微过氧化物酶-8与Eu^(3+)相互作用的机理  

Interaction Mechanism Between Microperoxidase-8 and Eu^(3+)

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：《高等学校化学学报》2004年第5期892-895,共4页Chemical Journal of Chinese Universities

基　　金：国家自然科学基金 (批准号 :2 0 2 43 0 0 2);国家计划委员会稀土专项基金(批准号 :GJX0 110 0 62 6);江苏省科技厅高新技术基金(批准号 :BG2 0 0 10 45 );江苏省教育厅高校自然科学基金 批准号:0 1KJB15 0 0 0 6;2 0 0 0 L HZ0 0 0 0 SJ1;0 2 KJB15 0 0 0 6);国

摘　　要：用紫外 -可见 ( UV-Vis)吸收光谱和电化学方法研究 Eu3+ 与微过氧化物酶 -8( MP-8)相互作用的机理 ,发现 Eu3+优先与 MP-8中血红素基团的 2个丙酸基的羧基氧发生强的配位作用 ,导致 MP-8分子中血红素基团的非平面性、暴露程度和电化学可逆性的增加 .过剩的 Eu3+与 MP-8分子中肽链上的含氧基团发生弱的相互作用 。The interaction mechanism of microperoxidase-8 (MP-8) and Eu 3+ was determined by using UV-Vis absorption spectroscopic and electrochemical techniques. The study of the UV-Vis absorption spectra indicated that when Eu 3+ is added into the MP-8 solution, the Sored band shifts to the red direction and its absorbance decreases. The difference between the absorbance of the Soret band of the MP-8 solution without and with Eu 3+ increases linearly with increasing the molar ratio of Eu 3+ to MP-8 when the molar ratio is less than 3. When the molar ratio is larger than 3, the difference decreases with increasing the molar ratio. Their extension lines intersect at the molar ratio of 2. The electrochemical study showed that after MP-8 was added into the Eu 3+ solution with the molar ratio of 10, the area of the anodic or cathodic peak of Eu 3+ decreases about 20% comparing with that before adding MP-8. All the UV-Vis absorption spectroscopic and elelctrochemical results illustrated that Eu 3+ ions would coordinate strongly with carboxy oxygen of two propionic acid groups of the heme group in an MP-8 molecule, leading to an increase in the non-planarity of the porphyrin ring, greater exposure degree of the heme group, and better reversibility of the electrochemical reaction of the MP-8 molecule. The excessive Eu 3+ ions weakly interact with the oxygen-contained groups in the peptide chain, resulting in a slight alteration of the structure of the prophyrin group.

关 键 词：微过氧化物酶-8 銪 相互作用 配位作用 血红素基团 稀土 微量元素肥料 紫外-可见吸收光谱 循环伏安法 

分 类 号：Q554.6[生物学—生物化学] S143.72[农业科学—肥料学]