FIG. 4.

Effect of GT on NADPH consumption. HTG-solubilized membranes (1.5 pmol of heme equivalent) and cytosol (100 μg) were incubated in the absence (a and b) or presence (c and d) of 92 nmol of GT for 3 min in 0.1 ml of activation buffer (see Materials and Methods) before a 5-min stimulation with 36 nmol of MA. The mixture was then transferred at the point indicated by the arrow to a cuvette preset in the spectrophotometer containing NADPH (final concentration, 0.125 mM) in the activation buffer. A decrease in the absorbance at 340 nm indicates NADPH consumption.