Determination of a molecular torsional angle in the metarhodopsin-I photointermediate of rhodopsin by double-quantum solid-state NMR.
J Biomol NMR
; 16(1): 1-8, 2000 Jan.
Article
em En
| MEDLINE
| ID: mdl-10718607
ABSTRACT
We present a solid-state NMR study of metarhodopsin-1, the pre-discharge intermediate of the photochemical signal transduction cascade of rhodopsin, which is the 41 kDa integral membrane protein that triggers phototransduction in vertebrate rod cells. The H-C10-C11-H torsional angles of the retinylidene chromophore in bovine rhodopsin and metarhodopsin-I were determined simultaneously in the photo-activated membrane-bound state, using double-quantum heteronuclear local field spectroscopy. The torsional angles were estimated to be [phi] = 160+/-10 degrees for rhodopsin and phi = 180+/-25 degrees for metarhodopsin-I. The result is consistent with current models of the photo-induced conformational transitions in the chromophore, in which the 11-Z retinal ground state is twisted, while the later photointermediates have a planar all-E conformation.
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Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Rodopsina
Limite:
Animals
Idioma:
En
Ano de publicação:
2000
Tipo de documento:
Article