Multiple membrane interactions and versatile vesicle deformations elicited by melittin.
Multiple membrane interactions and versatile vesicle deformations elicited by melittin.
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DOI：
10.3390/toxins5040637
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发表时间：
2013-04-17
期刊：
影响因子：
4.2
通讯作者：
Takiguchi K
中科院分区：
文献类型：
--
作者：
Takahashi T;Nomura F;Yokoyama Y;Tanaka-Takiguchi Y;Homma M;Takiguchi K
蜂毒肽可诱导膜中的各种反应，并作为膜相互作用肽的模型得到了广泛研究；然而，蜂毒素产生作用的机制仍不清楚。在这里，我们使用暗场光学显微镜直接实时成像观察了蜂毒肽诱导的单个巨型脂质体的变化，并且所涉及的机制与使用圆二色性、共沉降、色氨酸残基荧光猝灭和电子显微镜获得的结果相关。根据膜中带负电的磷脂的浓度以及脂质和蜂毒肽之间的分子比，蜂毒肽诱导脂质体的“膜面积增加”、“阶段性收缩”或“溶解”。在分阶段收缩中，脂质体在其表面形成小颗粒并迅速减小尺寸。在主要观察到膜面积增加、阶段性收缩或溶解的条件下，蜂毒肽的二级结构主要分别被估计为α-螺旋、β-样或无序结构。当膜面积增加或发生阶段性收缩时，几乎所有蜂毒肽都与膜结合，并到达膜的比溶解发生时更多的疏水区域。这些结果表明，蜂毒肽的各种作用源于其根据条件采用各种结构和膜结合状态的能力。
Melittin induces various reactions in membranes and has been widely studied as a model for membrane-interacting peptide; however, the mechanism whereby melittin elicits its effects remains unclear. Here, we observed melittin-induced changes in individual giant liposomes using direct real-time imaging by dark-field optical microscopy, and the mechanisms involved were correlated with results obtained using circular dichroism, cosedimentation, fluorescence quenching of tryptophan residues, and electron microscopy. Depending on the concentration of negatively charged phospholipids in the membrane and the molecular ratio between lipid and melittin, melittin induced the “increasing membrane area”, “phased shrinkage”, or “solubilization” of liposomes. In phased shrinkage, liposomes formed small particles on their surface and rapidly decreased in size. Under conditions in which the increasing membrane area, phased shrinkage, or solubilization were mainly observed, the secondary structure of melittin was primarily estimated as an α-helix, β-like, or disordered structure, respectively. When the increasing membrane area or phased shrinkage occurred, almost all melittin was bound to the membranes and reached more hydrophobic regions of the membranes than when solubilization occurred. These results indicate that the various effects of melittin result from its ability to adopt various structures and membrane-binding states depending on the conditions.
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影响因子：
2.4
作者：
Fernandez-Vidal, Monica;White, Stephen H.;Ladokhin, Alexey S.
通讯作者：
Ladokhin, Alexey S.
影响因子：
56.9
作者：
HABERMAN.E
通讯作者：
HABERMAN.E
DOI：
10.1016/0005-2736(83)90473-x
发表时间：
1983-01-01
期刊：
BIOCHIMICA ET BIOPHYSICA ACTA
影响因子：
--
作者：
HIDER, RC;KHADER, F;TATHAM, AS
通讯作者：
TATHAM, AS
DOI：
10.1016/0167-4838(90)90131-x
发表时间：
1990-09-27
期刊：
BIOCHIMICA ET BIOPHYSICA ACTA
影响因子：
--
作者：
KASZYCKI, P;WASYLEWSKI, Z
通讯作者：
WASYLEWSKI, Z
影响因子：
2.9
作者：
ALTENBACH, C;HUBBELL, WL
通讯作者：
HUBBELL, WL