Landman Jasper, Ouhajji Samia, Prévost Sylvain, Narayanan Theyencheri, Groenewold Jan, Philipse Albert P, Kegel Willem K, Petukhov Andrei V
Van 't Hoff Laboratory for Physical & Colloid Chemistry, 3584 CH Utrecht, Netherlands.
European Synchrotron Radiation Facility, 38000 Grenoble, France.
Sci Adv. 2018 Jun 29;4(6):eaat1817. doi: 10.1126/sciadv.aat1817. eCollection 2018 Jun.
Striking morphological similarities found between superstructures of a wide variety of seemingly unrelated crystalline membrane systems hint at the existence of a common formation mechanism. Resembling systems such as multiwalled carbon nanotubes, bacterial protein shells, or peptide nanotubes, the self-assembly of SDS/β-cyclodextrin complexes leads to monodisperse multilamellar microtubes. We uncover the mechanism of this hierarchical self-assembly process by time-resolved small- and ultrasmall-angle x-ray scattering. In particular, we show that symmetric crystalline bilayers bend into hollow cylinders as a consequence of membrane line tension and an anisotropic elastic modulus. Starting from single-walled microtubes, successive nucleation of new cylinders inside preexisting ones drives an inward growth. As both the driving forces that underlie the self-assembly behavior and the resulting morphologies are common to systems of ordered membranes, we believe that this formation mechanism has a similarly general applicability.
在各种看似不相关的晶体膜系统的上层结构之间发现了惊人的形态相似性，这暗示着存在一种共同的形成机制。类似于多壁碳纳米管、细菌蛋白壳或肽纳米管等系统，SDS/β-环糊精复合物的自组装会产生单分散的多层微管。我们通过时间分辨小角和超小角X射线散射揭示了这种分级自组装过程的机制。特别是，我们表明对称的晶体双层由于膜线张力和各向异性弹性模量而弯曲成空心圆柱体。从单壁微管开始，在已存在的圆柱体内新圆柱体的连续成核驱动向内生长。由于有序膜系统的自组装行为背后的驱动力和由此产生的形态都是共同的，我们相信这种形成机制具有类似的普遍适用性。
