卵黏蛋白复合体凝胶特性在蛋清稀化过程中的动态转化规律与分子机制

项目名称： 卵黏蛋白复合体凝胶特性在蛋清稀化过程中的动态转化规律与分子机制

项目编号： No.31501506

项目类型： 青年科学基金项目

立项/批准年度： 2016

项目学科： 农业科学

项目作者： 单媛媛

作者单位： 西北农林科技大学

项目金额： 21万元

中文摘要： 蛋清稀化是蛋品质劣变的重要指标，卵黏蛋白复合体是维持蛋清天然凝胶特性的关键成分，而对这类重要的蛋白质复合体在蛋清稀化过程中的动态变化规律与机制却并不清楚。本课题以蛋清中的卵黏蛋白复合体为研究对象，应用质谱技术结合FI-IR、CD、DLS、生物电镜及流变学等技术手段对该复合体的组成、结构与超分子特性进行鉴定与表征，进而分析其构象与凝胶特性在蛋清稀化过程中的转变规律；应用聚类和判别分析及指数回归模型筛选与卵黏蛋白复合体变化显著相关的关键蛋清环境参数，进一步研究分子大小、蛋白浓度以及pH、离子强度等关键因素对该蛋白质复合体组成、超分子构象、分子间相互作用与凝胶特性的影响，分析复合体中关键蛋白的转化动力学，以探讨卵黏蛋白复合体的凝胶特性在蛋清稀化过程中转变的分子机制，最终从卵黏蛋白复合体超分子构象动态变化的角度揭示蛋清稀化的生化机制，为蛋品质变化机理的深入研究和鲜蛋的贮运保鲜提供理论。

中文关键词： 蛋清稀化；黏蛋白复合体；流变学特性；超分子结构

英文摘要： Thinning of egg white is regarded as a sensitive indicator for egg quality deterioration. Ovomucin complex has been considered to be the key to maintaining the viscoelastic properties of egg white. However, there is lack in understanding of the dynamic changes of this important protein complex during egg white thinning, and the molecular mechanism of ovomucin complex transition is still not clear. To solve this issue, mass spectrometry combined with FI-IR、CD、DLS、biological electron microscopy, rheological technologies are applied to identify and characterize the composition and molecular properties of ovomucin complex. Transformation regularities of ovomucin complex composition and molecular properties during egg white thinning are further investigated. Statistical methods such as clustering and discriminant analysis as well as exponential regression model are implied to explore the relationship between ovomucin complex conformational changes and egg white quality. Key environmental parameters of egg white, significantly associated with ovomucin complex changes are then selected. Then, the effect of degree of polymerization, protein concentration, and pH, ionic strength of the protein complex on supramolecular conformation, intermolecular interactions and the rheological properties of ovomucin complex are studied. Exploration of the transformation kinetics of key proteins will be also involved; This project attempts to explain the possible molecular mechanisms of egg white thinning from the view of supramolecular conformational dynamics change of ovomucin complex, thus further to provide a theoretical basis for the clarification of the egg quality changes mechanism during storage.

英文关键词： thning of egg white;ovomucin complex;Rheological properties;Supramolecular conformation