1. The role of metal ions in photosynthesis

2. The green plants produce ~ 1 g glucose every hour per square meter of leaf surface. This means that photosynthesis is the highest volume biochemical process in the Earth, as approximately 200 billion ton carbohydrate equivalent is formed per year in this reaction, although only less than 1% of the radiation reached the Earth is utilised in the photosynthesis. ~10 Nobel prize Solar energy – chemical energy The photosynthesis

3. Photosynthesis

7. Absorption of light and transfer in the photosynthetic system – The photosynthetic reaction centres The electron transport chain between the two photosystems Mn-catalysed oxidation of water to dioxygen (OEC) The role of the ribulose 1,5-diphosphate in the photosystem Evolution – vs. Future outlooks Photosynthesis

8. Absorption of light and transfer in the photosynthetic system – The photosynthetic reaction centres The electrontransport chain between the two photosystems Mn-catalysed oxidation of water to dioxygen (OEC) The role of the ribulose-1,5-diphosphate in the photosystem Evolution – vs. Future outlook Photosynthesis

9. Photosynthesis – utilization of sunlight

11. Pigments of photosynthesis Chlorophyll A

12. Pigments of photosynthesis

13. Structurisation of the pigment materials in the thylakoid membrane in the monomeric antenna complex of the photosystem II (CP43 and CP47 in the antenna complex and D1/D2 in the reaction centre) A and B Figs. show different views. The „antenna” of photosynthesis Science 2004, 303, 1831 Stroma Lumen

14. Structurisation of the pigment materials in the thylakoide membrans in the antenna complexes of photosystem I. A and B Figs. show different views. Current Opinion in Structural Biology 2002, 12, 244 The „antenna” of photosynthesis

15. Transport of the photon energy by resonance transfer

16. The positive characteristics of magnesium ions in the photosynthesis Assure the spatial arrangement of the chlorophyll molecules. The Mg 2+ - ion is perfect for this role: because its size is optimal to form stable complex with the tetrapyrrole ring, furthermore it prefers to form complexes with coordination number six. The Mg 2+ ion forms only weak spin-orbit coupling with the excited state of the tetrapyrrole ring, and thus it hinders the transfer of the energy of light in the forms of fluorescence or heat. The Mg 2+ ion in contrast with most of the transition metal ions can not redox react with the surronding ligands and thus the photosynthetic reaction centres are defended from the unwanted irreversible decomposition.

17. Photosynthesis - photosystems

19. Structurisation of the PS II dimer pigment-protein complex in the thylakoid membrane Science 2004, 303, 1831 Photosyntesis – photosystems II

20. ATP synthesis

21. Absorption of light and transfer in the photosystem – The photosynthetic reaction centres The electron transport chain between the two photosystems Mn catalysed oxidation of water to dioxygen (OEC) The role of ribulose 1,5-diphosphate in the photosystem Evolution – vs. Future outlook Photosynthesis

22. 1.) Iron-sulphur proteins (Ferredoxin): Electrontransfer metalloproteins

23. 2.) Cytochromes: Hem a Hem c Cytochrome c Electrontransfer metalloproteins

24. 3.) Blue copper proteins (Plastocyanin): Electrontransfer metalloproteins

25. The photosynthetic electron transport Z scheme

26. Relative arrangement of the molecules participating in the primary electrontransport processes of PS II system. Science 2004, 303, 1831 Elements of the photosynthetic electrontransport bicarbonate

27. Schematic picture of the b6f complex of the eucaryota photosynthetic electrontransport system. Elements of the photosynthetic electron transport

28. The long range electron transfer and transport systems Schematic picture of a part of the eucariote photosynthetic electrontransport system (cytochrome f → plastocyanin → P700).

29. Reduction of NADP + +H + +2e -

30. Absorption of light and transfer in the photosystem – The photosynthetic reaction centres The electron transport chain between the two photosystems Mn-catalysed oxidation of water to dioxygen (OEC) The role of ribulose 1,5 diphosphate in photosystem Evolution – vs. Future outlook Photosynthesis

31. Oxidation of water

32. +1,2 Oxidation of water

33. Suggested structures of the OEC (WOC) Coordination Chemistry Reviews 2008, 252

34. OEC models from the same X-ray structures Coordination Chemistry Reviews 2008, 252 (A) (B)

35. The amino acids indicated by different colours belong to different protein subunits: yellow - D1, orange - D2 and green - CP43. Schematic figure of the OEC catalytic centre Science 2004, 303, 1831

36. OEC (Oxygen Evolving Complex): The lifetime, the composition of the complex and evolution of protons and electrons in the oxidation steps of water. Schematic figure of oxidation of the water

37. (The question marks indicates that the Mn-Mn distances are not known.) Chemical Reviews 1996, 96, 2947 A proposed mechanism of the stepwise oxidation of water

38. Biochimica et Biophysica Acta 2001, 1503 A proposed mechanism of the stepwise oxidation of water

39. Coordination Chemistry Reviews 2008, 252 A proposed mechanism of the stepwise oxidation of water

40. Proposed structure of OEC (WOC) - 2011 Nature 2011, 473, 55

41. Favourable characteristics of the manganase ions in the photosynthesis (i) Versatility in the stable or metastable oxidation states of manganese: Mn II, Mn III, Mn IV, Mn VI, Mn VII. (ii) Labile coordination of the ligands. (iii) Propensity to form high spin complexes. (iv) The freshly formed mixed valence oxides MnO 2–x ×nH 2 O catalyses efficiently the disproportionation of hydrogene-peroxide, in which oxygen is also formed. Such oxide-hydroxide compounds might also be present, when photosynthesis was evolved. (v) Besides the metabolism of oxygen, the Mn n+ ions occur in other enzymes, such as the Mn containing superoxide dismutases as well as catalases and peroxidases.

42. 1. O 2 channel; 2 and 3. hydrophil channels for the substrate and the proton. Hydrophil and hydrophob channels around the OEC Coordination Chemistry Reviews 2008, 252 (1) (3) (2)

43. Modeling the water flow around the OEC Biochemistry, 2010, 49, 1873

44. Absorption of light and transfer in the photosystem – The photosynthetic reaction centre The electron transport chain between the two photosystems Mn catalysed oxidation of water to dioxygen (OEC) The role of ribulose 1,5-diphosphate in the photosystem Evolution – vs. Future outlook Photosynthesis

45. Reactions of the dark process

46. Schematic picture of the CO2 fixation catalysed by ribulose 1,5 diphosphate carboxylase enzyme. Reactions of the dark process

47. Schematic picture of the CO2 fixation catalysed by ribulose 1,5 diphosphate carboxylase enzyme. Reactions of the dark process

48. X-ray structure of the ribulose 1,5-diphosphate carboxylase enzyme C. Reinhardtii green algae. The L subunits are indicated by blue and green, while the S subunits by yellow colour. Structure of the ribulose 1,5 diphosphate carboxylase Journal of Molecular Biology 2002, 316, 679

49. Active centre of the ribulose 1,5-diphosphate carboxylase enzyme of C. Reinhardtii green algae in the presence of a model substrate. Active centre of the ribulose 1,5-diphosphate carboxylase Journal of Molecular Biology 2002, 316, 679

50. Absorption of light and transfer in the photosystem – The photosynthetic reaction centre The electron transport chain between the two photosystems Mn catalysed oxidation of water to dioxygen (OEC) The role of ribulose 1,5-diphosphate in the photosystem Evolution – vs. Future outlook Photosynthesis

51. Evolution of photosynthesis Reaction centre of the purple bacteria Green sulphur bacteria:

52. The photosynthesis

53. Artificial photosynthesis

54. Coordination Chemistry Reviews 252 (2008) 444 Artificial photosynthesis

55. Coordination Chemistry Reviews 252 (2008) 456 Artificial photosynthesis

56. Photosynthetic car?