FUSION OF LIPID BILAYERS - A MODEL INVOLVING MECHANISTIC CONNECTION TO HII-PHASE FORMING LIPIDS
FUSION OF LIPID BILAYERS - A MODEL INVOLVING MECHANISTIC CONNECTION TO HII-PHASE FORMING LIPIDS
复制标题
DOI：
10.1016/0009-3084(92)90041-m
复制
发表时间：
1992-12-01
影响因子：
3.4
通讯作者：
KINNUNEN, PKJ
中科院分区：
文献类型：
--
作者：
KINNUNEN, PKJ
描述了脂质双分子层融合的分子机制模型。该模型的一个关键特征与层状->六方H（II）相转变有关，是一种新的假设的脂质构象，这里暂定称为扩展构象。在融合过程中，这种构象可以在两个靠近的囊泡之间的接触部位表现出来，并涉及磷脂分子的酰基链向相反方向延伸，即嵌入两个相反的双层中，同时保持界面中的头基团。尽管证明磷脂存在延伸构象的证据很少，但这种构象似乎与目前可用的实验数据相一致。同样重要的是，延伸的构象允许两个双层膜的融合，以最小的脂质烃链暴露于水。它还可以解释膜融合的其他特征，如脂质在中间状态下混合而不混合囊泡内容物，以及融合性脂质作用的分子基础。
A model for the molecular mechanism of the fusion of lipid bilayers is described. A crucial feature of this model and related to the lamellar --> hexagonal phase H(II) transition is a novel, hypothetical lipid conformation, tentatively referred to here as extended. During fusion this conformation could manifest itself in the contact site between two vesicles in close proximity and involves the extension of the acyl chains of a phospholipid molecule in opposite directions, i.e. embedded into the two opposing bilayers while maintaining the headgroup in the interface. Although evidence for the occurrence of the extended conformation for phospholipids is sparse this conformation appears to be compatible with currently available experimental data. Of importance also is that the extended conformation allows for the fusion of two bilayer membranes to proceed with minimal exposure of the lipid hydrocarbon chains to water. It can also account for other features of membrane fusion such as lipid mixing in the intermediate state without mixing of the vesicle contents as well as for the molecular basis of the action of fusogenic lipids.