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Orientation Determination of Membrane-Disruptive Proteins Using Powder Samples and Rotational Diffusion: A Simple Solid-State NMR Approach.

ABSTRACT: The orientation of membrane proteins undergoing fast uniaxial rotation around the bilayer normal can be determined without macroscopic alignment. We show that the motionally averaged powder spectra exhibit their 0° frequency, [Formula: see text], at the same position as the peak of an aligned sample with the alignment axis parallel to the magnetic field. This equivalence is exploited to determine the orientation of a ?-sheet antimicrobial peptide not amenable to macroscopic alignment, using (13)CO and (15)N chemical shifts from powder spectra. This powder sample approach permits orientation determination of naturally membrane-disruptive proteins in diverse environments and under magic-angle spinning.

SUBMITTER: Hong M

PROVIDER: S-EPMC1826912 | biostudies-other | 2006 Dec

REPOSITORIES: biostudies-other

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Orientation Determination of Membrane-Disruptive Proteins Using Powder Samples and Rotational Diffusion: A Simple Solid-State NMR Approach.

Hong Mei M Doherty Tim T

Chemical physics letters 20061201 1-3

The orientation of membrane proteins undergoing fast uniaxial rotation around the bilayer normal can be determined without macroscopic alignment. We show that the motionally averaged powder spectra exhibit their 0° frequency, [Formula: see text], at the same position as the peak of an aligned sample with the alignment axis parallel to the magnetic field. This equivalence is exploited to determine the orientation of a β-sheet antimicrobial peptide not amenable to macroscopic alignment, using (13) ...[more]

PMID: 17364006

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