脲或盐酸胍溶液中变性溶菌酶复性过程中集聚体的研究

建立在蛋白质变性-复性三态模型的基础上, 给出了一个描述在变性液中变性蛋白质复性时蛋白质浓度和其复性率的关系式. 通过这个关系式, 可以获得两个重要的描述蛋白质变性-复性体系特征的参数, 一个是包含在一个集聚体分子中的变性蛋白质的分子数目n, 另一个是蛋白质从原始态到形成集聚体过程中的表观集聚平衡常数K. 以三种溶菌酶在脲和盐酸胍溶液中的变性-复性过程对此方程进行了验证, 结果表明所给出的方程能够很好地描述三种溶菌酶在这两种变性液中的复性结果, 三种溶菌酶在两种变性液中有形成二分子集聚体的趋势. 变性溶菌酶在复性过程中的电泳和高效凝胶排阻色谱也同时能够监测到复性过程中集聚体的形成, 并且监测结果与上述方程所得的结果一致.

Study on Aggregate for Denatured Lysozyme Renaturation in Urea and Guanidine Hydrochloride Solutions

Based on the three-state model of protein denaturation-renaturation, an equation describing the effect of protein concentration in denaturant solution on renaturation yield of denatured protein was pre- sented. Through this equation two important parameters, the number n of denatured protein molecules in- cluded in an aggregate and the apparent aggregation equilibrium constant K for protein denaturation from native state to aggregate state, could be simultaneously derived. By using lysozyme as model protein, this equation was tested with the renaturation process of three kinds of denatured lysozyme molecules in urea and guanidine hydrochloride solutions, and it was found that the renaturation results of denatured lysozymes could be described well by this equation, and these denatured lysozyme molecules had a tendency to form a bi-molecular intermediate aggregate in both solutions. This result was further confirmed with their SDS-PAGE and high-performance size-exclusion chromatography.