Adaptations of the archaeal cell membrane to heat stress.
In extreme environments varying from hot to cold, acidic to alkaline, and highly saline, mainly Archaea are found. Thermophilic and extremely acidophilic Archaea have a membrane that contains membrane spanning tetraether lipids. These tetra-ether membranes have a limited permeability for protons even at the high temperatures of growth and this property makes it possible for thermophilic archaea to maintain a viable proton motive force under the extreme conditions. -Ether lipids cannot be degraded easily and are highly stable which is also a requirement for life under extreme conditions. Psychrophilic and mesophilic Bacteria, and all Archaea adjust the lipid composition of their membranes so that the proton permeability of their membranes remains within a narrow range. This phenomenon is termed 'homeoproton permeability adaptation'. Thermophilic Bacteria are the only prokaryotes that are unable to control the proton permeability of their membranes. These organisms have to rely on the less permeable sodium ions in energy transducing processes in their membrane.
Albers
S V
SV
Department of Microbiology, Groningen Biomolecular Sciences and Biotechnology Institute, University of Groningen, Kerklaan 30, 9751 NN Haren, The Netherlands.
van de Vossenberg
J L
JL
Driessen
A J
AJ
Konings
W N
WN
D000222:Adaptation, Physiological; D001105:Archaea / Q000502:physiology*; D018407:Bacterial Physiological Phenomena; D001692:Biological Transport; D002462:Cell Membrane / Q000502:physiology; D018869:Heat-Shock Response; D008563:Membrane Lipids / Q000502:physiology; D008565:Membrane Proteins / Q000502:physiology
D008563:Membrane Lipids; D008565:Membrane Proteins