Synthesis of isotopically labelled retinal. Structural and functional studies at the atomic level of the chromophore in visual pigments.
OBJECTIVE
To describe the strategy followed in studying the structure and function of the chromophore in visual pigments at the atomic level.


METHODS
A three-step strategy was followed. First, 11-cis retinal with high enrichment (99% 13C or 99% 2H) at pre-determined positions or combinations of positions was synthesized. Second, the rhodopsins with isotope label in the chromophore were prepared combining opsin with the isotopically labelled 11-cis retinal. Third, these systems were studied with isotope-sensitive physical techniques.


CONCLUSIONS
Isotope labelling together with isotope-sensitive spectroscopy is a highly promising method for obtaining information at the atomic level of biologically active systems. Strategies based on specific stable isotope labelling are likely to be applicable to many research areas.
Lugtenburg
J
J
Leiden University, Leiden Institute of Chemical Research, Gorlaeus Laboratories, Netherlands.
D002247:Carbon Isotopes; D003903:Deuterium; D007553:Isotope Labeling; D009682:Magnetic Resonance Spectroscopy; D012168:Retinal Pigments / Q000737:chemistry*; D012172:Retinaldehyde / Q000138:chemical synthesis* / Q000502:physiology*; D013329:Structure-Activity Relationship
D002247:Carbon Isotopes; D012168:Retinal Pigments; D003903:Deuterium; D012172:Retinaldehyde