State Key Laboratory of Heavy Oil Processing and Department of Biological and Energy Engineering, China University of Petroleum (East China), 66 Changjiang West Road, Qingdao 266580, China.
State Key Laboratory of Heavy Oil Processing and Department of Biological and Energy Engineering, China University of Petroleum (East China), 66 Changjiang West Road, Qingdao 266580, China.
J Colloid Interface Sci. 2023 Jan;629(Pt A):1-10. doi: 10.1016/j.jcis.2022.08.104. Epub 2022 Aug 17.
Self-assembly of peptides is influenced by both molecular structure and external conditions, which dictate the delicate balance of different non-covalent interactions that driving the self-assembling process. The shifting of terminal charge residue is expected to influence the non-covalent interactions and their interplay, thereby affecting the morphologies of self-assemblies. Therefore, the morphology transition can be realized by shifting the position of the terminal charge residue.
The structure transition from thin nanofibers to giant nanotubes is realized by simply shifting the C-terminal lysine of ultrashort Ac-IK-NH to its N-terminus. The morphologies and detailed structure information of the self-assemblies formed by these two peptides are investigated systemically by a combination of different experimental techniques. The effect of terminal residue on the morphologies of the self-assemblies is well presented and the underlying mechanism is revealed.
Giant nanotubes with a bilayer shell structure can be self-assembled by the ultrashort peptide Ac-KI-NH with the lysine residue close to the N-terminal. The Ac-KI-NH dimerization through intermolecular C-terminal H-bonding promotes the formation of a bola-form geometry, which is responsible for the wide nanotube assembly formation. The evolution process of Ac-KI-NH nanotubes follows the "growing width" model. Such a morphological transformation with the terminal lysine shift is applicable to other analogues and thus provides a facile approach for the self-assembly of wide peptide nanotubes, which can expand the library of good template structures for the prediction of peptide nanostructures.
肽的自组装受分子结构和外部条件的影响，这些因素决定了不同非共价相互作用的微妙平衡，驱动着自组装过程。末端电荷残基的转移预计会影响非共价相互作用及其相互作用，从而影响自组装体的形态。因此，可以通过改变末端电荷残基的位置来实现形态转变。
通过简单地将超短 Ac-IK-NH 的 C 端赖氨酸转移到其 N 端，实现了从薄纳米纤维到巨大纳米管的结构转变。通过不同实验技术的组合，系统地研究了这两种肽形成的自组装体的形态和详细结构信息。很好地展示了末端残基对自组装体形态的影响，并揭示了其潜在机制。
具有双层壳结构的巨大纳米管可以通过靠近 N 端的赖氨酸残基的超短肽 Ac-KI-NH 自组装。通过分子间 C 端氢键的二聚化促进了 bola 形几何形状的形成，这是形成广泛纳米管组装的原因。Ac-KI-NH 纳米管的演化过程遵循“增宽”模型。这种末端赖氨酸转移的形态转变适用于其他类似物，从而为广泛的肽纳米管的自组装提供了一种简便的方法，这可以扩展用于预测肽纳米结构的良好模板结构库。
