Inhibition of mouse DHODH (amino acid residues 30 to 396) expressed in Escherichia coli BL21 cells assessed as orotic acid production using dihydroorotate as substrate by DCIP dye-based assay
Inhibition of N-terminal His6-tagged recombinant Plasmodium falciparum DHODH (amino acid residues 158 to 569) expressed in Escherichia coli BL21 cells assessed as orotic acid production using dihydroorotate as substrate by DCIP dye-based assay
Inhibition of C-terminal His6-tagged human DHODH (amino acid residues 30 to 396) expressed in Escherichia coli BL21 cells assessed as orotic acid production using dihydroorotate as substrate by DCIP dye-based assay
Inhibition of rat DHODH (amino acid residues 30 to 396) expressed in Escherichia coli BL21 cells assessed as orotic acid production using dihydroorotate as substrate by DCIP dye-based assay
Inhibition of dog DHODH (amino acid residues 48 to 414) expressed in Escherichia coli BL21 cells assessed as orotic acid production using dihydroorotate as substrate by DCIP dye-based assay
Inhibition of C-terminal His6-tagged human DHODH (amino acid residues 30 to 396) expressed in Escherichia coli BL21 cells assessed as orotic acid production using dihydroorotate as substrate by direct assay in presence of oxygen depleting system
Inhibition of C-terminal His6-tagged human DHODH (amino acid residues 30 to 396) L46A mutant expressed in Escherichia coli BL21 cells assessed as orotic acid production using dihydroorotate as substrate by direct assay in presence of oxygen depleting system
Inhibition of C-terminal His6-tagged human DHODH (amino acid residues 30 to 396) H56A mutant expressed in Escherichia coli BL21 cells assessed as orotic acid production using dihydroorotate as substrate by direct assay in presence of oxygen depleting system
Inhibition of C-terminal His6-tagged human DHODH (amino acid residues 30 to 396) R136A mutant expressed in Escherichia coli BL21 cells assessed as orotic acid production using dihydroorotate as substrate by direct assay in presence of oxygen depleting system
Inhibition of C-terminal His6-tagged human DHODH (amino acid residues 30 to 396) L359A mutant expressed in Escherichia coli BL21 cells assessed as orotic acid production using dihydroorotate as substrate by direct assay in presence of oxygen depleting system
Inhibiton Assay: For studying inhibition of Plasmodium or human DHODH enzyme, two assays that are in routine use are described, for example, in Baldwin, et al. (2002) JBiol Chem., 277, 41827-41834, and Baldwin, et al. (2005) J. Biol. Chem., 280. 21847-21853.Briefly, this colorimetric assay monitors the reduction of 2,6-dichloroindophenol (DCIP) at 600 nm (e = 18.8 mM-1cm-1) for measuring DHOD inhibition. The assay was carried out using a solution containing 100 mM HEPES, pH 8.0, 150 mM NaCl, 10% glycerol, 0.1% Triton X-100, 20 micro molar CoQD (coenzyme QD), 200 micro molar L-dihydroorotate, and 120 micro molar DCIP. Reactions are initiated by addition of enzyme to a final concentration in the range of about 5 nM to about 50 nM while maintaining the temperature of a circulating water bath at 25° C. Alternatively, for potent compounds, activity was determined by directly measuring the production of orotic acid at 296 nm (ε = 4.3 mM-1 cm-1).