The Dual Role of the Plastid Terminal Oxidase PTOX: Between a Protective and a Pro-oxidant Function

Krieger‐Liszkay, Anja; Feilke, Kathleen

doi:10.3389/fpls.2015.01147

Cited by 61 publications

(55 citation statements)

References 23 publications

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“…In chlororespiration NAD(P)H produced in the stroma of chloroplasts reduces plastoquinone, a reaction catalyzed by NADH‐dehydrogenase (NDH) (Peltier and Cournac ). Plastoquinol is the substrate of the plastid terminal oxidase (PTOX) which reduces O 2 to H 2 O (Krieger‐Liszkay and Feilke ). We tested the effects of NDH on the post‐illumination transient O 2 ‐uptake in rice plants, which is deficient in NDH activity (Fig.…”

Section: Discussionmentioning

confidence: 99%

Land plants drive photorespiration as higher electron‐sink: comparative study of post‐illumination transient O₂‐uptake rates from liverworts to angiosperms through ferns and gymnosperms

Hanawa

Ishizaki

Nohira

et al. 2017

Physiologia Plantarum

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In higher plants, the electron-sink capacity of photorespiration contributes to alleviation of photoinhibition by dissipating excess energy under conditions when photosynthesis is limited. We addressed the question at which point in the evolution of photosynthetic organisms photorespiration began to function as electron sink and replaced the flavodiiron proteins which catalyze the reduction of O at photosystem I in cyanobacteria. Algae do not have a higher activity of photorespiration when CO assimilation is limited, and it can therefore not act as an electron sink. Using land plants (liverworts, ferns, gymnosperms, and angiosperms) we compared photorespiration activity and estimated the electron flux driven by photorespiration to evaluate its electron-sink capacity at CO -compensation point. In vivo photorespiration activity was estimated by the simultaneous measurement of O -exchange rate and chlorophyll fluorescence yield. All C3-plants leaves showed transient O -uptake after actinic light illumination (post-illumination transient O -uptake), which reflects photorespiration activity. Post-illumination transient O -uptake rates increased in the order from liverworts to angiosperms through ferns and gymnosperms. Furthermore, photorespiration-dependent electron flux in photosynthetic linear electron flow was estimated from post-illumination transient O -uptake rate and compared with the electron flux in photosynthetic linear electron flow in order to evaluate the electron-sink capacity of photorespiration. The electron-sink capacity at the CO -compensation point also increased in the above order. In gymnosperms photorespiration was determined to be the main electron-sink. C3-C4 intermediate species of Flaveria plants showed photorespiration activity, which intermediate between that of C3- and C4-flaveria species. These results indicate that in the first land plants, liverworts, photorespiration started to function as electron sink. According to our hypothesis, the dramatic increase in partial pressure of O in the atmosphere about 0.4 billion years ago made it possible to drive photorespiration with higher activity in liverworts.

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Section: Discussionmentioning

confidence: 99%

Land plants drive photorespiration as higher electron‐sink: comparative study of post‐illumination transient O₂‐uptake rates from liverworts to angiosperms through ferns and gymnosperms

Hanawa

Ishizaki

Nohira

et al. 2017

Physiologia Plantarum

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“…It has been suggested that PTOX provides an alternative electron flow from the PQ pool to O 2 to prevent photoinhibition of PSII [311]. However, in higher plants, PTOX-mediated electron flow to O 2 is negligible [312] or its contribution is less than one percent of the total electron flow through PETC [313,314]. However, PTOX may depend on conditions, as high PTOX content and high PTOX activity were induced in the alpine species Ranunculus glacialis L. during growth in strong light [315].…”

Section: Formation Of Reduced Forms Of Oxygenmentioning

confidence: 99%

Oxygen and ROS in Photosynthesis

Khorobrykh

Havurinne

Mattila

et al. 2020

Plants

170

133

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Oxygen is a natural acceptor of electrons in the respiratory pathway of aerobic organisms and in many other biochemical reactions. Aerobic metabolism is always associated with the formation of reactive oxygen species (ROS). ROS may damage biomolecules but are also involved in regulatory functions of photosynthetic organisms. This review presents the main properties of ROS, the formation of ROS in the photosynthetic electron transport chain and in the stroma of chloroplasts, and ROS scavenging systems of thylakoid membrane and stroma. Effects of ROS on the photosynthetic apparatus and their roles in redox signaling are discussed.

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“…The low rate of electron flow sustained by PTOX ranges from 0.1 to 5 e 2 PSII 21 s 21 in the chloroplasts of plants and C. reinhardtii (Houille-Vernes et al, 2011;Trouillard et al, 2012), which does not qualify PTOX as an efficient electron sink. Despite its low reaction rate, PTOX has been suggested to play a photoprotective role when the light absorption by PSII exceeds the capacity of the downstream reactions (Carol et al, 1999;Niyogi, 2000;Ort and Baker, 2002;Krieger-Liszkay and Feilke, 2016;Stepien and Johnson, 2018). We first examined the participation of PTOX in a pathway that reroutes electrons from PSII by monitoring the electron transfer rate (ETR PSII ) in the wild type and the ptox2 mutant over a wide range of light intensities.…”

Section: Ptox2 Cannot Compete With Cyt B 6 F-psi For Oxidation Of Thmentioning

confidence: 99%

Chlororespiration Controls Growth Under Intermittent Light

et al. 2018

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The Dual Role of the Plastid Terminal Oxidase PTOX: Between a Protective and a Pro-oxidant Function

Cited by 61 publications

References 23 publications

Land plants drive photorespiration as higher electron‐sink: comparative study of post‐illumination transient O₂‐uptake rates from liverworts to angiosperms through ferns and gymnosperms

Land plants drive photorespiration as higher electron‐sink: comparative study of post‐illumination transient O₂‐uptake rates from liverworts to angiosperms through ferns and gymnosperms

Oxygen and ROS in Photosynthesis

Chlororespiration Controls Growth Under Intermittent Light

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The Dual Role of the Plastid Terminal Oxidase PTOX: Between a Protective and a Pro-oxidant Function

Cited by 61 publications

References 23 publications

Land plants drive photorespiration as higher electron‐sink: comparative study of post‐illumination transient O2‐uptake rates from liverworts to angiosperms through ferns and gymnosperms

Land plants drive photorespiration as higher electron‐sink: comparative study of post‐illumination transient O2‐uptake rates from liverworts to angiosperms through ferns and gymnosperms

Oxygen and ROS in Photosynthesis

Chlororespiration Controls Growth Under Intermittent Light

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Product

Resources

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Land plants drive photorespiration as higher electron‐sink: comparative study of post‐illumination transient O₂‐uptake rates from liverworts to angiosperms through ferns and gymnosperms

Land plants drive photorespiration as higher electron‐sink: comparative study of post‐illumination transient O₂‐uptake rates from liverworts to angiosperms through ferns and gymnosperms