THE ESSENCE OF BEING EXTREMOPHILIC - THE ROLE OF THE UNIQUE ARCHAEAL MEMBRANE-LIPIDS

In extreme environments, mainly Archaea are encountered. The archaeal cytoplasmic membrane contains unique ether lipids that cannot easily b e degraded, are temperature- and mechanically resistant, and highly sa lt tolerant. Moreover, thermophilic and extreme acidophilic Archaea po ssess membrane-spanning tetraether lipids that form a rigid monolayer membrane which is nearly impermeable to ions and protons. These proper ties make the archaeal lipid membranes more suitable for life and surv ival in extreme environments than the ester-type bilayer lipids of Bac teria or Eukarya.