Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry Russian Academy of Sciences 16/10 Miklukho-Maklaya str. Moscow 117997 Russia.
National Research Nuclear University MEPhI (Moscow Engineering Physics Institute) Kashirskoe shosse 31 Moscow 115409 Russian Federation.
ChemistryOpen. 2020 Apr 6;9(6):641-648. doi: 10.1002/open.201900276. eCollection 2020 Jun.
The synthetic function-spacer-lipid (FSL) amphiphile biotin-CMG-DOPE is widely used for delicate ligation of living cells with biotin residues under physiological conditions. Since this molecule has an "apolar-polar-hydrophobic" gemini structure, the supramolecular organization is expected to differ significantly from the classical micelle. Its organization is investigated with experimental methods and molecular dynamics simulations (MDS). Although the linear length of a single biotin-CMG-DOPE molecule is 9.5 nm, the size of the dominant supramer globule is only 14.6 nm. Investigations found that while the DOPE tails form a hydrophobic core, the polar CMG spacer folds back upon itself and predominantly places the biotin reside inside the globule or planar layer. MDS demonstrates that <10 % of biotin residues on the highly water dispersible globules and only 1 % of biotin residues in layer coatings are in an linear conformation and exposing biotin into the aqueous medium. This explains why in biotin-CMG-DOPE apolar biotin residues both in water dispersible globules and coatings on solid surfaces are still capable of interacting with streptavidin.
合成的功能间隔脂质（FSL）两亲体生物素-CMG-DOPE 广泛用于在生理条件下将带有生物素残基的活细胞进行精细连接。由于该分子具有“非极性-极性-疏水性”的双子结构，因此预期其超分子组织将与经典胶束有很大不同。使用实验方法和分子动力学模拟（MDS）对其组织进行了研究。尽管单个生物素-CMG-DOPE 分子的线性长度为 9.5nm，但主要超分子球的尺寸仅为 14.6nm。研究发现，虽然 DOPE 尾部形成疏水性核心，但极性 CMG 间隔物自身折叠，并主要将生物素残基置于球内或层内。MDS 表明，在高度可分散在水中的球上，只有<10%的生物素残基，以及在层涂层中，只有 1%的生物素残基呈线性构象，并将生物素暴露在水性介质中。这解释了为什么在具有疏水性的生物素-CMG-DOPE 球和固体表面的涂层中，极性生物素残基仍然能够与链霉亲和素相互作用。
