Department of Biology, Faculty of Arts and Sciences, University of Çukurova, 01330 Adana, Turkey.
Environ Toxicol Pharmacol. 2007 Jan;23(1):33-8. doi: 10.1016/j.etap.2006.06.002. Epub 2006 Jun 15.
Freshwater fish Oreochromis niloticus were exposed individually to 1mg/L concentrations of cadmium and zinc for 14 days at 20, 25 and 30°C. Heat-treated (80°C) liver tissue homogenates were run on a column packed with Sephadex G-75 to obtain eluats for determination of metallothionein-like proteins, sulfhydryl groups and metal concentrations. Elution profiles of the liver showed that there were three heat-resistant protein peaks detected at 254 and 280nm in all samples. Approximate molecular weights of proteins obtained from the first, second and third peaks were 70,000, 43,000 and 6500Da, respectively. Metallothionein-like proteins (6500) of control fish contained sulfhydryl groups and zinc, but not cadmium. Concentrations of zinc and cadmium in MT-like proteins increased in metal exposed fish and these increases were temperature dependent. However, zinc concentration in control fish decreased in relation to temperature increase. Data indicated that temperature plays significant role on metals bound on metallothioneins. This suggests that season of sampling should be taken into account when natural monitoring studies are carried out with metallothioneins.
淡水鱼奥利亚罗非鱼在 20、25 和 30°C 下分别暴露于 1mg/L 的镉和锌浓度中 14 天。将热处理（80°C）的肝组织匀浆在填充有 Sephadex G-75 的柱上运行，以获得用于测定金属硫蛋白样蛋白、巯基和金属浓度的洗脱物。肝洗脱曲线显示，所有样品在 254nm 和 280nm 处均检测到三个耐热蛋白峰。从第一个、第二个和第三个峰获得的蛋白质的近似分子量分别为 70,000、43,000 和 6,500Da。对照鱼的金属硫蛋白样蛋白（6500）含有巯基和锌，但不含镉。暴露于金属的鱼中的金属硫蛋白样蛋白中的锌和镉浓度增加，并且这些增加与温度有关。然而，对照鱼中的锌浓度随着温度的升高而降低。数据表明，温度对金属与金属硫蛋白结合有重要影响。这表明在进行金属硫蛋白的自然监测研究时，应考虑采样的季节。
