枯草杆菌蛋白酶嗜热性改造单突变效果评判方法研究

摘要

对蛋白质进行嗜热性改造是蛋白质工程的主要问题之一，残基突变方法被广泛运用于其中。本文以枯草杆菌蛋白酶（SUBTILISIN BPN′）为研究对象，旨在建立评判嗜热性改造效果的方法，选取了有可靠实验资料的9个突变点，运用分子动力学模拟方法，在四种不同模拟条件下，对其中的6个突变体和1个野生型蛋白进行了多种参量的对比分析，提取4个特征有效参量，建立了蛋白酶嗜热性改造单突变效果评判方法；利用该方法对其它3个突变效果进行评判，评判结果与实验资料完全吻合，证明该方法可用于枯草杆菌蛋白酶嗜热性改造单突变效果的评判。%The modification of protein thermostability is one of the major topics of protein engineering, where the strategy of residue mutation is widely used. This article aims to establish a method of evaluating the effect of the mutation results. In this article, we chose Subtilisin BPN′as our research object and picked its 9 point mutations as our research samples. By using molecular dynamics simulation method in 4 different simulated conditions, we compared and analysed some parameters between the wild and 6 mutated proteins, collected 4 parameters of them as the effective parameters, and established the evaluation method of SUBTILISIN BPN′s thermostability transformation effect on a single mutation. We used this method to evaluate the other three mutations′effects, and found the results were completely coincided with the existing data, suggesting that the method can be used to evaluate the SUBTILISIN BPN′s thermostability transformation effect on a single mutation.