【摘要】 用氯化镉诱导鲫鱼(Carassius aurattus),应用层析介质 Sephacryl S 体系从鱼肝脏中提取金属硫蛋白(MT),并对其性质进行研究.实验表明鲫鱼 MT 的性质与哺乳动物 MT 的性质十分相似.分子量约10 000,含丰富的半胱氨酸,较多的赖氨酸,不含芳香族氨基酸.紫外250nm 处强吸收,280nm 处几乎没有吸收。鱼 MT 含7个金属每分子,并含有20个巯基.测得鲫鱼 MT 等电点 pI 在5.6左右.更多还原

【Abstract】 The metallothionein(MT)was purified from the liver of Carassius auratus induced by exposure tocadmium chloride and characterized.It shows very similar to mammalian metallothioneins in all of itsproperties.The MT of the fish contains high cysteine contents(30%)and with an absence of aromaticacid residues.The thiol groups of the cysteine residues combine with the cadmium in SH/Cd molar ratioof 3∶1 and produce a characteristic absorption maxium at 250 nm,minimum at 280 nm.The metalanalyses reveal only traces of zinc and copper in addition to cadmium.The molecular weight is deter-mined to be about 10 000 by gel filtration on HPLC and SDS-PAGE method.The isoelectric point offish MT is demonstrated to be about 5.6.更多还原