Insights into thermophilic archaebacterial membrane stability from simplified models of lipid membranes

Charles H. Davis, Huifen Nie, Nikolay V. Dokholyan

Research output: Contribution to journalArticlepeer-review

14 Scopus citations

Abstract

Lipid aggregation into fluid bilayers is an essential process for sustaining life. Simplified models of lipid structure, which allow for long time scales or large length scales not obtainable with all-atom simulations, have recently been developed and show promise for describing lipid dynamics in biological systems. Here, we describe two simplified models, a reduced-lipid model and a bola-lipid model for thermophilic bacterial membranes, developed for use with the rapid discrete molecular dynamics simulation method. In the reduced-lipid model, we represent the lipid chain by a series of three beads interacting through pairwise discrete potentials that model hydrophobic attractions between hydrocarbon tails in implicit solvent. Our phase diagram recapitulates those produced by continuous potential models with similar coarse-grained lipid representations. We also find that phase transition temperatures for our reduced-lipid model are dependent upon the flexibility of the lipid chain, giving an insight into archaebacterial membrane stability and prompting development of a bola-lipid model specific for archaebacteria lipids. With both the reduced-lipid and bola-lipid model, we find that the reduced flexibility inherent in archaebacteria lipids yields more stable bilayers as manifested by increased phase transition temperatures. The results of these studies provide a simulation methodology for lipid molecules in biological systems and show that discrete molecular dynamics is applicable to lipid aggregation and dynamics.

Original languageEnglish (US)
Article number051921
JournalPhysical Review E - Statistical, Nonlinear, and Soft Matter Physics
Volume75
Issue number5
DOIs
StatePublished - May 30 2007

All Science Journal Classification (ASJC) codes

  • Statistical and Nonlinear Physics
  • Statistics and Probability
  • Condensed Matter Physics

Fingerprint Dive into the research topics of 'Insights into thermophilic archaebacterial membrane stability from simplified models of lipid membranes'. Together they form a unique fingerprint.

Cite this