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Publication Abstract from PubMed
Enzymes that produce retinal and related apocarotenoids constitute a sequence- and thus structure-related family, a member of which was analyzed by x-ray diffraction. This member is an oxygenase and contains an Fe2+-4-His arrangement at the axis of a seven-bladed beta-propeller chain fold covered by a dome formed by six large loops. The Fe2+ is accessible through a long nonpolar tunnel that holds a carotenoid derivative in one of the crystals. On binding, three consecutive double bonds of this carotenoid changed from a straight all-trans to a cranked cis-trans-cis conformation. The remaining trans bond is located at the dioxygen-ligated Fe2+ and cleaved by oxygen.
The structure of a retinal-forming carotenoid oxygenase.,Kloer DP, Ruch S, Al-Babili S, Beyer P, Schulz GE Science. 2005 Apr 8;308(5719):267-9. PMID:15821095[1]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
References
↑ Kloer DP, Ruch S, Al-Babili S, Beyer P, Schulz GE. The structure of a retinal-forming carotenoid oxygenase. Science. 2005 Apr 8;308(5719):267-9. PMID:15821095 doi:308/5719/267