Examining Protein–Lipid Complexes Using Neutron Scattering

  • Luke A. Clifton
  • Cameron Neylon
  • Jeremy H. Lakey
Part of the Methods in Molecular Biology book series (MIMB, volume 974)


Studying the structure of protein–lipid complexes, be they in vesicles, planar bilayers, monolayers, or nanodiscs, poses two particular challenges. Firstly such complexes are often dynamic. Secondly we need to resolve the lipid and protein structures within the complex. Neutron scattering is well placed to help in both respects since it deals with molecules in large, complex, dynamic structures and can easily differentiate between different molecular species. This comes from the great penetrating power of neutrons and their sensitivity to the difference between hydrogen (H) and deuterium (D). Both membrane proteins and lipids can be produced with varying degrees of deuteration, thus allowing us to dissect complexes with great accuracy. Two main scattering techniques are immediately applicable to the study of protein–lipid interactions. Neutron reflection exploits the constructive interference, which occurs when neutrons are reflected from different points in a layer. An everyday example is the rainbow of colors reflected from an oil film on water, which result from varying film thickness and the angle of reflection. Neutrons because of their short wavelengths (4–15 Å) and H/D sensitivity can, in reflectometry mode, provide accurate cross sections of lipid monolayers and bilayers. Small-angle neutron scattering (SANS) can resolve the structures of protein–lipid complexes if they are present as homogeneous dispersions. This is easiest with detergent micelles, but increasingly methods are being developed whereby vesicles, nanodiscs, etc., can be resolved. Again the ability to deuterate proteins and lipids enables SANS to resolve the inner structure of big, dynamic, lipid–protein complexes. The recent introduction of advanced neutron beam lines means that the technique is now within the grasp of a broad cross section of researchers.

Key words

Neutron scattering Reflectometry Small-angle scattering Protein–lipid complexes Deuteration Lipid monolayers 



We thank John Webster for helping in providing helpful advice on instrumentation and data modeling procedures.


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Copyright information

© Springer Science+Business Media New York 2013

Authors and Affiliations

  • Luke A. Clifton
    • 1
  • Cameron Neylon
    • 2
  • Jeremy H. Lakey
    • 3
  1. 1.Large Scale Structures GroupISIS Spallation Neutron Source, Harwell Science and Innovation Campus, Rutherford Appleton Laboratory, DidcotOxfordshireUK
  2. 2.Science and Technology Facilities CouncilISIS Spallation Neutron Source, Harwell Science and Innovation Campus, Rutherford Appleton Laboratory, DidcotOxfordshireUK
  3. 3.Institute for Cell and Molecular BiosciencesNewcastle UniversityNewcastle upon TyneUK

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