Format

Send to

Choose Destination
Biochim Biophys Acta. 2015 Jan;1848(1 Pt B):229-45. doi: 10.1016/j.bbamem.2014.04.002. Epub 2014 Apr 18.

Membrane protein structure from rotational diffusion.

Author information

1
Department of Chemistry and Biochemistry, University of California San Diego, La Jolla, CA 92093-0307 USA.
2
Department of Chemistry and Biochemistry, University of California San Diego, La Jolla, CA 92093-0307 USA. Electronic address: sopella@ucsd.edu.

Abstract

The motional averaging of powder pattern line shapes is one of the most fundamental aspects of sold-state NMR. Since membrane proteins in liquid crystalline phospholipid bilayers undergo fast rotational diffusion, all of the signals reflect the angles of the principal axes of their dipole-dipole and chemical shift tensors with respect to the axis defined by the bilayer normal. The frequency span and sign of the axially symmetric powder patterns that result from motional averaging about a common axis provide sufficient structural restraints for the calculation of the three-dimensional structure of a membrane protein in a phospholipid bilayer environment. The method is referred to as rotationally aligned (RA) solid-state NMR and demonstrated with results on full-length, unmodified membrane proteins with one, two, and seven trans-membrane helices. RA solid-state NMR is complementary to other solid-state NMR methods, in particular oriented sample (OS) solid-state NMR of stationary, aligned samples. Structural distortions of membrane proteins from the truncations of terminal residues and other sequence modifications, and the use of detergent micelles instead of phospholipid bilayers have also been demonstrated. Thus, it is highly advantageous to determine the structures of unmodified membrane proteins in liquid crystalline phospholipid bilayers under physiological conditions. RA solid-state NMR provides a general method for obtaining accurate and precise structures of membrane proteins under near-native conditions.

KEYWORDS:

Membrane protein; NMR spectroscopy; Phospholipid bilayer; Protein structure determination; Rotational diffusion

PMID:
24747039
PMCID:
PMC4201901
DOI:
10.1016/j.bbamem.2014.04.002
[Indexed for MEDLINE]
Free PMC Article

Supplemental Content

Full text links

Icon for Elsevier Science Icon for PubMed Central
Loading ...
Support Center