La^(3+)或Eu^(3+)与微过氧化物酶-8相互作用强弱的研究  

Study on the Interaction Strength of La^(3+) or Eu^(3+) with Microperoxidase-8

作　　者：陈婷婷[1] 黄晓华[1] 杜江燕[1] 冯玉英[1] 刘长鹏[2] 邢巍[2] 陆天虹[1] 

机构地区：[1]南京师范大学化学与环境科学学院,南京210097 [2]中国科学院长春应用化学研究所,长春130022

出　　处：《物理化学学报》2004年第8期887-891,共5页Acta Physico-Chimica Sinica

基　　金：国家自然科学基金(20243002);国家计委稀土专项基金(GJX01100626);江苏省科技厅高新技术基金(BG2001045);江苏省教育厅高校自然科学基金(01KJB150006;2000LHZ0000SJ1;02KJB150006);国家"211"工程重点学科建设资助项目~~

摘　　要：研究了La3+或Eu3+与微过氧化酶-8(MP-8)相互作用并比较了它们与MP-8相互作用的强弱.紫外-可见(UV-Vis)吸收光谱和电化学的结果表明,不论在不含NaCl或含NaCl的溶液中,一个La3+或Eu3+优先与MP-8分子中血红素上两个丙酸基中的羧基氧发生强的键合作用,而过量的La3+或Eu3+与肽链上的羰基氧发生弱的相互作用.实验结果还清楚地证明Eu3+与MP-8的相互作用要强于La3+与MP-8的相互作用.The interaction of La3+ or Eu3+ with MP-8 was studied and the interaction strength of La3+ or Eu3+ with MP-8 was compared. Comparing with the UV-Vis absorption spectrum of the MP-8 solution without La3+ or Eu3+, the position of the Soret band for the MP-8 solution with La3+ or Eu3+ shifts to the red direction and the absorbance decreases. The extents of the red shift of the band position and the decrease in the absorbance for Eu3+ in the solutions without or with NaCl are larger than that for La3+. In 0.10 mol . L-1 NaCl solution, Le(3+) or Eu3+ could completely coordinate with carboxylate oxygen of two propionic acid groups of the heme group in an MP-8 molecule when the molar ratio of La3+ or Eu3+ and MP-8 is 10 and 5, respectively. In addition, the cyclic voltammetric results showed that the redox peak area of Eu3+ decreased 20% after adding MP-8 into the solution. These results clearly illustrated that one La3+ or Eu3+ ion would coordinate strongly with carboxylate oxygen of two propionic acid groups of the heme group in an MP-8 molecule and the excessive La3+ or Eu3+ ions weakly interact with the-carboxylate oxygen in the peptide chain. The interaction between Eu3+ and MP-8 is stronger than that between La3+ and MP-8.

关 键 词：微过氧化物酶-8 LA^3+ EU^3+ 紫外-可见吸收光谱 电化学 

分 类 号：O621[理学—有机化学]