IC50 values of the most potent inhibitors of EcaGST A3-3.

Activities were tested with the alternative substrates CDNB (1 mM, in 100 mM sodium phosphate buffer) and Δ5-AD (0.1 mM, in 25 mM sodium phosphate buffer) in the presence of 1 mM GSH at 30°C. Inhibitor concentrations varied between 0.029 μM and 15 μM at pH 6.5 (for CDNB) and between 0.0037 μM and 15 μM at pH 8.0 (for Δ5-AD). The four most potent inhibitors with either substrate are highlighted. With some inhibitors high absorbance or other physical factors gave anomalous values.