Effects of divalent cations on the physical, conformational and immunological properties of bovine allergen β-lactoglobulin aggregates. (15th January 2022)

• Record Type: Journal Article
• Authors: Li, Xin; Fei, Shuangwen; Xie, Xiuling; Tong, Ping; Yuan, Juanli; Wu, Zhihua; Yang, Anshu; Wu, Yong; Chen, Hongbing
• Is Part Of: Lebensmittel-Wissenschaft + Technologie =. Volume 154(2022)
• Publication Date: 2022-01-15
• Subjects: Aggregation -- β-lactoglobulin -- Divalent cations -- Characteristics -- Allergenicity; BLG β-lactoglobulin -- (BLG-W) BLG without metal ion treatment -- BLG-A Cu2+-induced β-lactoglobulin aggregates -- BLG-D Cu2+-induced β-lactoglobulin dimer -- USDA U.S. Department of Agriculture -- USDA DRI table U.S. Department of Agriculture Dietary Reference Intakes table -- SDS-PAGE Sodium dodecyl sulfate–polyacrylamide gel electrophoresis -- ANS 1-Anilinonaphthalene-8-sulfonate -- HRP Horseradish peroxidase -- DSC Differential scanning calorimetry -- FTIR Fourier transform infrared spectroscopy -- mMCP-1 Mast Cell Protease-1; Food industry and trade -- Periodicals; Food -- Composition -- Periodicals; Microbiology -- Periodicals; Nutrition -- Periodicals; 664.005
• DOI: 10.1016/j.lwt.2021.112557
• Languages: English
• ISSNs: 0023-6438

Abstract

Abstract: β-lactoglobulin is a major allergen in whey and always forms aggregates under different conditions. In our study, four kinds of divalent cations (Cu 2+, Mg 2+, Zn 2+ and Ca 2+ ) were used to induce the aggregation of β-lactoglobulin. The molecular interactions and characteristics, thermal stability and conformational structure of aggregates were monitored by silver staining, RP-HPLC, differential scanning calorimetry and spectroscopic methods, respectively. The immunological properties of Cu 2+ -induced β-lactoglobulin aggregates and dimers were evaluated in a Balb/c mouse model . The results showed that Cu 2+ promoted the highest β-lactoglobulin dimer levels compared with other metal ions. The thermal stability of aggregates induced by the four ions was more stable than that of native protein. The specific molecular interaction of aggregates induced by Mg 2+, Zn 2+ and Ca 2+ was disulfide bonding, while Cu 2+ -induced β-lactoglobulin aggregates were connected by disulfide bonds combined with other bonds. Specially, Cu 2+ -induced dimer showed decreased allergenicity and a shift from the Th2 response to the Th1 response that balances homeostasis compared with native BLG and Cu 2+ -induced aggregates. The results may provide a possible method to alleviate the allergenicity of bovine β-lactoglobulin by forming more dimers. Graphical abstract: Image 1 Highlight: Divalent cations elevated thermal stability of β-lactoglobulin aggregates. Divalent cations had no significant influence on protein secondary structure. Mg 2+, Ca 2+ and Zn 2+ strengthened hydrophobicity of β-lactoglobulin aggregates. Copper (Ⅱ) could reduce the allergenicity of β-lactoglobulin dimer.