限制性酶解对11S球蛋白结构的影响研究

目的]研究限制性酶解对11S球蛋白结构的影响。方法]采用碱性蛋白酶对11S球蛋白进行限制性酶解,并利用SDS-聚丙烯酰胺凝胶电泳(SDS-PAGE)、扫描电镜(SEM)、傅里叶红外光谱(FTIR)、疏水性和巯基含量的变化等手段,研究酶解对11S蛋白结构的影响。结果]由SDS-PAGE电泳分析结果可知,酶解后的电泳图谱发生了很大变化,11S的亚基含量均显著降低,且酸性亚基较碱性亚基更易被水解;粉体的扫描电镜分析结果表明,所有酶解后的样品在相同的观察条件下,其粉体结构均发生了明显改变;FTIR的结果表明,蛋白在酶法水解过程中各种构象所占的比例发生了很大变化;由疏水性和巯基含量的分析结果可知,蛋白的疏水性和巯基含量受水解度的影响较大。结论]酶解导致11S球蛋白的构象发生了很大变化,且构象变化的程度取决于水解的程度。

Effect of the Limited Enzymatic Hydrolysis on the Structure Characterization of Glycinin

Objective] This study aimed to characterize the structure of glycinin affected by limited enzymatic hydrolysis.Mehtod] The glycinin was hydrolyzed with alkaline protease;then the SDS-polyacrylamide gel electrophoresis(SDS-PAGE),scanning electron microscopy(SEM),Fourier transform infrared spectroscopy(FTIR) and other means were performed to characterize the structure of glycinin changing during the hydrolysis process.Result] SDS-PAGE analysis showed that subunit content of glycinin significantly decreased after hydrolysis,and acidic subunits was more susceptible to hydrolysis than alkaline subunits.The scanning electron microscopy revealed that the glycinin powder structure changed greatly after hydrolysis.The FTIR results showed that the proportions of all the glycinin conformations changed greatly during hydrolysis process.In addition,the protein hydrophobicity and sulfhydryl content were also significantly influenced by hydrolysis.Conclusion] The enzymatic hydrolysis greatly changed the conformation of glycinin,and the change was dependent on the degree of hydrolysis.