Topic summary
Porins
Extracted from the Wikipedia article Porin (protein).
Diversity
Porins are also found in eukaryotes, specifically in the outer membranes of mitochondria and chloroplasts. The organelles contain general porins that are structurally and functionally similar to bacterial ones. These similarities have supported the Endosymbiotic theory, through which eukaryotic organelles arose from Gram-negative bacteria. However, eukaryotic porins exhibit the same limited diversity as Gram-positive porins, and also display a greater voltage-dependent role during metabolism.