Modulation of Density and Orientation of Amphiphilic DNA Anchored to Phospholipid Membranes. I. Supported Lipid Bilayers
Modulation of Density and Orientation of Amphiphilic DNA Anchored to Phospholipid Membranes. I. Supported Lipid Bilayers
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DOI：
10.1021/jp100730x
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发表时间：
2010-06-03
影响因子：
3.3
通讯作者：
Baglioni, Piero
中科院分区：
文献类型：
--
作者：
Gambinossi, Filippo;Banchelli, Martina;Baglioni, Piero
在本系列论文中，我们描述了将胆固醇标记的寡核苷酸锚定到磷脂层上，然后在溶液中进行膜辅助互补链杂交的系统研究结果。本文描述了新型胆固醇修饰的 DNA-18mers 在 1-棕榈酰-2-油酰-sn-甘油-3-磷酸胆碱支持的脂质双层 (SLB) 中的锚定：我们比较了两种锚定功能的行为，这两种锚定功能在胆固醇单位数量和间隔基团长度方面有所不同。带阻抗监测的石英晶体微天平 (QCM-Z) 测量表明，两种寡核苷酸通过胆固醇锚定插入双层膜：然而，随着锚定单元数量的增加，在表面组织和厚度方面发现显着差异。在多个胆固醇单元的情况下，揭示了一种特殊的三态浓度依赖性，并且与吸附单元的有效尺寸相关。有趣的是，对于高寡核苷酸浓度，吸附过程根据两亲 DNA 分子的压缩模型合理化。 SLB 锚定双链的 QCM-Z 温度循环为双层界面的可逆杂交提供了明确的证据。
In the present series of papers, we describe the results of a systematic study on the anchoring of cholesterol-tagged oligonucleotides to phospholipids hi layers followed by membrane-assisted hybridization of the complementary strand in solution. This paper describes the anchoring of novel cholesterol-modified DNA-18mers in supported lipid bilayers (SLB) of 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine: we compared the behavior of two anchoring functionalities differing in the number of cholesterol units and in the length of a spacer group. Quartz Crystal Microbalance with impedance monitoring (QCM-Z) measurements showed that both oligonucleotides insert into the bilayer membrane through cholesterol anchoring: however, dramatic differences, in terms of surface organization and thickness, arc found as the number of anchoring units increases. In the case of multiple cholesterol units, a peculiar three-regimes concentration dependence was revealed and correlated to the effective size of the adsorbing units. Interestingly, for high oligonucleotide concentration, the adsorption process was rationalized in terms of a compaction model of amphiphilic DNA molecules. QCM-Z temperature cycles of the SLB-anchored double strands provided clear evidence for reversible hybridization at the bilayer interface.