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periplasmatischen

Periplasmatischen, typically referred to in English as the periplasmic space, is the region between the inner cytoplasmic membrane and the outer membrane of many Gram-negative bacteria. This compartment lies just inside the outer membrane and outside the cytoplasmic membrane and contains a gel-like mixture of solutes, enzymes, binding proteins, and transport components. The periplasm is distinct from the cytoplasm and the extracellular milieu. It hosts enzymes involved in nutrient acquisition and processing, such as hydrolases, phosphatases, and oxidoreductases, as well as chaperones and enzymes that form disulfide bonds in exported proteins (for example DsbA). It also contains periplasmic-binding proteins that participate in transport systems (e.g., MalE for maltose uptake) and components of secretion pathways (Sec and Tat) that shuttle proteins across the inner membrane, where they mature in the periplasm or are further exported.

The periplasm plays roles in osmotic buffering and maintenance of cell envelope integrity, and it is a

frequent
site
of
antibiotic
resistance,
as
beta-lactamases
and
other
enzymes
reside
there
to
inactivate
drugs
before
they
reach
their
targets.
In
biotechnology,
the
periplasm
is
exploited
for
disulfide-bond-rich
protein
expression
and
simplified
purification.
In
Gram-positive
bacteria,
which
lack
an
outer
membrane,
a
classic
periplasmic
space
is
not
present,
though
some
secretion-
and
envelope-associated
regions
can
serve
related
functions.