Some Like It Hot: The Effect of Sterols and Hopanoids on Lipid Ordering at High Temperature.
J Phys Chem Lett
; 5(22): 3953-7, 2014 Nov 20.
Article
en En
| MEDLINE
| ID: mdl-26276476
Sterols and hopanoids have been suggested to reinforce membranes and protect against unfavorable environmental conditions. In particular, hopanoids are found in high concentrations in membranes of thermotolerant and thermophilic bacteria. However, the mechanism whereby sterols and hopanoids stabilize membranes at elevated temperatures is poorly understood. Here, the effect of temperature on the ordering of lipids in bilayers containing cholesterol or the hopanoids bacteriohopanetetrol and diplopterol was explored using molecular dynamics simulations. It is shown that cholesterol induces a high level of ordering over a wide range of temperatures. Bacteriohopanetetrol promotes order within the lipid tails but enhances fluid-like properties of the head groups at high temperatures. In contrast, diplopterol partitions in the midplane of the bilayer. This suggests that individual hopanoids fulfill distinct functions in membranes, with the ordering properties of bacteriohopanetetrol being particularly well suited to maintain the integrity of membranes at temperatures preferred by thermotolerant and thermophilic bacteria.
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1
Colección:
01-internacional
Base de datos:
MEDLINE
Idioma:
En
Revista:
J Phys Chem Lett
Año:
2014
Tipo del documento:
Article
País de afiliación:
Australia
Pais de publicación:
Estados Unidos