Ono S, Kato T, Lee S, Aoyagi H, Ohno M
Department of Chemistry, Faculty of Science, Kyushu University, Fukuoka, Japan.
J Chromatogr. 1992 Apr 24;597(1-2):293-7. doi: 10.1016/0021-9673(92)80123-c.
In order to investigate the conformation and localization of lipopeptides in lipid bilayers, a basic model peptide with a long alkyl chain, Ac-Ser-Val-Lys-Amy-Ser-Trp-Lys-Val-NHCH3 Amy-1; Amy = alpha-aminomyristic acid) was synthesized. Its interaction with neutral and acidic phospholipid bilayers was studied by circular dichroism (CD) spectroscopy, dye leakage and fluorescence measurements. Another peptide, Ac-Leu-Ala-Arg-Leu-Trp-Amy-Arg-Leu-Leu-Ala-Arg-Leu-NHCH3 (Amy-2), which was prepared previously, was used for comparison. The CD data indicated that Amy-1 took a beta-turn and/or a beta-structure in the absence and presence of liposomes. Amy-2 formed a beta-structure in aqueous solution and an alpha-helical structure in liposomes. The dye leakage ability of Amy-1 was much weaker than that of Amy-2. Fluorescence spectroscopic data suggest that the peptides are immersed in lipid bilayers. Based on these results, discussion is made in terms of localization of the peptides in lipid bilayers.
为了研究脂肽在脂质双层中的构象和定位，合成了一种带有长烷基链的碱性模型肽，即Ac-Ser-Val-Lys-Amy-Ser-Trp-Lys-Val-NHCH3 Amy-1（Amy = α-氨基肉豆蔻酸）。通过圆二色性（CD）光谱、染料泄漏和荧光测量研究了其与中性和酸性磷脂双层的相互作用。另一种先前制备的肽Ac-Leu-Ala-Arg-Leu-Trp-Amy-Arg-Leu-Leu-Ala-Arg-Leu-NHCH3（Amy-2）用于比较。CD数据表明，在不存在和存在脂质体的情况下，Amy-1呈现β-转角和/或β-结构。Amy-2在水溶液中形成β-结构，在脂质体中形成α-螺旋结构。Amy-1的染料泄漏能力比Amy-2弱得多。荧光光谱数据表明这些肽嵌入脂质双层中。基于这些结果，对肽在脂质双层中的定位进行了讨论。
