圆二色谱法测定饥饿细胞DNA结合蛋白的突变热点

目的通过引入人为突变,研究DPS分子的稳定性与其一级结构的关系,寻找新型DPS分子。方法选择可能与DPS构象密切相关的氨基酸残基引入突变,经表达、纯化后,利用圆二色谱仪检测突变体蛋白分子的结构变化。结果关键部位氨基酸的突变可以引起DPS分子中α螺旋含量发生了显著的变化。结论某些氨基酸的改变会引起DPS分子整体结构与稳定性的变化,有可能影响、甚至改变蛋白质分子的功能。

Detection of the stability of DPS nano capsule via circular dichroism

Objective To study the effects of single amino acid mutation on the stability of DNA-binding proteins from starved cells(DPS), and to explore the relationship between the amino acid sequence and the structure of whole nano capsule.Methods The amino acids which might affect the conformation were mutated artificially.Circular Dichroism(CD) was applied to collect the parameters of the molecule structure.Results Single amino acid mutation could cause huge changes to the percentage of α helix of the DPS capsule.Conclusions The amino acids are important to keep DPS molecule intact.The mutations could introduce changes to the structure of the molecule and thus change its feature and function, which may help us better understand the relationship between amino acid sequence and molecule structure and function.