Handa T, Komatsu H, Kakee A, Miyajima K
Faculty of Pharmaceutical Sciences, Kyoto University, Japan.
Chem Pharm Bull (Tokyo). 1990 Aug;38(8):2079-82. doi: 10.1248/cpb.38.2079.
Cosonication of egg yolk lecithin and triolein with apolipoproteins isolated from pig high density lipoprotein (apoHDL) gave us reconstituted high density lipoprotein particles (r-HDLs) of 9 nm in average diameter. They were smaller than microemulsion particles (MEs) composed of the lipids (35 nm). The protein/egg yolk lecithin ratio in the fractionated r-HDLs was higher in the smaller particles. Binding of a hydrophobic probe, 2-p-toluidinylnaphthalene-6-sulfonate (TNS), to MEs, r-HDLs and apoHDL were evaluated on the basis of Halfman and Nishida's method. The reconstitution of apoHDL into MEs led to a 68% reduction in the binding of TNS and a small increase in the alpha-helix content as compared with free apoHDL. The binding experiments also showed the condensation of lecithin molecules at the r-HDL surface. The amphipathic helixes of apoHDL are located in the surface monolayer of egg yolk lecithin surrounding the triolein core. The intercalation of the hydrophobic residues of apoHDL between egg yolk lecithin molecules brings about a pronounced curvature of the surface and a decrease in the particle diameter.
将蛋黄卵磷脂和三油酸甘油酯与从猪高密度脂蛋白（apoHDL）中分离出的载脂蛋白进行共超声处理，得到了平均直径为9纳米的重组高密度脂蛋白颗粒（r-HDLs）。它们比由这些脂质组成的微乳液颗粒（MEs，直径35纳米）更小。分级分离的r-HDLs中较小颗粒的蛋白质/蛋黄卵磷脂比例更高。基于Halfman和Nishida的方法评估了疏水性探针2-对甲苯胺基萘-6-磺酸盐（TNS）与MEs、r-HDLs和apoHDL的结合情况。与游离apoHDL相比，apoHDL重组到MEs中导致TNS结合减少68%，α-螺旋含量略有增加。结合实验还表明卵磷脂分子在r-HDL表面发生了凝聚。apoHDL的两亲性螺旋位于围绕三油酸甘油酯核心的蛋黄卵磷脂表面单层中。apoHDL的疏水残基插入蛋黄卵磷脂分子之间导致表面明显弯曲，颗粒直径减小。
