Carotenoid—protein Complexes
نویسنده
چکیده
A survey of carotenoid—protein complexes is presented. Distinction is made between astaxanthin—proteins in which the absorption band of the carotenoid is unaltered in shape, and carotenoid—lipoglycoprotein complexes. The proposal by Buchwald and Jencks79 that the carotenoid is twisted about the double bonds of the polyene chain, is discussed and sustained for astaxanthin—proteins. A mode of binding for the carotenoid in these complexes is proposed, involving hydrogen—bonding of keto groups of the polyene to imide groups of peptide bonds of the apoprotein.
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