FIGURE 4.

Dependence of ferredoxin reduction on NADH (A) and ferredoxin (B). Enzyme activity was measured in assay buffer (buffer B) containing the caffeyl-CoA regeneration system (200 units of the CoA transferase CarA and 0.2 mm caffeate), 8 μg of protein, and 5 μm caffeyl-CoA. All assays were done at 30 °C under an atmosphere of 100% nitrogen. For NADH dependence (A), NADH was added, and the reaction was started by the addition of 20 μm ferredoxin. For ferredoxin dependence (B), 0.5 mm NADH was added, and the reaction was started by the addition of ferredoxin.