Wilde Sandra Catharina, Keppler Julia Katharina, Palani Kalpana, Schwarz Karin
Institute of Human Nutrition and Food Science, Food Technology, Christian-Albrechts-Universität zu Kiel, Heinrich-Hecht-Platz 10, 24118 Kiel, Germany.
Institute of Human Nutrition and Food Science, Food Technology, Christian-Albrechts-Universität zu Kiel, Heinrich-Hecht-Platz 10, 24118 Kiel, Germany.
Food Chem. 2016 Apr 15;197(Pt A):1015-21. doi: 10.1016/j.foodchem.2015.11.010. Epub 2015 Nov 9.
The binding reaction of allicin and diallyl disulfide with β-lactoglobulin and the influence of pH value and protein denaturation on this reaction have been examined in the present study. Regardless of the structural similarity of both the organosulfur compounds, their binding behavior was significantly different. Both ligands were covalently bound by the free thiol group of the protein, whereas the affinity for allicin was significantly higher. In addition, diallyl disulfide was non-covalently bound. The binding reaction of both ligands was very sensitive to the pH value during incubation. The optimal pH range was between pH 8.0 and 9.0. Protein denaturation increased the reaction rate and reduced the number of binding sites for allicin, whereas the number of non-covalent binding sites increased for diallyl disulfide. Based on these findings, it can be proposed that the covalent modification of β-lactoglobulin functions as a specific transporter stabilizing allicin or diallyl disulfide.
本研究考察了大蒜素和二烯丙基二硫化物与β-乳球蛋白的结合反应，以及pH值和蛋白质变性对该反应的影响。尽管这两种有机硫化合物结构相似，但其结合行为却有显著差异。两种配体均通过蛋白质的游离巯基共价结合，然而大蒜素的亲和力明显更高。此外，二烯丙基二硫化物还存在非共价结合。孵育过程中，两种配体的结合反应对pH值非常敏感。最佳pH范围在8.0至9.0之间。蛋白质变性提高了反应速率，减少了大蒜素的结合位点数量，而二烯丙基二硫化物的非共价结合位点数量增加。基于这些发现，可以推测β-乳球蛋白的共价修饰作为一种特异性转运体，可稳定大蒜素或二烯丙基二硫化物。
