Uranyl-cytochrome b_5 interaction regulated by surface mutations and cytochrome c

作     者：孙美慧 杜可杰 聂长明 文格波 林英武 SUN Mei-Hui;DU Ke-Jie;NIE Chang-Ming;WEN Ge-bo;LIN Ying-Wu

作者机构：School of Chemistry and Chemical Engineering University of South China Laboratory of Protein Structure and Function University of South China 

出 版 物：《Nuclear Science and Techniques》 (核技术（英文）)

年 卷 期：2015年第26卷第5期

页      面：44-47页

核心收录：

学科分类：0710[理学-生物学] 071010[理学-生物化学与分子生物学] 081704[工学-应用化学] 07[理学] 08[工学] 0817[工学-化学工程与技术] 

基　　金：Supported by National Natural Science Foundation of China(Nos.21101091 and 11275090) 

主　　题：蛋白质相互作用 细胞色素b5 细胞色素C 铀酰离子 突变体 表面 蛋白质复合物 毒性机理 

摘      要：Understanding uranium-protein interaction is important for revealing the mechanism of uranyl ion(UO2+2)toxicity. In this study, we investigated the interaction between UO2+2and a quadruple mutant of cytochrome b5(E44/48/56A/D60 A cyt b5, namely 4A cyt b5) by spectroscopic approaches. The four mutated negativelycharged surface residues of cyt b5 have been considered to be the interactive sites with cytochrome c(cyt c).Also, we studied the interaction between UO2+2and the protein-protein complex of 4A cyt b5-cyt c. The results were compared to the interaction between UO2+2and cyt b5, and the interaction between cyt c and cyt b5-cyt c complex, from previous studies. It was found that the interaction of UO2+2-cyt b5, i.e., uranyl ion binding to cyt b5 surface at Glu37 and Glu43 as previously proposed by molecular modeling, is regulated by both surface mutations of cyt b5 and its interacting protein partner cyt c. These provide valuable information on metal-protein-protein interactions and clues for understanding the mechanism of uranyl toxicity.