intermembrane space

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in·ter·mem·brane space

the space between the two membranes in a cell or organelle enclosed by a double biomembrane; for example, the space between the inner and outer membranes of the mitochondria; sometimes referred to as the external matrix.
See also: external matrix.
References in periodicals archive ?
If PpPBP functions in the final step of peptidoglycan synthesis in moss plastids, similar to that in bacteria, PpPBP must localize to the intermembrane space of the plastid envelope.
Mitochondria operate a sequence of energy conversion processes through which the exergonic flow of electrons along the respiratory complexes supports the endergonic pumping of protons from the matrix to the intermembrane space.
The mitochondrial pathway is initiated by the release of apoptotic factors such as cytochrome c, apoptosis inducing factor (AIF) and endonuclease G from the mitochondrial intermembrane space by mitochondrial outer membrane permeabilization (MOMP), which is a complex process that involves numerous molecular players including Bcl-2 family (Brenner and Grimm, 2006; Kuwana and Newmeyer, 2003).
It is present in all human cells in various locations, including the cytosol, nucleus, peroxisomes, and mitochondrial intermembrane space.
This event triggers the release of pro-apoptotic proteins, including cytochrome C, from the mitochondrial intermembrane space to the cytosol where they activate caspases and endonucleases that initiates apoptosis.
In response to apoptotic stimuli, several proapoptotic proteins are released into the cytoplasm from the mitochondrial intermembrane space, including Smac/DIABLO, apoptosis-inducing factor (AIF), high temperature requirement protein A2 (HtrA2/Omi), cytochrome c, and endonuclease G.
The CK reaction catalysed by its mitochondrial isoenzyme MtCK in the mitochondrial intermembrane space is directed towards the synthesis of another high-energy phosphorus compound, phosphocreatine (PCr), which is liberated into the cytoplasm through the mitochondrial voltage-dependent anion selective channels (VDAC) leaving another reaction product, ADP, for further ATP resynthesis in the mitochondrial matrix.
These results can be explained on the basis of findings of Chattopadhya et al [10], which showed that I/R injury inhibits Bcl-2 gene expression resulting and bind to the "permeability transition pore" of mitochondrial membrane inducing loss of selective ion permeability which results in release into the cytosol intermembrane space contents including cytochrome c and apoptosis-inducing factor (AIF).
Complex I also has proton-transporting activity over the inner mitochondrial membrane to the intermembrane space.
Two type members with different membrane topologies have been described, namely, the i-AAA members which expose their catalytic site in the intermembrane space and the m-AAA which expose their catalytic sites in the mitochondrial matrix.
5) Pumping hydrogen ions into the intermembrane space decreases the pH thus producing a pH gradient as well as an electrochemical gradient.