Photochemistry of monomethylated and permethylated bacteriorhodopsin.
Biophys J
; 54(3): 557-62, 1988 Sep.
Article
em En
| MEDLINE
| ID: mdl-3207841
ABSTRACT
Methylation of the nonactive site lysines of bacteriorhodopsin to form permethylated bacteriorhodopsin does not interfere with the formation of the short wavelength intermediate M412 or light-induced proton release/uptake. The absorption spectrum is similar to that of the native bacteriorhodopsin. However, additional monomethylation of the active site lysine of bacteriorhodopsin causes a red shift of the absorption maximum from 568 nm in light-adapted bacteriorhodopsin [BR] to 630 nm. The photochemistry of active-site methylated BR does not proceed beyond the L-photointermediate. In particular, the photointermediate corresponding to M412 does not form, and there is no proton pumping. Moreover, there is no tyrosine deprotonation. Thus, the formation of an M-type photointermediate is required for proton pumping by BR.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Bacteriorodopsinas
Idioma:
En
Revista:
Biophys J
Ano de publicação:
1988
Tipo de documento:
Article