Isoelectric focusing of glutathione S-transferases: comparison of the acidic transferases from human liver, kidney, lung, spleen and placenta.

The glutathione S-transferase composition of human liver, kidney, lung, spleen and placenta was studied by density gradient isoelectric focusing. On the basis of the enzyme distribution it was possible to divide the supernatants into two groups: one having a predominance of basic activity, the other acidic. Each supernatant consisted of more than one transferase. Human liver and kidney, two major detoxifying organs in the body, bore a clear predominance of basic enzymes and they had the highest transferase activities. The activity of the other organs consisted of almost only a single acidic transferase. Properties of the major acidic transferases from the organs were compared. Prior to the studies the enzymes underwent partial two-step purification. According to the comparison it seems evident that the major acidic transferases from human kidney, lung, spleen and placenta are either closely related or identical.