蛋白质沉淀剂对杨小舟蛾谷胱甘肽S-转移酶的部分纯化

Partial purification of glutathione S-transferases by protein precipitators in Micromelalopha troglodyta(Lepidoptera:Notodontidae)

用硫酸铵和聚乙二醇（PEG）沉淀技术对杨小舟蛾幼虫谷胱甘肽S-转移酶（GSTs）进行了纯化研究。结果表明：通过硫酸铵沉淀，杨小舟蛾GSTs活性主要分布在40％～60％沉淀段，比活力为174．41nmol／（min·mg），纯化倍数为1．39。在5种PEG（PEG400、PEG2000、PEG4000、PEG6000和PEG20000）中，PEG20000的纯化效果最好。杨小舟蛾PEG20000沉淀的GSTs活性峰主要分布在10％～15％沉淀段，GSTs比活力＆454．14nmol／（min·mg），纯化倍数达到15．50。因而，PEG20000沉淀对于杨小舟蛾幼虫GSTs的纯化效果优于硫酸铵。

The partial purification of glutathione S-transferases （GSTs） in the larvae of Micromelalopha troglodyta was stud- ied using ammonium sulfate fractionation and polyethyleneglycol （PEG） fractionation. The results showed that the peak of GST activity was in 40% -60% of ammonium sulfate fraetionation, and the specific activity was 174.41 nmol/（ min·mg）, and the purification factor was 1.39 fold. The efficacy of purification by PEG20000 was the best in five kinds of PEG tested. By the PEG20000 fractionation, the activity peak of GSTs was in 10% - 15%, the specific activity was 454.14 nmol/（min·mg）, and purification factor was 15.50 fold. Therefore, the efficacy of GST purification by PEG20000 was better than that of ammonium sulfate fraetionation in M. troglodyta.