Abstract: The giant salamander is very interesting animal from evolutionary point of view,because its transitional position from aquatic to terrestrial life, therefore, the present investigation dealing with the metallothionein (MT) molecular evolution of the giant salamander provides significant clues to evolution of vertebrate. Each extract of liver and intestine of giant salamander induced by subcutaneous injection of cadmium (CdCl₂) was separated by gel filtration chromatography Sephadex G-50 column,then was separated into twoisometallothioneins (isoMTs) by ion-exchange chromatography DEAE Sepharose Fast Flow column. According to the results of gel filtration HPLC detection, the molecular weight of the two isoMTs was about 12000 dalton. The isoMTs contained Cd and Zn (cadmium and zinc) and the value of Cd/Zn was about 3/1. The Cys content was about 21%～24% and the product amount were about 628μg·MT/g·wet liver, 185μg·MT/g·wet intestine. The isoMTs have the typical amino acid composition of metallothionein and U.V. absorption shoulder near 250 nm.

Key words: metallothionein, giant salamander, isolation and purification

摘要： 以两栖动物大鲵为材料，镉诱导金属硫蛋白(MT)合成，凝胶过滤Sephadex G-50及弱阴离子交换 DEAE Sepharose Fast Flow常压液相柱层析进行两次分离纯化肝脏及肠材料，分别得到两个MT亚型，凝胶过滤表观分子量约12kD，半胱氨酸含量约21%～24%，主要含Cd与Zn,Cd/Zn约为3/1，肝MT产率为628μg MT/g鲜重肝，肠 MT产率为185μgMT/g鲜重肠，250nm附近均具有紫外吸收肩。

关键词: 金属硫蛋白, 大鲵, 分离纯化, 分析鉴定