanobacterium, PpPBP must localize to the intermembrane space where peptidoglycan is present, because PBPs function in the periplasm where new peptidoglycan monomer units join pre-existing peptidoglycans in bacteria.
As bdellovibrio enters the prey periplasm, the flagellar motility stops and then it sheds its flagellum.
The well-characterized lipoprotein Lpp from Escherichia coli is present in two different orientations within the bacterial outer membrane: either exposed to the periplasm or the bacterial surface (1).
The periplasm of Gram-negative bacteria is a hydrated gel located between the cytoplasmic and outer membranes and is comprised of peptidoglycan (cell wall), proteins, carbohydrates, and small solutes [1-3].
ESETECE.coli (Wacher Biotech): ESETEC secretes recombinant protein products into the culture broth, which obviates isolation from the periplasm. Extracellular transportation of properly folded proteins occurs via the Secretory (Sec) pathway.
Furthermore, the substantial synergy of the OA/Ap combination in preventing the growth of non-pathogenic Escherichia colt MC1061 cannot be explained by inhibition of [beta]-lactamase translocation to the periplasm, since this was found to be diminished by only 25%.
This system comprises more than a dozen interacting proteins and serves to export toxin and other proteins such as extracellular enzymes from the periplasm across the outer membrane (25).
Spirochetes are motile, helical gram-negative eubacteria whose flagella rotate between the outer and inner plasma membrane (in the periplasm).
Since periplasmic targeting of antigens has been shown to be effective in delivering heterologous antigens, we investigated whether the expression of chlamydial outer membrane protein, PorB, in the periplasm of VCG would lead to a robust antigen expression.
The PhoA component of this fusion construct shows whether IcsA has been secreted across the cytoplasmic membrane to the periplasm of Shigella since the PhoA is only active in the periplasm.