Engineering Laboratory for Agro Biomass Recycling and Valorizing, College of Engineering, China Agricultural University, Beijing, People's Republic of China.
Beijing Engineering Research Center of Protein and Functional Peptides, China National Research Institute of Food and Fermentation Industries Co., Ltd, Beijing, People's Republic of China.
J Sci Food Agric. 2024 Oct;104(13):8150-8161. doi: 10.1002/jsfa.13647. Epub 2024 Jun 5.
In our previous study, we successfully identified five peptides from wheat gluten: Ala-Pro-Ser-Tyr (APSY), Leu-Tyr (LY), Pro-Tyr (PY), Arg-Gly-Gly-Tyr (RGGY) and Tyr-Gln (YQ). Molecular docking and molecular dynamics simulation methods were employed to investigate the interaction between these antioxidant peptides and the Kelch-like ECH-associated protein 1 (Keap1 protein), revealing the molecular mechanism of their non-competitive binding. In addition, the total antioxidant capacity of the five peptides was determined using the 2,2'-azinobis(3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt (ABTS) method.
The affinities of APSY, LY, PY, RGGY and YQ were -8.9, -8.3, -8.5, -9.1 and - 7.9 kcal mol, respectively. The five peptides effectively bound to Keap1 protein through hydrogen, π-σ, π-alkyl and alkyl interactions. Significant roles were observed for the P1 pocket residue ARG-415 and the P3 pocket residue ALA-556 in the interactions of the Keap1-peptide complexes. Molecular dynamics simulations further elucidated the dynamic process of peptide binding to the Keap1 protein. All five peptides formed stable complexes with Keap1 protein, with van der Waals forces playing crucial roles in these complex systems, indicative of the peptides' strong binding ability to Keap1 protein. The van der Waals forces were -178.74, -123.11, -134.36, -132.59, and -121.44 kJ mol for the Keap1-APSY, Keap1-LY, Keap1-PY, Keap1-RGGY and Keap1-YQ complexes, respectively. These peptides exhibited excellent antioxidant effects. Among them, the YQ peptide exhibited the highest total antioxidant capacity, with an activity value of 1.18 ± 0.06 mmol Trolox equivalent (TE) L at a concentration of 0.10 mg mL. The RGGY, PY, LY and APSY peptides followed in descending order, with activity values of 0.91 ± 0.05, 0.72 ± 0.06, 0.62 ± 0.04 and 0.60 ± 0.05 mmol TE L, respectively.
These results unveiled the molecular mechanism by which the five antioxidant peptides act on active pockets through the Keap1-Nrf2 signaling pathway, providing a theoretical basis for the development of antioxidants. © 2024 Society of Chemical Industry.
在我们之前的研究中，我们成功地从小麦面筋中鉴定出五种肽：丙氨酰-脯氨酰-丝氨酰-酪氨酸（APSY）、亮氨酰-酪氨酸（LY）、脯氨酰-酪氨酸（PY）、精氨酰-甘氨酰-甘氨酰-酪氨酸（RGGY）和酪氨酸-谷氨酰胺（YQ）。采用分子对接和分子动力学模拟方法研究了这些抗氧化肽与 Kelch 样 ECH 相关蛋白 1（Keap1 蛋白）之间的相互作用，揭示了它们非竞争性结合的分子机制。此外，使用 2,2'-联氮-双（3-乙基苯并噻唑啉-6-磺酸）二铵盐（ABTS）法测定了五种肽的总抗氧化能力。
APSY、LY、PY、RGGY 和 YQ 的亲和力分别为-8.9、-8.3、-8.5、-9.1 和-7.9 kcal/mol。五种肽通过氢键、π-σ、π-烷基和烷基相互作用有效地与 Keap1 蛋白结合。在 Keap1-肽复合物的相互作用中，P1 口袋残基 ARG-415 和 P3 口袋残基 ALA-556 发挥了重要作用。分子动力学模拟进一步阐明了肽与 Keap1 蛋白结合的动态过程。五种肽均与 Keap1 蛋白形成稳定的复合物，范德华力在这些复合物系统中起着关键作用，表明这些肽与 Keap1 蛋白具有很强的结合能力。Keap1-APSY、Keap1-LY、Keap1-PY、Keap1-RGGY 和 Keap1-YQ 复合物的范德华力分别为-178.74、-123.11、-134.36、-132.59 和-121.44 kJ/mol。这些肽表现出优异的抗氧化作用。其中，YQ 肽表现出最高的总抗氧化能力，在浓度为 0.10 mg/mL 时，活性值为 1.18±0.06 mmol Trolox 当量（TE）/L。RGGY、PY、LY 和 APSY 肽的活性值依次降低，分别为 0.91±0.05、0.72±0.06、0.62±0.04 和 0.60±0.05 mmol TE/L。
这些结果揭示了五种抗氧化肽通过 Keap1-Nrf2 信号通路作用于活性口袋的分子机制，为抗氧化剂的开发提供了理论依据。© 2024 化学工业协会。
