Equilibrium dialysis study on the interaction between Cu(Ⅱ) and HSA or BSA  

作　　者：LIANG Hong 1, XIN Bengang 1, WANG Xiujian 1, YUAN Yuzhou 1, ZHOU Yongqia 2 and SHEN Panwen 2 1. Department of Chemistry, Guangxi Normal University, Guilin 541004, China 2. Department of Chemistry, Nankai University, Tianjin 300071, China 

出　　处：《Chinese Science Bulletin》1998年第5期404-409,共6页

基　　金：ThisworkwassupportedbytheNationalNaturalScienceFoundationofChina (GrantNo .2 92 710 2 5 )andNaturalScienceFoundationofGuangxi.

摘　　要：The interaction of Cu(Ⅱ) and human serum albumin (HSA) or bovine serum albumin (BSA) at physiological pH is studied by equilibrium dialysis. The successive stability constants are obtained by non-linear least square methods fitting Bjerrum formula. For both the Cu(Ⅱ)-HSA and Cu(Ⅱ)-BSA systems, the order of magnitude of K 1 and K 2 was found to be ≈10 4 mol -1·dm 3. There are about twenty stoichiometry binding sites found in one HSA or BSA molecule. They can be divided into two or three sets. Results of equilibrium dialysis experiments suggest that there exists one strong metal binding site in both Cu(Ⅱ)-HSA and Cu(Ⅱ)-BSA. It is the imidazol group nitrogen atoms of His 3 that are primarily concerned with copper binding site. After reaching dialysis equilibrium, there is the interaction among the different binding sites, the values of K all deviate from the simple statistical effect except for K-1 and K-2 in both Cu(Ⅱ)-HSA and Cu(Ⅱ)-BSA systems, and the positive cooperative effect is found.The interaction of Cu(Ⅱ) and human serum albumin (HSA) or bovine serum albumin (BSA) at physiological pH is studied by equilibrium dialysis. The successive stability constants are obtained by non-linear least square methods fitting Bjerrum formula. For both the Cu(Ⅱ)-HSA and Cu(Ⅱ)-BSA systems, the order of magnitude of K 1 and K 2 was found to be ≈10 4 mol -1·dm 3. There are about twenty stoichiometry binding sites found in one HSA or BSA molecule. They can be divided into two or three sets. Results of equilibrium dialysis experiments suggest that there exists one strong metal binding site in both Cu(Ⅱ)-HSA and Cu(Ⅱ)-BSA. It is the imidazol group nitrogen atoms of His 3 that are primarily concerned with copper binding site. After reaching dialysis equilibrium, there is the interaction among the different binding sites, the values of K all deviate from the simple statistical effect except for K-1 and K-2 in both Cu(Ⅱ)-HSA and Cu(Ⅱ)-BSA systems, and the positive cooperative effect is found.

关 键 词：Cu(Ⅱ)-serum ALBUMIN equilibrium DIALYSIS atomic absorption SPECTROMETRY non-linear least square fitting. 

分 类 号：Q592.1[生物学—生物化学]