National Research and Development Center for Egg Processing, College of Food Science and Technology, Huazhong Agricultural University, Wuhan 430070, China.
National Research and Development Center for Egg Processing, College of Food Science and Technology, Huazhong Agricultural University, Wuhan 430070, China.
Food Chem. 2021 Aug 1;352:129457. doi: 10.1016/j.foodchem.2021.129457. Epub 2021 Mar 3.
The mechanism by which sodium tripolyphosphate affected the aggregation behavior of ovalbumin-lysozyme complexes was investigated in this work. The highest stability coefficients were detected for natural ovalbumin and lysozyme at pH 9.0 and pH 5.0, with values of 0.981 and 0.931, respectively. The turbidity of the phosphorylated ovalbumin-lysozyme complexes was 1.71-fold to the natural complexes at pH 7.0. This result was related to the fact that the phosphorylated sample had a lower isoelectric point. Besides, both intermolecular forces and SDS-PAGE analysis indicated that the disulfide bond was the most important interaction in the complex. Circular dichroism analysis showed that phosphorylation weakened the unfolding and stretching of the structure caused by heat treatment. Moreover, transmission electron microscopy pictures confirmed that the network structure of phosphorylated ovalbumin-lysozyme complex was broader than natural protein. This study provides information for further understanding the effect of phosphorylation on protein aggregation behavior.
本研究考察了三聚磷酸钠影响卵清蛋白-溶菌酶复合物聚集行为的机制。在 pH 值为 9.0 和 pH 值为 5.0 时，天然卵清蛋白和溶菌酶的稳定性系数最高，分别为 0.981 和 0.931。在 pH 值为 7.0 时，磷酸化卵清蛋白-溶菌酶复合物的浊度是天然复合物的 1.71 倍。这一结果与磷酸化样品具有较低等电点有关。此外，分子间作用力和 SDS-PAGE 分析表明，二硫键是复合物中最重要的相互作用。圆二色性分析表明，磷酸化削弱了热处理引起的结构展开和拉伸。此外，透射电子显微镜图片证实，磷酸化卵清蛋白-溶菌酶复合物的网络结构比天然蛋白质更宽。本研究为进一步了解磷酸化对蛋白质聚集行为的影响提供了信息。
