A comparison of the glutathione S-transferases of trout and rat liver.

1. Cytosol from trout liver, gills and intestinal caeca has substantial glutathione S-transferase activity. 2. Gel-exclusion and ion-exchange chromatography suggest that trout liver has several glutathione S-transferases with different molecular weights and ionic charges. 3. A component capable of binding lithocholic acid eluted together with glutathione S-transferase activity. Some of the transferase activity did not elute together with binding activity. 4. The enzymic activity from trout liver was less stable at 37 degrees C than that from rat liver. 5. The glutathione S-transferases of fish liver have a similar specific activity to those of rat liver but different molecular properties.