Pugliese Raffaele, Arnoldi Anna, Lammi Carmen
NeMO Lab, ASST Grande Ospedale Metropolitano Niguarda, 20162 Milan, Italy.
Department of Pharmaceutical Sciences, University of Milan, 20133 Milan, Italy.
Biomedicines. 2021 Mar 13;9(3):294. doi: 10.3390/biomedicines9030294.
Naturally occurring food peptides are frequently used in the life sciences due to their beneficial effects through their impact on specific biochemical pathways. Furthermore, they are often leveraged for applications in areas as diverse as bioengineering, medicine, agriculture, and even fashion. However, progress toward understanding their self-assembling properties as functional materials are often hindered by their long aromatic and charged residue-enriched sequences encrypted in the parent protein sequence. In this study, we elucidate the nanostructure and the hierarchical self-assembly propensity of a lupin-derived peptide which belongs to the α-conglutin (11S globulin, legumin-like protein), with a straightforward N-terminal biotinylated oligoglycine tag-based methodology for controlling the nanostructures, biomechanics, and biological features. Extensive characterization was performed via Circular Dichroism (CD) spectroscopy, Fourier Transform Infrared spectroscopy (FT-IR), rheological measurements, and Atomic Force Microscopy (AFM) analyses. By using the biotin tag, we obtained a thixotropic lupin-derived peptide hydrogel (named BT13) with tunable mechanical properties (from 2 to 11 kPa), without impairing its spontaneous formation of β-sheet secondary structures. Lastly, we demonstrated that this hydrogel has antioxidant activity. Altogether, our findings address multiple challenges associated with the development of naturally occurring food peptide-based hydrogels, offering a new tool to both fine tune the mechanical properties and tailor the antioxidant activities, providing new research directions across food chemistry, biochemistry, and bioengineering.
天然存在的食物肽因其通过影响特定生化途径而产生的有益作用，在生命科学中经常被使用。此外，它们还常常被应用于生物工程、医学、农业乃至时尚等诸多不同领域。然而，由于其母体蛋白质序列中加密的富含芳香族和带电荷残基的长序列，在理解它们作为功能材料的自组装特性方面的进展常常受到阻碍。在本研究中，我们阐明了一种羽扇豆衍生肽的纳米结构和分级自组装倾向，该肽属于α-伴球蛋白（11S球蛋白，豆球蛋白样蛋白），采用一种基于N端生物素化寡甘氨酸标签的直接方法来控制纳米结构、生物力学和生物学特性。通过圆二色光谱（CD）、傅里叶变换红外光谱（FT-IR）、流变学测量和原子力显微镜（AFM）分析进行了广泛的表征。通过使用生物素标签，我们获得了一种具有触变性的羽扇豆衍生肽水凝胶（命名为BT13），其机械性能可调（从2到11千帕），且不影响其β-折叠二级结构的自发形成。最后，我们证明了这种水凝胶具有抗氧化活性。总之，我们的研究结果解决了与基于天然食物肽的水凝胶开发相关的多个挑战，提供了一种既能微调机械性能又能定制抗氧化活性的新工具，为食品化学、生物化学和生物工程提供了新的研究方向。
