Intrinsic Fluctuations in Transpiration Induce Photorespiration to Oxidize P700 in Photosystem I.

Upon exposure to environmental stress, the primary electron donor in photosystem I (PSI), P700, is oxidized to suppress the production of reactive oxygen species that could oxidatively inactivate the function of PSI. The illumination of rice leaves with actinic light induces intrinsic fluctuations in the opening and closing of stomata, causing the net CO assimilation rate to fluctuate. We examined the effects of these intrinsic fluctuations on electron transport reactions.