Miscibility, chain packing, and hydration of 1-palmitoyl-2-oleoyl phosphatidylcholine and other lipids in surface phases.
Miscibility, chain packing, and hydration of 1-palmitoyl-2-oleoyl phosphatidylcholine and other lipids in surface phases.
复制标题
1-棕榈酰-2-油酰磷脂酰胆碱和其他脂质在表面相的混溶性、链堆积和水合。
DOI：
10.1016/s0006-3495(85)83828-5
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发表时间：
1985
影响因子：
3.4
通讯作者：
Brockman,HL
中科院分区：
文献类型：
--
作者：
Smaby,JM;Brockman,HL
研究了1-棕榈酰基-2-油酰基磷脂酰胆碱与三油酸酯、1，2-二油酸酯、1，3-二油酸酯、1(3)-单油酸酯、油醇、油酸甲酯、油酸和油氰酸酯(18：1脂)在Ar-水界面上的相容性。混合物在24℃时的等温相图由两个组成区域表征。在较低摩尔分数为18：1脂类的混合极限下，表面压力与组成无关，但在混合物特定的化学计量比以上，混合极限时的表面压力与组成有关。从二维相律可以看出，在低摩尔分数(18：1)的脂类表面，表面由磷脂和磷脂与18：1脂类的优先堆积排列或络合物组成，而在络合物的化学计量比以上，表面相由络合物和过量的18：1脂类组成。在相图的两个区域中，沿相边界的混合显然是理想的，从而允许应用先前描述的状态方程(J.M.Smaby和H.L.Brockman，1984，生物化学，23：3312-3316)。通过这种分析，获得了磷脂、络合物和18：1脂类的表观部分分子面积和水合作用。对络合态和非络合态的这些计算参数的比较表明，脂肪族部分的行为与极性头基团无关。每个18：1链向络合状态的转变包括大约一个界面水分子及其相应的面积的损失。对于含有一条以上链的18：1脂类，另一条链上的另外两个水分子同时存在于两种状态，但对分子面积的贡献很小。
The miscibility of 1-palmitoyl-2-oleoyl phosphatidylcholine with triolein, 1,2-diolein, 1,3-diolein, 1(3)-monoolein, oleyl alcohol, methyl oleate, oleic acid, and oleyl cyanide (18:1 lipids) was studied at the argon-water interface. The isothermal phase diagrams for the mixtures at 24 degrees were characterized by two compositional regions. At the limit of miscibility with lower mol fractions of 18:1 lipid, the surface pressure was composition-independent, but above a mixture-specific stoichiometry, surface pressure at the limit of miscibility was composition-dependent. From the two-dimensional phase rule, it was determined that at low mol fractions of 18:1 lipids, the surface consisted of phospholipid and a preferred packing array or complex of phospholipid and 18:1 lipid, whereas, above the stoichiometry of the complex, the surface phase consisted of complex and excess 18:1 lipids. In both regions of the phase diagram, mixing along the phase boundary was apparently ideal allowing application of an equation of state described earlier (J. M. Smaby and H. L. Brockman, 1984, Biochemistry, 23:3312–3316). From such analysis, apparent partial molecular areas and hydrations for phospholipid, complex, and 18:1 lipid were obtained. Comparison of these calculated parameters for the complexed and uncomplexed states shows that the aliphatic moieties behave independently of polar head group. The transition of each 18:1 chain to the complexed state involves the loss of about one interfacial water molecule and its corresponding area. For 18:1 lipids with more than one chain another two water molecules per additional chain are present in both states but contribute little to molecular area.(ABSTRACT TRUNCATED AT 250 WORDS)