通过单分子膜研究和荧光显微镜观察法研究脂磷壁酸在二棕榈酰磷脂酰胆碱中的混溶性。

Miscibility of lipoteichoic acid in dipalmitoylphosphatidylcholine studied by monofilm investigations and fluorescence microscopy.

作者信息

Gutberlet T, Milde K, Bradaczek H, Haas H, Möhwald H

机构信息

Institut für Kristallographie der Freien Universität Berlin, Germany.

出版信息

Chem Phys Lipids. 1994 Feb;69(2):151-9. doi: 10.1016/0009-3084(94)90036-1.

DOI:10.1016/0009-3084(94)90036-1

PMID:8181104

Abstract

The miscibility of the bacterial amphiphile lipoteichoic acid, a constituent of the cytoplasmic membrane of Gram-positive bacteria, in dipalmitoylphosphatidylcholine has been investigated by classic monofilm measurements and fluorescence microscopy at the air-water interface of monofilms obtained by spreading mixtures of both amphiphiles on a water subphase. The isotherms indicated miscibility of both lipids at concentrations up to 30 mol% lipoteichoic acid, whereas at higher concentrations immiscibility was detected. Increasing the lateral pressure over a certain value, lipoteichoic acid is squeezed out of the monofilm. By fluorescence microscopy the influence of lipoteichoic acid on the domain shape of condensed dipalmitoylphosphatidylcholine phases has been studied. The balance between hydrophobic and hydrophilic forces in the mixtures of both amphiphiles is discussed.

摘要

革兰氏阳性菌细胞质膜的组成成分——细菌两亲性脂磷壁酸与二棕榈酰磷脂酰胆碱在气-水界面单分子膜中的混溶性，已通过经典单分子膜测量法和荧光显微镜进行了研究。该单分子膜是通过将两种两亲性物质的混合物铺展在水亚相上获得的。等温线表明，在脂磷壁酸浓度高达30 mol%时，两种脂质是混溶的，而在更高浓度时则检测到不混溶。当侧向压力增加到一定值以上时，脂磷壁酸会被挤出单分子膜。通过荧光显微镜研究了脂磷壁酸对凝聚态二棕榈酰磷脂酰胆碱相的畴形状的影响。讨论了两种两亲性物质混合物中疏水作用力和亲水作用力之间的平衡。