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Carotenoid isomerase: a tale of light and isomers
Abstract:
Carotenoids are terpenoid pigments containing systems of conjugated double bonds, each of which can exist in a cis or trans configuration. The existence of a carotenoid isomerase (CrtISO) mediating cis-to-trans isomerization has been suspected ever since the description of the tomato tangerine mutant in the early 1940s, whose fruits accumulate a poly-cis-isomer of lycopene. Recently, CrtISO has been cloned in Synechocystis and in plants, and has been shown to be related to bacterial carotene desaturases.
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