Ca2+ and pH induced fusion of small unilamellar vesicles consisting of phosphatidylethanolamine and negatively charged phospholipids: a freeze fracture study.
Ca2+ and pH induced fusion of small unilamellar vesicles consisting of phosphatidylethanolamine and negatively charged phospholipids: a freeze fracture study.
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Ca2 和 pH 诱导由磷脂酰乙醇胺和带负电的磷脂组成的小单层囊泡融合：冷冻断裂研究。
DOI：
10.1016/0006-291x(83)91253-6
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发表时间：
1983
影响因子：
3.1
通讯作者：
P. Cullis
中科院分区：
文献类型：
--
作者：
M. Hope;D. Walker;P. Cullis
用冷冻断裂技术研究了由80摩尔%不饱和磷脂酰乙醇胺和20摩尔%磷脂酰丝氨酸、磷脂酰肌醇、磷脂酸或心磷脂组成的小（超声）单层囊泡（SUV）系统的融合过程。所有这些混合物都具有Ca2+的特性，在某些情况下，低pH值可以在这些脂质混合物的大多层分散中触发双层到六方（HII）相变。研究表明，当SUV系统受到类似的协议时，囊泡首先融合形成更大的系统，而不是hii相形成，这种融合伴随着脂质颗粒结构的出现，通常定位于融合界面。我们得出结论，促进hii相结构的因素最初导致单层体系的融合，这种融合通过中间形成非层状，可能是倒立的胶束结构进行。
Fusion processes in small (sonicated) unilamellar vesicle (SUV) systems composed of 80 mol % unsaturated phosphatidylethanolamine and 20 mol % of phosphatidylserine, phosphatidylinositol, phosphatidic acid or cardiolipin have been examined by freeze-fracture techniques. All these mixtures have the property that Ca2+and, in some cases low pH, can trigger bilayer to hexagonal (HII) phase transitions in large multilamellar dispersions of these lipid mixtures. It is shown that when the SUV systems are subjected to similar protocols, the vesicles first fuse to form larger systems prior to HIIphase formation and this fusion is accompanied by the appearance of lipidic particle structures, often localized to the fusion interface. We conclude that factors promoting HIIphase structure initially result in fusion of unilamellar systems and that this fusion proceeds via intermediary formation of non-lamellar, possibly inverted micellar, structure.