猴金属硫蛋白MT1 α-结构域中Cys33和Cys34的突变对蛋白质稳定性的影响  

Effect of Mutation of Cys33 and Cys34 in the α-Domain of Monkey Metallothionein-1 on the Protein Stability

作　　者：余文浩[1] 蔡斌[1] 高原[1] 陈东[1] 黄仲贤[1] 

机构地区：[1]复旦大学化学系化学生物学实验室,上海200433

出　　处：《高等学校化学学报》2003年第4期569-575,共7页Chemical Journal of Chinese Universities

基　　金：国家自然科学基金 (批准号 :39990 60 0 )

摘　　要：重组猴金属硫蛋白 MT1及其 C3 3 M,C3 4S和 C3 3 M/ C3 4S突变体蛋白的蛋白质快速液相色谱( FPLC)分析表明 ,突变体蛋白 C3 4S和 C3 3 M/ C3 4S存在着两个稳定的流分 f1和 f2 .CD光谱和重金属离子分析表明 ,突变体蛋白多流分不仅与半胱氨酸和 Cd2 + 离子结合方式和构型有关 ,还与金属结合量有关 .突变体蛋白多流分的结果表明 ,在把猴金属硫蛋白 α-结构域中的 Cys3 3和 Cys3 4突变为非半胱氨酸残基以建立 β-β结构域的金属硫蛋白时 ,可导致蛋白形成多种结构形式 .这表明 α-结构域在稳定金属硫蛋白的结构中起着重要的作用 。FPLC analysis of the recombinant protein of monkey metallothionein, MT1 and its C33M, C34S and C33M/C34S mutants shows that there were two stable components, f1 and f2. CD study and metal ion analyses indicate that multi components of the mutants relates not only to the binding mode and configuration between cysteins and cadmiun ions, but also to the number of the metal ions. This result also demonstrates that when the Cys33 and Cys34 of α domain of monkey metallothion were mutated into non cystein residues in an attempt of creating a metallothionein with β β domain structure, it led to a protein with multiple structures. It indicates that the α domain plays an important role in the protein stability, and also the distribution of cystein residues affects the formation of metal thiolate clusters and the tertiary structure of the protein significantly.

关 键 词：金属硫蛋白MT1α-结构域 Cys33 Cys34 蛋白质 稳定性 突变体 圆二色谱 电喷雾质谱 半胱氨酸 结构 

分 类 号：Q513[生物学—生物化学]