Models for bacteriorhodopsin-catalyzed dark cis-trans isomerization of bound retinal
- Brookhaven National Laboratory, Upton, NY (USA)
The syntheses of syn- and anti-2-aza-6-carboxymethylbicyclo(2.2.2)octane and syn and anti-2-aza-6-carboxypropyl(2.2.2)octane zwitterions are described. These compounds, which have secondary amines to form positively charged Schiff bases with retinal and a pendant carboxylate anion to interact with the polyeniminium system, mimic the presence of aspartate-212 and lysine-216 at the retinal binding/cis-trans isomerization site of bacteriorhodopsin. Kinetics of retinal cis-trans isomerization of these model compounds are reported and are discussed in light of previous MNDO calculations (J. Am. Chem. Soc. 1987, 109, 1627-1631) of isomerization barrier heights affected by the movement of an anion to different positions with respect to the polyeniminium system.
- DOE Contract Number:
- AC02-76CH00016
- OSTI ID:
- 6649597
- Journal Information:
- Journal of the American Chemical Society; (USA), Journal Name: Journal of the American Chemical Society; (USA) Vol. 112:11; ISSN 0002-7863; ISSN JACSA
- Country of Publication:
- United States
- Language:
- English
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