Equilibrium dialysis of metal-serum albumin (Ⅱ)——Allosteric effect in Ni(Ⅱ)-serum albumin systems

• 作 者: 胡绪英 宋仲容 苏宪东 欧阳砥 黄杰生 周永洽
• 机 构: Department of Chemistry,Nankai University,Tianjin 300071,China,Department of Chemistry,Nankai Univer
• 出 处: Science in China(Series B)
• 发表日期: 1997年02期
• 关键词: dialysis albumin markedly fitting prior successive constants accordance bovine c

Detailed studies were carried out on equilibrium dialysis of the binding of Ni2++ ion to human scrum albumin (HSA) and bovine serum albumin (BSA).The successive stability constants were obtained by the Icfisi squares fitting.The eight binding sites found for both Ni(Ⅱ)-HSA and Ni(Ⅱ)-BSA systems can be divided into two different sets; and for both systems,there exist two identical prior binding sites where the bound Ni2+ ions can he con sidered as allosteric effectors,which induce the allosteric effect in accordance with the model proposed by Moeod et al As indicated by allosteric parameters,the ability of R-state to bind Ni2+ ions is ca 100 times as much as that of T state,and the conformation of HSA is markedly tenser than that of BSA.

Detailed studies were carried out on equilibrium dialysis of the binding of Ni2 ++ ion to human scrum albumin (HSA) and bovine serum albumin (BSA). The successive stability constants were obtained by the Icfisi squares fitting. The eight binding sites found for both nickel ( II) -HSA and Ni (II) -BSA systems can be divided into two different sets; and for both systems, there exist two identical prior binding sites where the bound Ni2 + ions can he con sidered as allosteric effectors, which induce the allosteric effect in accordance with the model proposed by Moeod et al As indicated by allosteric parameters, the ability of R-state to bind Ni2 + ions is ca 100 times as much as that of T state, and the conformation of HSA is markedly tenser than that of BSA .