Результаты исследований: Научные публикации в периодических изданиях › Обзорная статья › Рецензирование
Solid-State 2H NMR spectroscopy of retinal proteins in aligned membranes. / Brown, Michael F.; Heyn, Maarten P.; Job, Constantin; Kim, Suhkmann; Moltke, Stephan; Nakanishi, Koji; Nevzorov, Alexander A.; Struts, Andrey V.; Salgado, Gilmar F.J.; Wallat, Ingrid.
в: Biochimica et Biophysica Acta - Biomembranes, Том 1768, № 12, 12.2007, стр. 2979-3000.Результаты исследований: Научные публикации в периодических изданиях › Обзорная статья › Рецензирование
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TY - JOUR
T1 - Solid-State 2H NMR spectroscopy of retinal proteins in aligned membranes
AU - Brown, Michael F.
AU - Heyn, Maarten P.
AU - Job, Constantin
AU - Kim, Suhkmann
AU - Moltke, Stephan
AU - Nakanishi, Koji
AU - Nevzorov, Alexander A.
AU - Struts, Andrey V.
AU - Salgado, Gilmar F.J.
AU - Wallat, Ingrid
N1 - Funding Information: Research described in this article was supported by NIH grants EY 12049 (M. F. B.) and GM 36564 (K. N.), NSF grant CHE-607917 (M.F.B.), and by Deutsche Forschungsgemeinschaft grant Sfb 498 (M. P. H.). We are especially grateful to our colleagues and laboratory members for their many contributions to this work. Organic synthesis of retinal benefited from the collaboration of S. Krane, N. Fujioka, N. Sakai, and K. Tanaka whose efforts are warmly acknowledged. We also express our appreciation to R. Bogomolni and W. L. Hubbell for stimulating discussions. Copyright: Copyright 2008 Elsevier B.V., All rights reserved.
PY - 2007/12
Y1 - 2007/12
N2 - Solid-state 2H NMR spectroscopy gives a powerful avenue to investigating the structures of ligands and cofactors bound to integral membrane proteins. For bacteriorhodopsin (bR) and rhodopsin, retinal was site-specifically labeled by deuteration of the methyl groups followed by regeneration of the apoprotein. 2H NMR studies of aligned membrane samples were conducted under conditions where rotational and translational diffusion of the protein were absent on the NMR time scale. The theoretical lineshape treatment involved a static axial distribution of rotating C-C2H3 groups about the local membrane frame, together with the static axial distribution of the local normal relative to the average normal. Simulation of solid-state 2H NMR lineshapes gave both the methyl group orientations and the alignment disorder (mosaic spread) of the membrane stack. The methyl bond orientations provided the angular restraints for structural analysis. In the case of bR the retinal chromophore is nearly planar in the dark- and all-trans light-adapted states, as well upon isomerization to 13-cis in the M state. The C13-methyl group at the "business end" of the chromophore changes its orientation to the membrane upon photon absorption, moving towards W182 and thus driving the proton pump in energy conservation. Moreover, rhodopsin was studied as a prototype for G protein-coupled receptors (GPCRs) implicated in many biological responses in humans. In contrast to bR, the retinal chromophore of rhodopsin has an 11-cis conformation and is highly twisted in the dark state. Three sites of interaction affect the torsional deformation of retinal, viz. the protonated Schiff base with its carboxylate counterion; the C9-methyl group of the polyene; and the β-ionone ring within its hydrophobic pocket. For rhodopsin, the strain energy and dynamics of retinal as established by 2H NMR are implicated in substituent control of activation. Retinal is locked in a conformation that is twisted in the direction of the photoisomerization, which explains the dark stability of rhodopsin and allows for ultra-fast isomerization upon absorption of a photon. Torsional strain is relaxed in the meta I state that precedes subsequent receptor activation. Comparison of the two retinal proteins using solid-state 2H NMR is thus illuminating in terms of their different biological functions.
AB - Solid-state 2H NMR spectroscopy gives a powerful avenue to investigating the structures of ligands and cofactors bound to integral membrane proteins. For bacteriorhodopsin (bR) and rhodopsin, retinal was site-specifically labeled by deuteration of the methyl groups followed by regeneration of the apoprotein. 2H NMR studies of aligned membrane samples were conducted under conditions where rotational and translational diffusion of the protein were absent on the NMR time scale. The theoretical lineshape treatment involved a static axial distribution of rotating C-C2H3 groups about the local membrane frame, together with the static axial distribution of the local normal relative to the average normal. Simulation of solid-state 2H NMR lineshapes gave both the methyl group orientations and the alignment disorder (mosaic spread) of the membrane stack. The methyl bond orientations provided the angular restraints for structural analysis. In the case of bR the retinal chromophore is nearly planar in the dark- and all-trans light-adapted states, as well upon isomerization to 13-cis in the M state. The C13-methyl group at the "business end" of the chromophore changes its orientation to the membrane upon photon absorption, moving towards W182 and thus driving the proton pump in energy conservation. Moreover, rhodopsin was studied as a prototype for G protein-coupled receptors (GPCRs) implicated in many biological responses in humans. In contrast to bR, the retinal chromophore of rhodopsin has an 11-cis conformation and is highly twisted in the dark state. Three sites of interaction affect the torsional deformation of retinal, viz. the protonated Schiff base with its carboxylate counterion; the C9-methyl group of the polyene; and the β-ionone ring within its hydrophobic pocket. For rhodopsin, the strain energy and dynamics of retinal as established by 2H NMR are implicated in substituent control of activation. Retinal is locked in a conformation that is twisted in the direction of the photoisomerization, which explains the dark stability of rhodopsin and allows for ultra-fast isomerization upon absorption of a photon. Torsional strain is relaxed in the meta I state that precedes subsequent receptor activation. Comparison of the two retinal proteins using solid-state 2H NMR is thus illuminating in terms of their different biological functions.
KW - Bacteriorhodopsin
KW - G protein-coupled receptor
KW - Membrane
KW - Proton pump
KW - Retinal
KW - Rhodopsin
KW - Solid-state NMR
KW - Vision
UR - http://www.scopus.com/inward/record.url?scp=36849045169&partnerID=8YFLogxK
U2 - 10.1016/j.bbamem.2007.10.014
DO - 10.1016/j.bbamem.2007.10.014
M3 - Review article
C2 - 18021739
VL - 1768
SP - 2979
EP - 3000
JO - Biochimica et Biophysica Acta - Biomembranes
JF - Biochimica et Biophysica Acta - Biomembranes
SN - 0005-2736
IS - 12
ER -
ID: 5520891