Conformation of the polar headgroup of sphingomyelin and its analogues.
Conformation of the polar headgroup of sphingomyelin and its analogues.
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DOI：
10.1016/0005-2736(88)90076-4
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发表时间：
1988-04
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影响因子：
--
通讯作者：
K. Bruzik
中科院分区：
文献类型：
--
作者：
K. Bruzik
用高分辨核磁共振波谱详细研究了人工合成的赤硬脂酰鞘磷脂(1)及其1-苏氨酸异构体(2)和1(3和4)的硫代类似物的极性头基的构象。在单体和聚集态，1的磷胆碱功能采用向斜构象(α5扭转角)，类似于磷脂酰胆碱(Hauser，H.，Guyer，W.，Pascher，I.，Skrabal，P.和Sundell，S.(1980年)生化19,366-373)。鞘氨醇主链的C1--C2键(θ1角)的构象主要是向斜的，类似于结晶的半乳糖脑苷的构象(Pascher，I.和Sundell，S.(1977)Chem.太棒了。脂类20、175-191)。相反，l-苏氨酸异构体在C1C2键附近表现出不受限制的旋转。讨论了导致1和2不同构象的3-羟基官能团和鞘氨醇的桥式氧原子之间存在氢键的可能性。用硫修饰1中的磷酸基官能团对所得类似物的构象没有显著影响。所研究的所有化合物的C--O-磷酸酯键(α1和α4扭转角)的构象主要是反周面构象。与其他双链磷脂类似，鞘磷脂显示出对C2C3键的反平面构象的偏好。
The conformation of the polar headgroup of syntheticd-erythro-stearoylsphingomyelin (1), itsl-threo-isomer (2) and phosphorothioyl analogues of 1 (3 and 4) has been studied in detail by high-resolution NMR spectroscopy. In both monomeric and aggregated states the phosphocholine function of 1 adopts the synclinal conformation (α5torsional angle), in analogy with phosphatidylcholine (Hauser, H., Guyer, W., Pascher, I ., Skrabal, P. and Sundell, S. (1980) Biochemistry 19, 366–373). The conformation about the C1C2 bond (θ1angle) of the sphingosine backbone is predominantly —synclinal, analogously to the conformation of the crystalline galactosyl cerebroside (Pascher, I. and Sundell, S. (1977) Chem. Phys. Lipids 20, 175–191). In contrast, thel-threo-isomer displays unrestricted rotation about C1C2 bond. The possibility of the existence of a hydrogen bond between the 3-hydroxyl function and the bridged oxygen atom of sphingosine responsible for the different conformation of 1 and 2 is discussed. The modification of the phosphate function in 1 with sulfur has no significant effect on the conformation of the resulting analogues. The conformation of all studied compounds about the CO phosphoester bonds (α1and α4torsion angles) is mainly antiperiplanar. Similar to other double-chain phospholipids, sphingomyelin shows a preference towards the antiperiplanar conformation about the C2C3 bond.