Li T Y, Minkel D T, Shaw C F, Petering D H
Biochem J. 1981 Feb 1;193(2):441-6. doi: 10.1042/bj1930441.
Rat liver and horse kidney metallothioneins react with 5,5'-dithiobis-(2-nitrobenzoic acid) (Nbs2) to release 5-thio-2-nitrobenzoate and metal ions. The reactions are slow and exhibit biphasic kinetics with each process having an empirical rate law of the form: rate - k[RSM] X [Nbs2] + k'[RSM], where RSM represents mental-bound thiolate groups. The pseudo-first-order rates are insensitive to pH but are modified in guanidine hydrochloride solution. Rat liver metallothioneins of variable zinc, copper and cadmium composition react similarly and give observable thiol/total metal ratios in good agreement with stoichiometries of SH/(Cd + Zn) of 3 and SH/Cu of 1. A model complex cadmium-2,3-dimercaptopropanol, resembles the proteins in its reaction with Nbs2.
大鼠肝脏和马肾脏的金属硫蛋白与5,5'-二硫代双（2-硝基苯甲酸）（Nbs2）反应，释放出5-硫代-2-硝基苯甲酸酯和金属离子。反应缓慢，呈现双相动力学，每个过程都有一个经验速率定律，形式为：速率 = k[RSM]×[Nbs2] + k'[RSM]，其中RSM代表金属结合的硫醇盐基团。准一级反应速率对pH不敏感，但在盐酸胍溶液中会发生改变。锌、铜和镉组成不同的大鼠肝脏金属硫蛋白反应类似，得到的可观察到的硫醇/总金属比率与SH/(Cd + Zn)为3和SH/Cu为1的化学计量比非常吻合。一种模型配合物镉-2,3-二巯基丙醇在与Nbs2的反应中与蛋白质相似。
