Water Replacement Hypothesis in Atomic Details: Effect of Trehalose on the Structure of Single Dehydrated POPC Bilayers

E.A. Golovina, A. Golovin, F.A. Hoekstra, R. Faller

Research output: Contribution to journalArticleAcademicpeer-review

54 Citations (Scopus)

Abstract

We present molecular dynamics (MD) simulations to study the plausibility of the water replacement hypothesis (WRH) from the viewpoint of structural chemistry. A total of 256 2-oleoyl-1-palmitoyl-sn-glycero-3-phosphocholine (POPC) lipids were modeled for 400 ns at 11.7 or 5.4 waters/lipid. To obtain a single dehydrated bilayer relevant to the WRH, simulations were performed in the NPxyhzT ensemble with hz > 8 nm, allowing interactions between lipids in the membrane plane and preventing interactions between neighboring membranes via periodic boundary conditions. This setup resulted in a stable single bilayer in (or near) the gel state. Trehalose caused a concentration-dependent increase of the area per lipid (APL) accompanied by fluidizing the bilayer core. This mechanism has been suggested by the WRH. However, dehydrated bilayers in the presence of trehalose were not structurally identical to fully hydrated bilayers. The headgroup vector was in a more parallel orientation in dehydrated bilayers with respect to the bilayer plane and maintained this orientation in the presence of trehalose in spite of APL increase. The total dipole potential changed sign in dehydrated bilayers and remained slightly positive in the presence of trehalose. The model of a dehydrated bilayer presented here allows the study of the mechanisms of membrane protection against desiccation by different compounds
Original languageEnglish
Pages (from-to)11118-11126
JournalLangmuir
Volume26
Issue number13
DOIs
Publication statusPublished - 2010

Keywords

  • molecular-dynamics simulation
  • x-ray-diffraction
  • lea-like protein
  • solid-state nmr
  • lipid-bilayers
  • phospholipid-bilayer
  • dipalmitoylphosphatidylcholine multilayers
  • saccharomyces-cerevisiae
  • phase-behavior
  • low hydration

Fingerprint

Dive into the research topics of 'Water Replacement Hypothesis in Atomic Details: Effect of Trehalose on the Structure of Single Dehydrated POPC Bilayers'. Together they form a unique fingerprint.

Cite this