Figure 3
Inhibitory kinetics of bc1 complex.
(A) Chemical structures of AZ (azoxystrobin) and its analogues, compound 1 and compound 18. These compounds have a common pharmacophore structure: methoxyacrylate (MOA). (B) AZ is a competitive inhibitor with respect to substrate DBH2. Each reaction mixture contains phosphate buffered saline (PBS; 100 mM, pH 6.5), ethylenediaminetetraacetic acid (EDTA; 2 mM), lauryl maltoside (750 μM), oxidised cytochrome c (100 μM), SCR (0.05 nM), DBH2 (20–120 μM) and a specified amount of AZ (1, 0 nM; 2, 500 nM; 3, 1000 nM; 4, 2000 nM; 5, 3000 nM; and 6, 5000 nM). (C) Compound 1 is non-competitive with respect to cytochrome c. The reaction mixture contains 100 mM, pH 7.4), EDTA (0.3 mM), succinate (20 mM), SCR (0.1 nM), cytochrome c (1.13–15.6 μM) and a series of concentrations of compound 1 (1, 0 nM; 2, 10 nM; 3, 20 nM; 4, 40 nM; and 5, 60 nM). (D) Compound 1 is competitive with respect to DBH2. Each reaction mixture contains 100 mM, pH 6.5), EDTA (2 mM), lauryl maltoside (750 μM), oxidised cytochrome c (100 μM), SCR (0.05 nM), DBH2 (20–120 μM) and a specified amount of compound 1 (1, 0 nM; 2, 50 nM; 3, 100 nM; 4, 200 nM; 5, 300 nM; and 6, 500 nM).
