FIGURE 7.

Decay kinetics of the P700⁺ flash-induced absorption change at 820. A, decay kinetics of 1 μm P700-F_X cores, 20 μm apo-PsaC, 20 μm PsaD, 0.04% (w/v) DM and filtrate (1) or retentate (2) from ultrafiltration of 42 μm holo-NfuA. The reconstitution mixture was incubated for 1 h, 10 μm DCPIP and 10 mm ascorbate were added prior to measurement. B, 1 μm P700-F_X cores, 20 μm apo-PsaC, 20 μm PsaD, 0.04% (w/v) DM and no addition (1), filtrate (2), or retentate (3) from ultrafiltration of chemically assembled Fe/S clusters. The reconstitution mixture was incubated for 1 h, 10 μm DCPIP and 10 mm ascorbate were added, and flash-induced kinetics at 820 nm were then measured. The discontinuity in the noise level is a consequence of fusing two kinetic traces taken at different time bases on the same laser flash.