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Biochemical Characterization of the Plastid Terminal Oxidase and Its Implication in Photosynthesis

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Biochemical Characterization of the Plastid Terminal Oxidase and Its Implication in Photosynthesis NNT : 2015SACLS051 THESE DE DOCTORAT DE L’UNIVERSITE PARIS-SACLAY PREPAREE A I2BC, CEA Saclay, Institut de Biologie et de Technologie de Saclay, Centre National de la Recherche Scientifique, 91191 Gif-sur-Yvette, France ÉCOLE DOCTORALE N°567 Sciences du végétal : du gène à l'écosystème Spécialité Biologie Par Mme Kathleen FEILKE Biochemical characterization of the plastid terminal oxidase and its implication in photosynthesis Thèse présentée et soutenue à Gif-sur-Yvette, le 23 octobre 2015 devant le jury composé de: M. Fabrice RAPPAPORT Directeur de Recherche Rapporteur CNRS (IBPC Paris) M. Peter NIXON Professeur Rapporteur Imperial College (Londres) M. Graham NOCTOR Professeur Président Université Paris-Sud (Orsay) M. Marcel KUNTZ Directeur de Recherche Examinateur CNRS (CEA Grenoble) Mme. Anja KRIEGER-LISZKAY Directeur de Recherche Directeur de thèse CNRS (CEA Saclay) ACKNOWLEDGEMENTS ............................................................................................ 5 ABBREVIATIONS ......................................................................................................... 7 1 INTRODUCTION AND AIMS .............................................................................. 9 1.1 Chloroplast and photosynthesis ............................................................................. 11 Organisation of the thylakoid membrane structure ................................................. 11 The primary processes of photosynthesis ................................................................ 12 Light harvesting antenna ..................................................................................... 13 Photosystem II ..................................................................................................... 14 Plastoquinone ...................................................................................................... 15 Cytochrome b6f complex ..................................................................................... 15 Plastocyanin ......................................................................................................... 16 Photosystem I ...................................................................................................... 16 ATP synthase ....................................................................................................... 17 The secondary processes of photosynthesis ............................................................ 17 The Calvin-Benson-Bassham cycle ..................................................................... 17 Photorespiration ................................................................................................... 18 Malate valve ............................................................................................................ 19 Alternative electron routes in photosynthesis ......................................................... 20 Cyclic electron flow around PSI ......................................................................... 20 Mehler reaction .................................................................................................... 22 Chlororespiration ................................................................................................. 22 Regulation of photosynthetic electron transport ..................................................... 23 Reactive oxygen species and antioxidant defenses ............................................. 24 Photosynthetic control at the cytochrome b6f complex ....................................... 26 Non-photochemical quenching of chlorophyll a fluorescenece .......................... 26 Acclimatisation of photosynthesis to environmental changes ............................ 28 1.2 Non-heme diiron proteins ...................................................................................... 30 Methane monooxygenase ........................................................................................ 31 2 Ribonucleotide reductase ........................................................................................ 33 Alternative oxidase .................................................................................................. 33 Plastid terminal oxidase ........................................................................................... 34 PTOX and carotenoid biosynthesis ..................................................................... 35 PTOX and chlororespiration ............................................................................... 36 PTOX and abiotic stress ...................................................................................... 37 1.3 Aims ...................................................................................................................... 38 2 In vitro characterization of PTOX ....................................................................... 39 2.1 Functional and molecular characterization of plastid terminal oxidase from rice.40 Introduction ............................................................................................................. 41 Paper 1 ................................................................................................................... 42 PTOX oligomerization and its catalytically active state ......................................... 77 2.2 In vitro characterization of recombinant PTOX in photosynthetic electron transport ...................................................................................................................... 78 Introduction ............................................................................................................. 79 Effect of Zn2+ on PTOX activity............................................................................ 113 3 In vivo characterization of PTOX ...................................................................... 114 3.1 Effect of constitutive expression of bacterial phytoene desaturase CRTI on photosynthetic electron transport in Arabidopsis thaliana ........................................ 116 Introduction ........................................................................................................... 116 Paper 3 ................................................................................................................. 117 Crossing immutans with CRTI: Effect of PTOX mutation on photosynthetic electron transport without impact on phytoene desaturation ................................. 156 3.2 Chlamydomonas plastid terminal oxidase expressed in tobacco competes with photosynthetic electron transport and its activity is regulated by the proton-gradient across the thylakoid membrane ................................................................................. 158 Introduction ........................................................................................................... 158 3 Paper 4 ................................................................................................................. 159 4. The dual role of the plastid terminal oxidase PTOX: between a protective and a pro-oxidant function (Paper 5) ................................................................................ 207 5. Expression of PTOX in Synechocystis ............................................................... 203 Abstract ..................................................................................................................... 204 Introduction ............................................................................................................... 204 Material and Methods ................................................................................................ 205 Results and discussion ............................................................................................... 208 6. DISCUSSION ....................................................................................................... 213 7. CONCLUSION .................................................................................................... 225 8. SUMMARY .......................................................................................................... 229 9. RESUMEE ........................................................................................................... 233 10. ZUSAMMENFASSUNG ..................................................................................... 237 11. REFERENCES .................................................................................................... 241 4 ACKNOWLEDGEMENTS Though only my name appears on the cover of this manuscript, a great number of people have contributed to its production. I owe my gratitude to all those people who have made this possible. Thanks for everybody who helped me get to this day. I am very grateful to my supervisor Anja Krieger-Liszkay for the excellent guidance, her encouragement, her patience and help during the past few years. I have been amazingly fortunate to have a supervisor who gave me the freedom to explore on my own and at the same time the guidance to recover when I failed. Then I would like to thank Peter Nixon for providing me with seeds overexpressing PTOX and for accepting to review my manuscript. At the same time I would like to thank Fabrice Rappaport for reviewing my manuscript and for useful discussion time. Moreover, I would like to thank Marcel Kuntz for his time to discuss about PTOX and supply with very useful PTOX antibody. I would also like to thank him and Graham Noctor for accepting to examine
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