ZHANG Chun-hua WU Ze-ying JU Ting GE Ying. Purification and Identification of Glutathione S-transferase in Rice Root under Cadmium Stress. Rice Science 2013 20(1): −

Abstract

Cadmium (Cd) contamination in paddy soils poses a serious threat to the production and quality of rice. Among various biochemical processes related to Cd detoxification in rice glutathione S-transferase (GST) plays an important role catalyzing Cd complexation with glutathione (GSH) and scavenging reactive oxygen species (ROS) in cell. However the identification of GST isozymes alleviating Cd stress has not yet received much attention. In this study a hydroponic experiment was conducted to investigate the response of GST isozymes in rice roots upon Cd exposure. Results showed that rice root GST activity was clearly enhanced by 50 μmol-L Cd treatment for 7 d. The GST isozymes were purified by ammonium sulphate precipitation gel filtration chromatography and affinity chromatography. After being separated by SDS-PAGE and visualized by silver staining GSTU6 was identified by in-gel digestion MALDI-TOF-MS analysis and peptide mass fingerprint. The results confirm the vital function of tau class rice GST in Cd detoxification.