Figure 2.

Methanobrevibacter smithii cell wall and cell membrane determine susceptibility to antibiotics and statins. The cell wall (violet) is composed of pseudomurein (and not murein as in bacteria) which makes archaea resistant to lysozyme and many antibiotics that interfere with cell wall synthesis. The cell membrane (ochre) consists of a lipid bilayer or monolayer the backbone of which composed of isoprene units that are linked to glycerol by ether bonds. In contrast, the lipid bilayer of bacteria consists of a fatty acid backbone that is linked to glycerol by an ester bond. The presence of statin‐sensitive isoprene units in the cell membrane of archaea allows statins to selectively interfere with the growth of archaea while leaving the cell membrane of bacteria unaffected. While bacteria do not use isoprene units in their cell membrane they are still required elsewhere. These bacterial isoprene units are, however, synthesised by a pathway (MEP) that is not inhibited by statins. See also Figure 3.