Neutron diffraction with an excess-water cell

Thad A. Harroun, Kia Balai-Mood, Thomas Hauß, Toshiya Otomo, Jeremy P. Bradshaw

Research output: Contribution to journalArticle

2 Citations (Scopus)

Abstract

As part of a study of the molecular basis of membrane fusion by enveloped viruses, we have used neutron diffraction to study the lamellar (L α) to inverse hexagonal (H II) phase transition in the phospholipid N-methylated dioleoylphosphatidylethanolamine. This lipid was chosen because its phase transitions are particularly sensitive to the presence of agents that have been demonstrated to promote or inhibit membrane fusion. Two different geometries of neutron diffraction were used: small angle scattering (SANS) and a membrane diffractometer. The SANS measurements were carried out on the SWAN instrument at KEK, Japan, using dispersions of multilamellar vesicles (MLVs). The diffractometer measurements used the V1 instrument at BeNSC-HMI, Germany, with a specially-constructed cell that holds a stack of lipid bilayers in an excess-water state. The two approaches are compared and discussed. Although the diffractometer takes considerably longer to collect the data, it records much higher resolution than the SANS instrument. The samples recorded in the excess-water cell were shown to be well aligned, despite the lipids being fully hydrated, allowing for the production of high-resolution data. Trial measurements performed have demonstrated that sample alignment is preserved throughout the L α to H II phase transition, thereby opening up possibilities for obtaining high-resolution data from non-lamellar phases.

Original languageEnglish
Pages (from-to)207-218
Number of pages12
JournalJournal of Biological Physics
Volume31
Issue number2
DOIs
Publication statusPublished - 1 May 2005

Keywords

  • Cubic phase
  • Inverse hexagonal phase
  • Lamellar phase
  • Neutron diffraction
  • Phase transitions
  • Phospholipids

ASJC Scopus subject areas

  • Biophysics
  • Atomic and Molecular Physics, and Optics
  • Molecular Biology
  • Cell Biology

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