Evidence for the occurrence of selenium-independent glutathione peroxidase activity in rat liver microsomes

Center for Air Environment Studies The Pennsylvania State University University Park, PA 16802 USA; Department of Biochemistry The Pennsylvania State University University Park, PA 16802 USA; Department of Veterinary Science The Pennsylvania State University University Park, PA 16802 USA
Biochemical and Biophysical Research Communications (Impact Factor: 2.28). 09/1981; DOI: 10.1016/0006-291X(81)91844-1

ABSTRACT Rat liver microsomes exhibit selenium-independent glutathione peroxidase activity which is associated with glutathione S-transferase activity. The peroxidase activity is not due to contamination with either soluble selenium-dependent or selenium-independent glutathione peroxidase activities of the cytosol. N-Ethylmaleimide treatment which stimulates rat liver microsomal glutathione transferase activity concomitantly stimulates the glutathione peroxidase activity. In contrast, N-ethylmaleimide depresses both enzyme activities of the cytosol. A protein exhibiting both glutathione peroxidase and glutathione transferase activity was isolated from the microsomes and purified to homogeneity by DEAE cellulose ion-exchange and S-hexylglutathione Sepharose 6B affinity chromatography.

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