Figure 1.

t-BuOOH-dependent evolution of oxygen in wild-type, gpx-1Δ, gpx-2Δ, and tpxΔ mutant cells in the absence (A) or presence (B) of DCMU. Glycolaldehyde was added at 10 mm to the suspension of cells to inhibit CO₂ fixation. Light (1,000 μE m⁻² s⁻¹) was turned on and off, and t-BuOOH (70 μm) and DCMU (10 μm) were added to the suspension of cells at the times indicated by labeled arrows. The number in parentheses indicates the rate of t-BuOOH-dependent evolution of oxygen; the rate at 100% corresponds to 43.9 μmol O₂ evolved mg chlorophyll⁻¹ h⁻¹. The data are the mean value ± sd of three independent experiments.