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I would like to know if there is any difference in chemical composition of cellular bilayer lipid membrane between eukaryotes and prokaryotes.

Specifically, I would like to know about the action of antimicrobial peptides on these bilayer membranes in context of the different membrane compositions.

It would be helpful if someone points me to some references.

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    $\begingroup$ I have given some references that let you discuss variations in membrane compositions. There are many more. I think for a more productive answer you need to talk about specific species. $\endgroup$
    – James
    Commented Sep 12, 2016 at 11:10
  • $\begingroup$ Prokaryotes include archaebacteria. Some archaebacteria shows ether-bridge (instead ester bridge) between glycerol and fatty-acid. Even in some cases in some archaebacteria, instead 2 layer of lipid there is 1 layer of lipid whose each molecule have 2 heads. Also, gram-negative eubacteria is wrapped with 2 membranes- the cell membrane and outer membrane. $\endgroup$
    – user25568
    Commented Sep 14, 2016 at 13:49
  • $\begingroup$ But the basic-plan of cell-membrane of any-cell is the exact same... whatever it is prokaryote or eukaryote... exact same. Few scanty exceptional cases also, basically obey the physics rule of normal membranes of eukaryotes and prokaryotes. $\endgroup$
    – user25568
    Commented Sep 14, 2016 at 13:51

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There are differences. (Except mitochondrial eukaryotic membranes, which are indeed similar to bacterial membranes! (reviewed in van Meer et al., 2008)).

First, bare in mind that it is thought that even different eukaryotes, such as Fungi and Humans, have different cell membrane compositions and that this is reflected in the proteins (Sharpe et al, 2010). The outer membrane of Gram negative bacteria isn't even made of phospholipids, it's made of glycolipids (Kamio & Nikaido, 1976). Archean membranes have the most notable lipid compositions, including a bilayer-like monolayer, to adapt to the conditions they are found in (Oger et al 2013). My point being that saying "there are differences" is indeed an understatement.

This question has probably arisen because anti-microbial peptides seem to act with specificity, and that perhaps this specificity comes from direct peptide-lipid interaction. This is on the right lines. From wikipedia:

The cell membranes of bacteria are rich in acidic phospholipids, such as phosphatidylglycerol and cardiolipin[23][27]. These phospholipid headgroups are heavily negatively charged. Therefore, the outmost leaflets of the bilayer which is exposed to the outside of the bacterial membranes are more attractive to the attack of the positively charged antimicrobial peptides.

Notably, no such charge exists in eukaryotes since the negative charge is found on the inner leaflet of the plasma-membrane rather than the outer leaflet.

There is such a massive variation, even within bacterial membrane composition (Bogdanov et al 2014), that I cannot even really begin to list it here. Furthermore, there are variations in the glycocalyx, surface proteins, and lipid composition dynamics due to lipid rafts.

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