镉胁迫下水稻根部谷胱甘肽硫转移酶的纯化和鉴定

admium pollution in paddy soils poses a serious threat to the production and quality of rice. In this paper, a hydroponic experiment was conducted to investigate the role of glutathione S-transferase (GST) in Cd resistance in rice. The activity of rice GST under Cd stress was determined. In addition, GST in rice root was seperated, purified and identified. Results showed that rice root GST was significantly induced by 50μM Cd. The enzyme was purified by following steps: ammonium sulphate precipitation, desalting, gel filtration chromatography, affinity chromatography and SDS-PAGE. After in-gel digestion, MALDI-TOF-MS analysis, peptide mass fingerprint and comparison with the protein database, a GST isozyme, GSTU6, was identified. The results suggest that the tau subclass GST plays an important role in Cd detoxification in rice.