FIG. 5.

DCCD inhibition of quinone reduction by NDH-1. Aliquots of NDH-1 obtained by PEG precipitation (0.3 mg in 50 μl 50 mM HEPES-KOH, pH 7.5, 50 mM KCl, and 4% glycerol) were incubated with 0, 100, 200, or 500 μM DCCD for 4 min, and the quinone reductase activity was monitored at pH 8.0.