Inhibition of ferricyanide reduction in chloroplast particles by anaerobicity.

The reduction of ferricyanide by spinach and pea chloroplast particles was the same under aerobic or anaerobic conditions. The rate of ferricyanide reduction by these particles uncoupled by ammonium chloride or carboxycyanide p-trifluoromethoxyhydrazone, or $\text{Chlamydomonas reinhardi}$ or $\text{Euglena gracilis}$ particles uncoupled by sonic oscillation, was inhibited by anaerobic conditions. This inhibition by anaerobicity may explain the cessation of the photolysis of water as measured by H₂ production in reconstituted preparations consisting of chloroplast particles, ferredoxin and fully active hydrogenase.