Cu^(2+)胁迫条件对涡虫体内过氧化氢酶活性的影响

Influence of Cu^(2+) on the Activity of Dugesia japonia Catalase

实验以0 .2 5、0 .5、1.0、2 .0mg·kg- 1 4种质量浓度的CuSO4 溶液培养东亚三角头涡虫(Dugesiajaponia) 4 8h后,提取其体内蛋白质并测定其过氧化氢酶(CAT)的活性。测定结果:涡虫体内蛋白的CAT酶活性依次为12 .5 9、2 3.74、18.37、18.72ū·mg- 1 。以自来水(实验室常规培养方法)为对照,其相应的酶活性为18.78ū·ｍｇ- 1 。实验结果表明:低浓度下Cu2 + 刺激CAT酶活性增加,而在高浓度下,由于涡虫耐受力的存在而使涡虫的CAT酶活性维持在正常水平(与对照组差异不大)。当Cu2 + 浓度达到4mg·kg- 1 时所培养的涡虫不到2 4h全部死亡。

Dugesia japonia was trained for 48 hs with CuSO 4 solutions of 0.25mg·kg -1 , 0.5mg·kg -1 , 1.0 mg·kg -1 and 2.0 mg·kg -1 respectively. Its internal protein was extracted and the activity of catalase (CAT) was determined. The enzyme activities were 12.59 u/mg, 23.74 u/mg, 18.37 u/mg and 18.72 ud/mg. The enzyme activity was 18.78 u/mg When trained with tap water(the control). The result showed that Cu 2+ stimulated the activity at lower concentrations, but made the activity maintain the normal level at high concentration because of tolerance. Dugesia japonia died off within 24h when Cu 2+ concentration was up to 4 mg·kg -1 .