LIPOSOME FUSION CATALYTICALLY INDUCED BY PHOSPHOLIPASE-C
LIPOSOME FUSION CATALYTICALLY INDUCED BY PHOSPHOLIPASE-C
复制标题
DOI：
10.1021/bi00444a032
复制
发表时间：
1989-09-05
期刊：
影响因子：
2.9
通讯作者：
ALONSO, A
中科院分区：
文献类型：
--
作者：
NIEVA, JL;GONI, FM;ALONSO, A
磷脂酶c处理由磷脂酰胆碱/磷脂酰乙醇胺/胆固醇（50:25:25摩尔比）组成的大单层囊泡。磷脂裂解的早期阶段伴随着双层脂质的混合（通过十八烷基罗丹明荧光脱猝监测）和囊泡内容物的无泄漏混合[使用8-氨基萘-1,3,6-三磺酸（ANTS）和对二甲苯（溴化吡啶）（DPX）测量]。这些结果是根据磷脂酶c的催化活性诱导的囊泡融合来解释的。使用超声处理的单层囊泡减少了滞后时间，但没有改变融合过程的幅度。磷脂酰乙醇胺和胆固醇的存在似乎是在低水平磷脂水解时发生可测量的融合效应所必需的。最佳融合率观察到大约10-20个酶分子每大单层囊泡。这种催化诱导的脂质体输注系统可能与解释生理膜融合过程有关。
Large unilamellar vesicles composed of phosphatidylcholine/phosphatidylethanolamine/cholesterol (50:25:25 mole ratio) were treated with phospholipase C. The early stages of phospholipid cleavage are accompanied by mixing of bilayer lipids (monitored by dequenching of octadecylrhodamine fluorescence) and leakage-free mixing of vesicle contents [measured by using 8-aminonaphthalene-1,3,6-trisulfonic acid (ANTS) and p-xylylenbis(pyridinium bromide) (DPX)]. These results are interpreted in terms of vesicle fusion induced by the catalytic activity of phospholipase C. The use of sonicated unilamellar vesicles decreases the lag time, but does not modifly the amplitude, of the fusion process. The presence of both phosphatidylethanolamine and cholesterol appears to be essential for measurable fusion effects to occur with low levels of phospholipid hydrolysis. Optimal fusion rates are observed with about 10-20 enzyme molecules per large unilamellar vesicle. This system of catalytically induced liposome infusion may be of relevance for the interpretation of physiological membrane fusion processes.