Supramolecular and Biomaterials Chemistry, Leiden Institute of Chemistry, Leiden University, Einsteinweg 55, 2333 CC Leiden, The Netherlands.
Bioconjug Chem. 2020 Mar 18;31(3):834-843. doi: 10.1021/acs.bioconjchem.0c00009. Epub 2020 Feb 27.
Peptide stapling is a technique which has been widely employed to constrain the conformation of peptides. One of the effects of such a constraint can be to modulate the interaction of the peptide with a binding partner. Here, a cysteine bis-alkylation stapling technique was applied to generate structurally isomeric peptide variants of a heterodimeric coiled-coil forming peptide. These stapled variants differed in the position and size of the formed macrocycle. C-terminal stapling showed the most significant changes in peptide structure and stability, with calorimetric binding analysis showing a significant reduction of binding entropy for stapled variants. This entropy reduction was dependent on cross-linker size and was accompanied by a change in binding enthalpy, illustrating the effects of preorganization. The stapled peptide, along with its binding partner, were subsequently employed as fusogens in a liposome model system. An increase in both lipid- and content-mixing was observed for one of the stapled peptide variants: this increased fusogenicity was attributed to increased coiled-coil binding but not to membrane affinity, an interaction theorized to be a primary driving force in this fusion system.
肽键是一种广泛应用于约束肽构象的技术。这种约束的一个影响可以调节肽与结合伴侣的相互作用。在这里，应用半胱氨酸双烷基化键合技术来生成具有异构结构的二聚体卷曲螺旋形成肽的肽键键合变体。这些键合变体在形成的大环的位置和大小上有所不同。C 端键合显示出对肽结构和稳定性的最显著变化，量热结合分析显示键合变体的结合熵显著降低。这种熵的降低取决于交联剂的大小，并伴随着结合焓的变化，说明了预组织的影响。该键合肽及其结合伴侣随后被用作脂质体模型系统中的融合剂。观察到其中一种键合肽变体的脂质和内容物混合均增加：这种融合性的增加归因于增加的卷曲螺旋结合，但不是膜亲和力，这种相互作用被认为是该融合系统的主要驱动力。
