Interaction of poly-L-arginine with dihexadecyl phosphate/phosphatidylcholine liposomes.
Interaction of poly-L-arginine with dihexadecyl phosphate/phosphatidylcholine liposomes.
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聚-L-精氨酸与磷酸二十六烷基酯/磷脂酰胆碱脂质体的相互作用。
DOI：
10.1021/la050475
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发表时间：
2005
期刊：
影响因子：
--
通讯作者：
C. M. Paleos
中科院分区：
文献类型：
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作者：
Ioannis Tsogas;D. Tsiourvas;G. Nounesis;C. M. Paleos
在本研究中，十六烷基磷酸钠盐：磷脂酰胆碱：胆固醇的摩尔比为1：19：9.5的混合脂质体与聚-L-精氨酸在脂质体膜主相变以下和以上的温度下相互作用。相互作用导致了聚集体的形成，聚集体的尺寸逐渐增大，最终沉淀下来。然而，在实验的初始阶段，当胍基团与磷酸盐的比例小于约40%时，可以确定它们的大小和电荷，并观察它们在水分散体中的形态。荧光实验证明，脂质体在与多聚L精氨酸相互作用过程中没有破裂。取而代之的是，它们通过胍-磷酸互补对连接在多肽链上。荧光猝灭实验表明，当脂质体分散体的温度低于主脂相转变温度时，聚L-精氨酸链能够与溶解在水相中的碘化物相互作用。然而，当温度超过这个主要的脂类相变时，它被分配到膜的内部。
In the present study, mixed liposomes of dihexadecyl phosphate sodium salt:phosphatidylcholine:cholesterol at a 1:19:9.5 molar ratio were allowed to interact with poly-L-arginine at temperatures below and above the main phase transition of the liposomal membrane. The interaction led to the formation of aggregates, which gradually increased in size and eventually precipitated. It was, however, possible, during the initial stage of the experiments, when the ratio of guanidinium group relative to phosphate was smaller than ca. 40%, to determine their size and charge and observe their morphology in aqueous dispersion. Fluorescence experiments established that the liposomes are not ruptured during their interaction with poly-L-arginine. Instead, they are attached at the polypeptide chain through the guanidinium-phosphate complementary pair. Fluorescence quenching experiments indicated that the poly-L-arginine chain is accessible for interaction with iodides dissolved in the aqueous phase when the temperature of the liposomal dispersion is below the main lipid phase transition. It is, however, partitioned in the interior of the membrane at temperatures exceeding this main lipid phase transition.