FIGURE 3.

Light-induced hydroxyl radical formation in wt and PTOX⁺ thylakoids. Generation of hydroxyl radicals is shown by indirect spin trapping with 4-POBN/ethanol. Typical EPR spectra of the 4-POBN/α-hydroxyethyl adduct are shown. Samples were illuminated for 5 min at high light (1500 μmol quanta m⁻² s⁻¹). Where indicated, 10 μm DCMU was added prior to the illumination.