The antimicrobial impact of cinnamaldehyde (a non-phenolic phenylpropene and main active compound of cinnamon) in suggested to arise through its carbonyl group interaction with proteins in the periplasm
and inactivation microbial enzymes (Burt, 2004).
Moreover, OMVs can be engineered by delivering recombinant proteins to bacterial periplasm
and outer membrane.
They saw that the mechanism consists of two separate complexes, one in the outer membrane of the cell, and the other in the inner membrane, which are connected by a stalk-like structure that crosses the periplasm
- the space between the two membranes.
The Sec pathway transports proteins from the cytoplasm to the periplasm
in an unfolded state; consequently, proteins that require a cytoplasmic environment and/or cytoplasmic components for folding, or reach their native state before they interact with the Sec proteins, are not compatible with the Sec pathway.
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).
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%.
And to make things worse MscL and MscS span the plasma membrane, which means that their ends, which are exposed to the periplasm
outside the cell and the cytoplasm inside the cell, are water-loving and their middle sections, which are stuck in the greasy membrane, are repelled by water.
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).