FIGURE 2.

Rapid bimolecular CO rebinding to Trp(E7) α and β subunits after laser photolysis. Concentrations of CO are listed beside each curve, and the lines represent fits to either a single exponential process with an offset or a two-exponential process with a second very slow phase. Experiments were conducted in 100 mm sodium phosphate, pH 7, 20 °C. A, time courses for ∼50 μm isolated Trp-58(E7) αCO. B, time courses for ∼50 μm isolated Trp-63(E7) βCO. Complete photolysis was achieved with a 0.5-μs excitation pulse from a Phase-R model 2100B dye laser.