Effects of some drugs on human erythrocyte 6-phosphogluconate dehydrogenase: an in vitro study

Inhibitory effects of some drugs were investigated on human erythrocyte 6-phosphogluconate dehydrogenase obtained with a 6552-fold purification in a yield of 78% using 2', 5'-ADP Separose 4B affinity gel. Which on SDS polyacrylamide gel electrophoresis showed a single band. Larnoxicam, metronidazole, imipenem, ornidazole, vancomycin, clindamycin, and amoxicillin exhibited inhibitory effects on the enzyme in vitro with IC50 values of 0.17, 0.23, 0.43, 21.79, 46.39, 117.43 and 287.35 mM, and the Ki constants 0.40 +/- 0.04, 0.57 +/- 0.06, 0.77 +/- 0.11, 42.40 +/- 2.89, 65.60 +/- 4.03, 130.22 +/- 9.21, and 287.58 +/- 10.56 mM, respectively. While vancomycin, clindamycin and amoxicillin showed competitive inhibition the other drugs displayed noncompetitive inhibition.