1. Four different rat glutathione S-transferase (GST) isoenzymes, belonging to three different classes, were examined for their GSH conjugating capacity towards 11 2-substituted 1- chloro-4-nitrobenzene derivatives. Significant differences were found in their enzyme kinetic parameters K m, k cat and k cat/K m. 2. Substrates with bulky substituents on the ortho- position appeared to have high affinities (low K m's) for the active site of the GST- ...
