金属硫蛋白的诱导和分离

Induction and Isolation of Metallothioprotein

经皮下和腹腔注射CdCl_2后,肝肾匀浆25000r/min,140min离心,上清液通过SephadexG75凝胶层析分离。得到样品再经DEAE-A25离子交换柱层析,NaCl梯度洗脱。应用紫外分光光度计和原子吸收仪测定分离样品。结果初步凝胶层析在诱导组获得250nm特征吸收峰,且Cd含量亦在此峰显著增高。而对照组未见此峰出现。进一步通过DEAE-A25离子交换柱层析将其纯化分离成为镉结合蛋白1和镉合蛋白2两种亚类形式。

This paper reports the result of inducing and isolating of rat metallothionein(MT). Rats were given repeated injections of CdCl_2. The homogenized mixture of the livers and kidneys centrifuged at 25000r/min for 140min. The supernatants were isolated by Sephadex G 75 column. The used fractions were then separated by DEAE-A25 ion-exchange chromatography. The all fractions were analysed by using ultraviolet photelometer and atomic absorption spectroscopy. The result shows that 250 nm specific absorption peak was discovered through G75 chromatography in the inducing group. At the sametime Cd concentration increased in the peak. It was not seen in contrast group. Further purefication on DEAE-A25 column showed two main protein peaks, Cd-Bp_1 and Cd-Bp_z. Several characteristics were similar to those of the earlier de- scribed MT.