摘要
本文以大豆为原料,分离大豆球蛋白中酸、碱性链,并探讨酸、碱性链在微生物转谷氨酰胺酶(MTG)介导下参与交联反应的差异性。利用等电点沉淀、凝胶过滤层析以及亲和层析分离得到纯度大于94%的大豆球蛋白,再通过热变性、β-巯基乙醇(β-ME)还原和等电点沉淀分离大豆球蛋白酸和碱性链,并对其进行了电泳鉴定和氨基酸分析;进一步以MTG催化大豆球蛋白及其酸、碱性链交联,利用SDS-PAGE和溶解性试验探讨大豆球蛋白酸、碱性链交联特性和交联产物的溶解性。结果表明大豆球蛋白酸、碱性链都是MTG的有效底物,均可参与交联反应并形成高聚物,但碱性链反应率较酸性链低,两者参与交联反应差异受其谷氨酰胺和赖氨酸残基含量的影响较小,而受其疏水性氨基酸含量影响较大。
Using soybean as the raw material,the acidic and basic polypeptides of glycinin were isolated,and the differences between their effects in microbial transglutaminase（MTG）-mediated cross-linking were explored.Glycinin was obtained with a purity of more than 94% from soybean protein by isoelectric precipitation,gel filtration chromatography,and affinity chromatography.The acidic and basic polypeptides were isolated by isoelectric precipitation after heat denaturation and reduction with β-mercaptoethanol,and then characterized by electrophoresis and amino acid analysis.Furthermore,sodium dodecyl sulfate polyacrylamide gel electrophoresis（SDS-PAGE） and dissolution experiments were performed to determine the effects of acidic and basic polypeptides on enzymatic cross-linking and the solubility of the cross-linked products.The results suggested that both the acidic and basic polypeptides were effective substrates for MTG and could participate in the cross-linking reaction to form polymers with high molecular weight;however,the reaction rate of basic polypeptides was lower than that of acidic polypeptides.The differences between the acidic and basic polypeptides in the cross-linking reaction were slightly affected by the glutamine and lysine residue content,and were significantly affected by the hydrophobic amino acid content.
作者
夏佳恒
龚育清
吴蕾蕾
王艳
杨安树
陈红兵
XIA Jia-heng GONG Yu-qing WU Lei-lei WANG Yan YANG An-shu CHEN Hong-bing(State Key Laboratory of Food Science and Technology, Nanchang University, Nanchang 330047, China Sino-German Joint Research Inst. Nanchang University, Nanchang 330047, China)
出处
《现代食品科技》
EI
CAS
北大核心
2017年第2期55-60,共6页
Modern Food Science and Technology
基金
国家自然科学基金项目(31460439)
国家自然科学基金项目(31460439)
国家高技术研究发展计划(863计划)项目(2013AA102205)
关键词
大豆球蛋白
酸性和碱性链
分离
微生物转谷氨酰胺酶
酶交联
glycinin
acidic and basic polypeptides
protein purification
microbial transglutaminase
enzymatic cross-linking
