Glutathione S-transferase π in an arsenic-resistant Chinese hamster ovary cell line

J. F. Lo, H. F. Wang, M. F. Tam, T. C. Lee*

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review

57 Scopus citations


A glutathione S-transferase (GST) was purified from an arsenic-resistant Chinese hamster ovary cell line, SA7. The SA7 GST was shown to catalyse the conjugation of glutathione and ethacrynic acid, a specific substrate for Pi class GST. Its N-terminal amino-acid sequence has 80% identical residues to that of rat GST P and human GSTπ. Thus, the GST purified from SA7 cells belongs to the Pi family. Treatment with Cibacron Blue or ethacrynic acid, which are GST inhibitors, significantly decreased the resistance of SA7 cells to sodium arsenite. On the other hand, pretreatment of SA7N cells, a partial revertant of SA7 cells, with sublethal doses of sodium arsenite, cadmium acetate or zinc sulphate resulted in re-elevation of GST activities and the cells regained the arsenic resistance. The regained arsenic resistance was well correlated with the levels of GSTπ which were induced dose-dependently by zinc sulphate. Heat-shock treatment (45°C for 10 min) did not increase GSTπ expression or arsenic resistance of SA7N cells. The results indicate that GSTπ is possibly involved in the mechanism of arsenic detoxification.

Original languageEnglish
Pages (from-to)977-982
Number of pages6
JournalBiochemical Journal
Issue number3
StatePublished - 1992


Dive into the research topics of 'Glutathione S-transferase π in an arsenic-resistant Chinese hamster ovary cell line'. Together they form a unique fingerprint.

Cite this