State Key Laboratory of Food Nutrition and Safety, College of Food Science and Technology, Tianjin University of Science & Technology, Tianjin 300457, China.
Beijing Key Laboratory of Flavor Chemistry, Beijing Technology and Business University (BTBU), Beijing 100048, China.
Food Chem. 2021 Nov 1;361:130069. doi: 10.1016/j.foodchem.2021.130069. Epub 2021 May 12.
Ferritin, a protein with an 8-nm cage structure, can encapsulate and deliver bioactive molecules. In this study, succinylation was adopted to modify plant ferritin to fabricate succinylated red been ferritin (SRBF) at pH 8.0. The SRBF was retained as a cage-like shape (12 nm diameter), while its secondary structure was altered, rendering higher negative charge accompanies by decreased surface hydrophobicity. The SRBF also demonstrated favorable property of reversible assembly regulated by pH-transitions (pH 2.0/7.0), thus enabled successful encapsulation of epigallocatechin gallate (EGCG) for fabrication of EGCG-loaded SRBF complexes with a diameter of ~12 nm. Succinylation enhanced the thermal stabilities of ferritin and the embedded EGCG. Moreover, SRBF markedly improved the transport efficiency of EGCG in Caco-2 monolayers relative to EGCG and that encapsulated in unmodified ferritin. These findings have extended the succinylation reaction for the cage-like protein modification, and facilitated the usage of ferritin variant in delivery of bioactive molecules.
铁蛋白是一种具有 8nm 笼状结构的蛋白质，能够包裹和输送生物活性分子。本研究采用琥珀酰化修饰植物铁蛋白，在 pH8.0 下制备琥珀酰化红芸豆铁蛋白（SRBF）。SRBF 保持笼状形状（直径 12nm），但其二级结构发生改变，带更多负电荷，表面疏水性降低。SRBF 还表现出 pH 转变（pH2.0/7.0）调控的可逆组装特性，从而成功封装表没食子儿茶素没食子酸酯（EGCG），制备直径约 12nm 的 EGCG 负载的 SRBF 复合物。琥珀酰化增强了铁蛋白和嵌入 EGCG 的热稳定性。此外，与 EGCG 和未修饰铁蛋白包封的 EGCG 相比，SRBF 显著提高了 EGCG 在 Caco-2 单层中的转运效率。这些发现扩展了笼状蛋白修饰的琥珀酰化反应，并促进了铁蛋白变体在生物活性分子输送中的应用。
