BINDING AFFINITIES OF RETINOL AND RELATED COMPOUNDS TO RETINOL BINDING-PROTEINS
BINDING AFFINITIES OF RETINOL AND RELATED COMPOUNDS TO RETINOL BINDING-PROTEINS
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DOI：
10.1111/j.1432-1033.1976.tb10390.x
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发表时间：
1976-01-01
期刊：
影响因子：
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通讯作者：
SHINITZKY, M
中科院分区：
文献类型：
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作者：
COGAN, U;KOPELMAN, M;SHINITZKY, M
用荧光滴定测定了表观离解常数。视黄醇、视黄酸、视黄乙酸酯和视黄酸棕榈酸酯的全反式异构体中，人-视黄醇结合蛋白和鸡-视黄醇结合蛋白。利用视黄醇和视黄酸乙酯与蛋白质结合时的荧光增强来确定这些化合物的结合亲和力。对于本质上是一种非荧光化合物的维甲酸，由于色氨酸残基向结合配体传递能量而使蛋白质荧光猝灭，从而决定了结合亲和力。不同的配体与这两种类型的视黄醇结合蛋白表现出1：1的分子络合物。视黄醇、视黄酸和视黄乙酸酯对两种载体蛋白具有相似的结合亲和力。视黄醇，**图形**。=1.9倍。10-7M，含人视黄醇结合蛋白和**图形**。=1.5倍。10-7M，含鸡肉-视黄醇结合蛋白；用于维甲酸。**图表**。=2.1倍。10-7M，含人视黄醇结合蛋白和**图形**。=2.2倍。10-7M含有鸡肉-视黄醇结合蛋白；用于视黄酸乙酯。**图表**。=2.2倍。10-7M，含人视黄醇结合蛋白和**图形**。=1.7倍。10-7M，鸡-视黄醇结合蛋白。视黄酸棕榈酸酯似乎与两种视黄醇结合蛋白中的任何一种都有弱的结合，如果真的有的话。人和鸡视黄醇结合蛋白在配体结合方面的行为相似。非极性相互作用可能在结合中起主要作用，官能团和电荷的影响是次要的。
Fluorimetric titrations were used to determine apparent dissociation constants .**GRAPHIC**. of the all-trans isomers of retinol, retinoic acid, retinyl acetate and retinyl palmitate to human-retinol binding protein and chicken-retinol binding protein. Enhancement of the fluorescence of retinol and retinyl acetate when bound to the protein was utilized to establish the binding affinity of these compounds. With retinoic acid which is essentially a non-fluorescent compound, quenching of protein fluorescence due to energy transfer to the bound ligand from tryptophanyl residues served to determine the binding affinity. The various ligands display 1:1 molecular complexes with both types of retinol binding proteins. Retinol, retinoic acid and retinyl acetate had similar binding affinities to both species of carrier proteins. For retinol, .**GRAPHIC**. = 1.9 .times. 10-7 M with human-retinol binding protein and .**GRAPHIC**. = 1.5 .times. 10-7 M with chicken-retinol binding protein; for retinoic acid .**GRAPHIC**. = 2.1 .times. 10-7 M with human-retinol binding protein and .**GRAPHIC**. = 2.2 .times. 10-7 M with chicken-retinol binding protein; for retinyl acetate .**GRAPHIC**. = 2.2 .times. 10-7 M with human-retinol binding protein and .**GRAPHIC**. = 1.7 .times. 10-7 M with chicken-retinol binding protein. Retinyl palmitate appeared to have weak association with either of the 2 retinol binding proteins, if at all. Both human and chicken retinol binding proteins behave similarly with respect to the binding of the ligands. Non-polar interactions probably play a primary role in the binding and effects of functional groups and charges are of secondary importance.