Enantioselective binding of an 11-cis-locked cyclopropyl retinal. The conformation of retinal in bovine rhodopsin.
نویسندگان
چکیده
[formula: see text] The conformation of the retinal chromophore in rhodopsin is central for understanding the visual transduction process. The absolute twist around the 12-s bond of the chromophore in rhodopsin has been determined by studies with 11-cis-locked 11,12-cyclopropylretinal analogues (11S,12R)-2 and (11R,12S)-3, enantioselectively synthesized with the aid of an enzyme. The finding that enantiomer 2 binds to opsin while the other 3 does not defines the absolute sense of twist around the 12-s bond.
منابع مشابه
Solution and biologically relevant conformations of enantiomeric 11-cis-locked cyclopropyl retinals.
To gain information on the conformation of the 11-cis-retinylidene chromophore bound to bovine opsin, the enantiomeric pair (2a and 2b) of 11-cis-locked bicyclo[5.1.0]octyl retinal (retCPr) 2 was prepared and its conformation was investigated by NMR, geometry optimization, and CD calculations. This compound is also of interest since it contains a unique moiety in which a chiral cyclopropyl grou...
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عنوان ژورنال:
- Organic letters
دوره 1 1 شماره
صفحات -
تاریخ انتشار 1999