TY - JOUR TI - Limitations to photosynthesis by proton motive force-induced photosystem II photodamage AU - Davis, Geoffry A AU - Kanazawa, Atsuko AU - Schöttler, Mark Aurel AU - Kohzuma, Kaori AU - Froehlich, John E AU - Rutherford, A William AU - Satoh-Cruz, Mio AU - Minhas, Deepika AU - Tietz, Stefanie AU - Dhingra, Amit AU - Kramer, David M A2 - Niyogi, Krishna K VL - 5 PY - 2016 DA - 2016/10/04 SP - e16921 C1 - eLife 2016;5:e16921 DO - 10.7554/eLife.16921 UR - https://doi.org/10.7554/eLife.16921 AB - The thylakoid proton motive force (pmf) generated during photosynthesis is the essential driving force for ATP production; it is also a central regulator of light capture and electron transfer. We investigated the effects of elevated pmf on photosynthesis in a library of Arabidopsis thaliana mutants with altered rates of thylakoid lumen proton efflux, leading to a range of steady-state pmf extents. We observed the expected pmf-dependent alterations in photosynthetic regulation, but also strong effects on the rate of photosystem II (PSII) photodamage. Detailed analyses indicate this effect is related to an elevated electric field (Δψ) component of the pmf, rather than lumen acidification, which in vivo increased PSII charge recombination rates, producing singlet oxygen and subsequent photodamage. The effects are seen even in wild type plants, especially under fluctuating illumination, suggesting that Δψ-induced photodamage represents a previously unrecognized limiting factor for plant productivity under dynamic environmental conditions seen in the field. KW - photosynthesis KW - proton motive force KW - photoinhibition JF - eLife SN - 2050-084X PB - eLife Sciences Publications, Ltd ER -