Cookies on this website
We use cookies to ensure that we give you the best experience on our website. If you click 'Continue' we'll assume that you are happy to receive all cookies and you won't see this message again. Click 'Find out more' for information on how to change your cookie settings.

Structural models of membrane proteins can be refined with sets of multiple orientation constraints derived from structural NMR studies of specifically labeled amino acids. The magic angle oriented sample spinning (MAOSS) NMR approach was used to determine a set of orientational constraints in bacteriorhodopsin (bR) in the purple membrane (PM). This method combines the benefits of magic angle spinning (MAS), i.e., improved sensitivity and resolution, with the ability to measure the orientation of anisotropic interactions, which provide important structural information. The nine methionine residues in bacteriorhodopsin were isotopically (15)N labeled and spectra simplified by deuterium exchange before cross-polarization magic angle spinning (CPMAS) experiments. The orientation of the principal axes of the (15)N chemical shift anisotropy (CSA) tensors was determined with respect to the membrane normal for five of six residual resonances by analysis of relative spinning sideband intensities. The applicability of this approach to large proteins embedded in a membrane environment is discussed in light of these results.

Original publication

DOI

10.1016/S0006-3495(04)74228-9

Type

Journal article

Journal

Biophys J

Publication Date

03/2004

Volume

86

Pages

1610 - 1617

Keywords

Algorithms, Anisotropy, Bacteriorhodopsins, Computer Simulation, Halobacterium salinarum, Magnetic Resonance Spectroscopy, Membrane Fluidity, Membrane Proteins, Models, Molecular, Nitrogen Isotopes, Protein Conformation, Purple Membrane, Spin Labels