Details

Autor(en) / Beteiligte

• Carravetta, Marina
• Zhao, Xin
• Johannessen, Ole G
• Lai, Wai Cheu
• Verhoeven, Michiel A
• Bovee-Geurts, Petra H. M
• Verdegem, Peter J. E
• Kiihne, Suzanne
• Luthman, Henrik
• de Groot, Huub J. M
• deGrip, Willem J
• Lugtenburg, Johan
• Levitt, Malcolm H

Titel

Protein-Induced Bonding Perturbation of the Rhodopsin Chromophore Detected by Double-Quantum Solid-State NMR

Ist Teil von

• Journal of the American Chemical Society, 2004-03, Vol.126 (12), p.3948-3953

Ort / Verlag

Washington, DC: American Chemical Society

Erscheinungsjahr

2004

Quelle

MEDLINE

Beschreibungen/Notizen

• We have obtained carbon−carbon bond length data for the functional retinylidene chromophore of rhodopsin, with a spatial resolution of 3 pm. The very high resolution was obtained by performing double-quantum solid-state NMR on a set of noncrystalline isotopically labelled bovine rhodopsin samples. We detected localized perturbations of the carbon−carbon bond lengths of the retinylidene chromophore. The observations are consistent with a model in which the positive charge of the protonated Schiff base penetrates into the polyene chain and partially concentrates around the C13 position. This coincides with the proximity of a water molecule located between the glutamate-181 and serine-186 residues of the second extracellular loop, which is folded back into the transmembrane region. These measurements support the hypothesis that the polar residues of the second extracellular loop and the associated water molecule assist the rapid selective photoisomerization of the retinylidene chromophore by stabilizing a partial positive charge in the center of the polyene chain.