DataSheet1_Hierarchical self-assembly of a reflectin-derived peptide.docx

Reflectins are a family of intrinsically disordered proteins involved in cephalopod camouflage, making them an interesting source for bioinspired optical materials. Understanding reflectin assembly into higher-order structures by standard biophysical methods enables the rational design of new materials, but it is difficult due to their low solubility. To address this challenge, we aim to understand the molecular self-assembly mechanism of reflectin’s basic unit—the protopeptide sequence YMDMSGYQ—as a means to understand reflectin’s assembly phenomena. Protopeptide self-assembly was triggered by different environmental cues, yielding supramolecular hydrogels, and characterized by experimental and theoretical methods. Protopeptide films were also prepared to assess optical properties. Our results support the hypothesis for the protopeptide aggregation model at an atomistic level, led by hydrophilic and hydrophobic interactions mediated by tyrosine residues. Protopeptide-derived films were optically active, presenting diffuse reflectance in the visible region of the light spectrum. Hence, these results contribute to a better understanding of the protopeptide structural assembly, crucial for the design of peptide- and reflectin-based functional materials.

反光蛋白（Reflectins）是一类参与头足类伪装的内在无序蛋白（intrinsically disordered proteins）家族，因此成为仿生光学材料领域极具潜力的研究来源。通过标准生物物理方法解析反光蛋白组装为高级结构的过程，可实现新型材料的理性设计，但由于其溶解度极低，该研究颇具挑战。为解决这一难题，我们旨在通过解析反光蛋白的基本单元——原型肽序列YMDMSGYQ的分子自组装机制，阐明反光蛋白的组装现象。该原型肽可通过不同环境触发因子启动自组装，形成超分子水凝胶，并通过实验与理论方法进行表征。此外，我们还制备了原型肽薄膜以评估其光学性能。我们的研究结果在原子尺度上支持了该原型肽的聚集模型假说，该模型由酪氨酸残基介导的亲水与疏水相互作用主导。基于原型肽制备的薄膜具备光学活性，在可见光光谱区域呈现漫反射特性。综上，本研究结果有助于更深入地理解原型肽的结构组装过程，这对于开发基于肽与反光蛋白的功能材料至关重要。