由饱和磷脂酰胆碱和磷脂酰甘油混合物组成的大型多层囊泡的自发成泡。

Spontaneous vesiculation of large multilamellar vesicles composed of saturated phosphatidylcholine and phosphatidylglycerol mixtures.

作者信息

Madden T D, Tilcock C P, Wong K, Cullis P R

机构信息

Department of Biochemistry, University of British Columbia, Vancouver, Canada.

出版信息

Biochemistry. 1988 Nov 29;27(24):8724-30. doi: 10.1021/bi00424a006.

DOI:10.1021/bi00424a006

PMID:3242602

Abstract

The influence of temperature and ionic strength on the vesiculation properties of large multilamellar vesicles containing various proportions of dimyristoylphosphatidylglycerol has been investigated. It is shown that at low ionic strengths preformed large multilamellar vesicles composed of dimyristoylphosphatidylcholine and dimyristoylphosphatidylglycerol (7:3) on incubation at the gel to liquid-crystalline transition temperature (Tc approximately 23 degrees C) spontaneously vesiculate to form predominantly unilamellar systems with a mean diameter of 120 nm. Such vesiculation is not observed for incubations at temperatures appreciably above or below Tc, and is also inhibited by higher ionic strengths. Stable large multilamellar vesicles are formed, however, in systems containing the dioleoyl species of phosphatidylcholine or phosphatidylglycerol and also for dimyristoylphosphatidylcholine/dimyristoylphosphatidylserine mixtures. The vesiculation properties of dimyristoylphosphatidylcholine/dimyristoylphosphatidylglycerol mixtures, therefore, appear to reflect an instability in the region of the Tc driven by surface potential effects which are specific for the glycerol headgroup.

摘要

研究了温度和离子强度对含有不同比例二肉豆蔻酰磷脂酰甘油的大多层囊泡囊泡化性质的影响。结果表明，在低离子强度下，由二肉豆蔻酰磷脂酰胆碱和二肉豆蔻酰磷脂酰甘油（7:3）组成的预先形成的大多层囊泡在凝胶态到液晶态转变温度（Tc约为23℃）下孵育时，会自发囊泡化形成主要为平均直径120nm的单层体系。在明显高于或低于Tc的温度下孵育时未观察到这种囊泡化现象，并且较高的离子强度也会抑制这种现象。然而，在含有二油酰基磷脂酰胆碱或磷脂酰甘油的体系中以及二肉豆蔻酰磷脂酰胆碱/二肉豆蔻酰磷脂酰丝氨酸混合物中会形成稳定的大多层囊泡。因此，二肉豆蔻酰磷脂酰胆碱/二肉豆蔻酰磷脂酰甘油混合物的囊泡化性质似乎反映了由甘油头部基团特有的表面电位效应驱动的Tc区域的不稳定性。