大连理工大学学报Issue(1)：20-27,8.DOI:10.7511/dllgxb201401004
多种肌红蛋白突变体与Cu（Ⅱ）相互作用机制光谱法研究
Investigation on mechanism of interaction between Cu (Ⅱ) and multifold mutants of myoglobin by spectroscopic techniques
摘要
Abstract
The interaction between Cu(Ⅱ) and the mutant proteins (D44K ,D60K and K56D) which are attained by PCR site-directed mutagenesis is investigated by multi-spectroscopic techniques .The results show that the fluorescence of all the Mbs is quenched regularly with the addition of Cu (Ⅱ ) . The quenching belongs to the static fluorescence quenching .But the binding constants ,the numbers of the binding sites , the thermodynamic parameters , the binding distance and three-dimensional conformation of mutants are different from wild type .At the same temperature ,the sequence for binding strength is Mb(WT)< Mb(D60K)< Mb(K56D)< Mb(D44K) ,the electrostatic interaction and hydrophobic power play dominating roles in the course of binding .The binding distance sequence is Mb(WT)<Mb(K56D)<Mb(D60K)<Mb(D44K) .The effects of Cu(Ⅱ) on conformation of Mb and mutants are further analyzed by multi-spectroscopic techniques .T he experimental results indicate that the mutants of Mb become easier to interact with Cu (Ⅱ ) ,and α-helix content of the mutants decreases more after interaction with Cu (Ⅱ ) .In all ,mutation in surface-charged residue Asp44 , Asp60 and Lys56 has an effect on the conformation and function of myoglobin .关键词
肌红蛋白/突变体(D44K/D60K/K56D)/Cu(Ⅱ)/相互作用/光谱法Key words
myoglobin/mutants (D44K/D60K/K56D)/Cu(Ⅱ)/interaction/spectroscopic techniques分类
化学化工引用本文复制引用
唐乾,张越,曹洪玉,马静,郑学仿,王静云..多种肌红蛋白突变体与Cu（Ⅱ）相互作用机制光谱法研究[J].大连理工大学学报,2014,(1):20-27,8.基金项目
国家自然科学基金资助项目（21271036）；辽宁省教育厅资助项目（L2013470）． （）
