RT Journal Article
SR Electronic
T1 Entropic effects enable life at extreme temperatures
JF Science Advances
JO Sci Adv
FD American Association for the Advancement of Science
SP eaaw4783
DO 10.1126/sciadv.aaw4783
VO 5
IS 5
A1 Kim, Young Hun
A1 Leriche, Geoffray
A1 Diraviyam, Karthik
A1 Koyanagi, Takaoki
A1 Gao, Kaifu
A1 Onofrei, David
A1 Patterson, Joseph
A1 Guha, Anirvan
A1 Gianneschi, Nathan
A1 Holland, Gregory P.
A1 Gilson, Michael K.
A1 Mayer, Michael
A1 Sept, David
A1 Yang, Jerry
YR 2019
UL http://advances.sciencemag.org/content/5/5/eaaw4783.abstract
AB Maintaining membrane integrity is a challenge at extreme temperatures. Biochemical synthesis of membrane-spanning lipids is one adaptation that organisms such as thermophilic archaea have evolved to meet this challenge and preserve vital cellular function at high temperatures. The molecular-level details of how these tethered lipids affect membrane dynamics and function, however, remain unclear. Using synthetic monolayer-forming lipids with transmembrane tethers, here, we reveal that lipid tethering makes membrane permeation an entropically controlled process that helps to limit membrane leakage at elevated temperatures relative to bilayer-forming lipid membranes. All-atom molecular dynamics simulations support a view that permeation through membranes made of tethered lipids reduces the torsional entropy of the lipids and leads to tighter lipid packing, providing a molecular interpretation for the increased transition-state entropy of leakage.