Influence of central sidechain on self-assembly of glycine-x-glycine peptides
Influence of central sidechain on self-assembly of glycine-x-glycine peptides
复制标题
中心侧链对甘氨酸-x-甘氨酸肽自组装的影响
DOI：
10.1039/d2sm01082h
复制
发表时间：
2023
期刊：
影响因子：
3.4
通讯作者：
Alvarez, Nicolas J.
中科院分区：
文献类型：
--
作者：
Thursch, Lavenia J.;Lima, Thamires A.;O’Neill, Nichole;Ferreira, Fabio F.;Schweitzer-Stenner, Reinhard;Alvarez, Nicolas J.
低分子量胶凝剂（LMWG）是一系列生物医学和工程应用的密集研究的主题。肽是一类特殊的LMWG，它提供了无限的序列可能性，因此，工程性质。这项工作研究的倾向GxG肽家族，其中x表示一个客人残基，通过pH值和乙醇浓度的变化自组装成原纤维网络。这些凝胶化的触发因素是由最近对GHG和GAG的研究激发的，GHG和GAG出人意料地自组装成具有独特流变性质的厘米长的原纤维网络。GxG肽自组装的倾向，以及自组装结构的物理和化学性质的特征在于通过显微镜，光谱学，流变学和X-射线衍射。有趣的是，我们表明，结晶自组装聚集体的数量，长度，大小和形态显着依赖于X-残基化学和溶液条件，即pH值，温度，肽浓度等不同的X-残基使我们能够探测不同的肽相互作用的重要性，例如π-π堆积，氢键和疏水性，对原纤维的形成。我们的结论是，原纤的形成需要在纯水中的π-π堆积相互作用，而氢键可以在乙醇-水溶液中形成原纤。这些结果验证和支持的理论论点的倾向自组装，并导致更好地理解肽化学和原纤维自组装之间的关系。总的来说，GxG肽构成了一个独特的肽家族，其表征将有助于推进我们对肽系统中原纤维形成的自组装驱动力的理解。
Low molecular weight gelators (LMWGs) are the subject of intense research for a range of biomedical and engineering applications. Peptides are a special class of LMWG, which offer infinite sequence possibilities and, therefore, engineered properties. This work examines the propensity of the GxG peptide family, where x denotes a guest residue, to self-assemble into fibril networks via changes in pH and ethanol concentration. These triggers for gelation are motivated by recent work on GHG and GAG, which unexpectedly self-assemble into centimeter long fibril networks with unique rheological properties. The propensity of GxG peptides to self-assemble, and the physical and chemical properties of the self-assembled structures are characterized by microscopy, spectroscopy, rheology, and X-ray diffraction. Interestingly, we show that the number, length, size, and morphology of the crystalline self-assembled aggregates depend significantly on the x-residue chemistry and the solution conditions, i.e. pH, temperature, peptide concentration, etc. The different x-residues allow us to probe the importance of different peptide interactions, e.g. π–π stacking, hydrogen bonding, and hydrophobicity, on the formation of fibrils. We conclude that fibril formation requires π–π stacking interactions in pure water, while hydrogen bonding can form fibrils in the presence of ethanol–water solutions. These results validate and support theoretical arguments on the propensity for self-assembly and leads to a better understanding of the relationship between peptide chemistry and fibril self-assembly. Overall, GxG peptides constitute a unique family of peptides, whose characterization will aid in advancing our understanding of self-assembly driving forces for fibril formation in peptide systems.