Photosystem II: The Reaction Center of Oxygenic Photosynthesis

Vinyard, David J.; Ananyev, Gennady; Dismukes, G. Charles

doi:10.1146/annurev-biochem-070511-100425

Cited by 335 publications

(301 citation statements)

References 203 publications

Supporting

Mentioning

294

Contrasting

Unclassified

Order By: Relevance

“…The mechanism, established earlier for single-site molecular catalysts (12,13), is shown in Scheme 2 and reenters the catalytic cycle. In Scheme 1, "RDS" denotes the rate-determining step.…”

mentioning

confidence: 55%

“…It uses a derivatized, core-shell nanostructured photoanode with the core a high surface area conductive metal oxide film--indium tin oxide or antimony tin oxide--coated with a thin outer shell of TiO 2 formed by atomic layer deposition. A "chromophore-catalyst assembly" 1, [(PO 3 H 2 ) 2 bpy) 2 Ru(4-Mebpy-4-bimpy)Rub(tpy)(OH 2 )] 4+ , which combines both light absorber and water oxidation catalyst in a single molecule, was attached to the TiO 2 shell. Visible photolysis of the resulting core-shell assembly structure with a Pt cathode resulted in water splitting into hydrogen and oxygen with an absorbed photon conversion efficiency of 4.4% at peak photocurrent.…”

mentioning

confidence: 99%

“…At photosystem II, a subsystem imbedded in the thylakoid membrane where O 2 is produced, light absorption, energy migration, electron transfer, proton transfer, and catalysis are all used in multiple stepwise chemical reactions which are carefully orchestrated at the molecular level (1,2).…”

mentioning

confidence: 99%

“…1. It illustrates the interface and the structure of chromophorecatalyst assembly 1, [(PO 3 H 2 ) 2 bpy) 2 Ru a (4-Mebpy-4′-bimpy)Ru b (tpy) (OH 2 )] 4+ ((PO 3 H 2 ) 2 bpy is 4,4′-bisphosphonato-2,2′-bipyridine; 4-Mebpy-4′-bimpy is 4-(methylbipyridin-4′-yl)-N-benzimid-N′-pyridine; tpy is 2,2′:6′,2″-terpyridine)). It also illustrates the dynamic events that occur at the derivatized interface following light absorption by the surface-bound chromophore.…”

mentioning

confidence: 99%

See 3 more Smart Citations

Solar water splitting in a molecular photoelectrochemical cell

Alibabaei

Brennaman

Norris

et al. 2013

Proc. Natl. Acad. Sci. U.S.A.

210

231

View full text Add to dashboard Cite

Artificial photosynthesis and the production of solar fuels could be a key element in a future renewable energy economy providing a solution to the energy storage problem in solar energy conversion. We describe a hybrid strategy for solar water splitting based on a dye sensitized photoelectrosynthesis cell. It uses a derivatized, core-shell nanostructured photoanode with the core a high surface area conductive metal oxide film--indium tin oxide or antimony tin oxide--coated with a thin outer shell of TiO 2 formed by atomic layer deposition. A "chromophore-catalyst assembly" 1, [(PO 3 H 2 ) 2 bpy) 2 Ru(4-Mebpy-4-bimpy)Rub(tpy)(OH 2 )] 4+ , which combines both light absorber and water oxidation catalyst in a single molecule, was attached to the TiO 2 shell. Visible photolysis of the resulting core-shell assembly structure with a Pt cathode resulted in water splitting into hydrogen and oxygen with an absorbed photon conversion efficiency of 4.4% at peak photocurrent.P hotosynthesis uses the energy of the sun with water as the reducing agent to drive the reduction of carbon dioxide to carbohydrates with oxygen as a coproduct through a remarkably complex process. At photosystem II, a subsystem imbedded in the thylakoid membrane where O 2 is produced, light absorption, energy migration, electron transfer, proton transfer, and catalysis are all used in multiple stepwise chemical reactions which are carefully orchestrated at the molecular level (1, 2).Photosynthesis solves the problem of energy storage by biomass production but with low solar efficiencies, typically <1%. In artificial photosynthesis with solar fuels production, the goal is similar but the targets are either hydrogen production from water splitting, Eq. 1, or reduction of carbon dioxide to a carbon-based fuel, Eq. 2 (3, 4). Different strategies for solar fuels have evolved (5, 6). In one, direct bandgap excitation of semiconductors creates electron-hole pairs which are then used to drive separate halfreactions for water oxidation (2H 2 O → O 2 + 4H + + 4e − ) and water/proton reduction (2H + + 2e − → H 2 ) (7-9).Here, we report a hybrid strategy for solar water splitting, the dye sensitized photoelectrosynthesis cell (DSPEC). It combines the electron transport properties of semiconductor nanocrystalline thin films with molecular-level reactions (10). In this approach, a chromophore-catalyst molecular assembly acts as both light absorber and catalyst. It is bound to the surface of a "core-shell," nanostructured, transparent conducting oxide film. The core structure consists of a nanoparticle film of either tin-doped indium oxide (nanoITO), or antimony-doped tin oxide (nanoATO), deposited on a fluoride-doped tin oxide (FTO) glass substrate. The shell consists of a conformal TiO 2 nanolayer applied by atomic layer deposition (ALD). The resulting "photoanode," where water oxidation occurs, is connected to a Pt cathode for proton reduction to complete the water splitting cell. A diagram for the photoanode in the DSPEC device is shown in Fig. 1. It illustrates...

show abstract

mentioning

confidence: 55%

mentioning

confidence: 99%

mentioning

confidence: 99%

mentioning

confidence: 99%

See 2 more Smart Citations

Solar water splitting in a molecular photoelectrochemical cell

Alibabaei

Brennaman

Norris

et al. 2013

Proc. Natl. Acad. Sci. U.S.A.

210

231

View full text Add to dashboard Cite

show abstract

“…P hotosystem II (PSII) functions as a water-plastoquinone oxidoreductase (1,2) and is a thylakoid membrane pigmentprotein complex present in all oxygenic photosynthetic organisms (cyanobacteria, algae, and higher plants). Current high-resolution structures of thermophilic cyanobacterial PSII (3,4), and lower resolution structures of the red algal (5) and higher plant photosystems (6), have been critically important in furthering our understanding of the molecular organization of PSII.…”

mentioning

confidence: 99%

Amino acid oxidation of the D1 and D2 proteins by oxygen radicals during photoinhibition of Photosystem II

Kale

Hebert

Frankel

et al. 2017

Proc. Natl. Acad. Sci. U.S.A.

121

View full text Add to dashboard Cite

The Photosystem II reaction center is vulnerable to photoinhibition. The D1 and D2 proteins, lying at the core of the photosystem, are susceptible to oxidative modification by reactive oxygen species that are formed by the photosystem during illumination. Using spin probes and EPR spectroscopy, we have determined that both O 2 . The identification of specific amino acid residues oxidized by reactive oxygen species provides insights into the mechanism of damage to the D1 and D2 proteins under light stress.photosynthesis | Photosystem II | reactive oxygen species | photo inhibition | mass spectrometry P hotosystem II (PSII) functions as a water-plastoquinone oxidoreductase (1, 2) and is a thylakoid membrane pigmentprotein complex present in all oxygenic photosynthetic organisms (cyanobacteria, algae, and higher plants). Current high-resolution structures of thermophilic cyanobacterial PSII (3, 4), and lower resolution structures of the red algal (5) and higher plant photosystems (6), have been critically important in furthering our understanding of the molecular organization of PSII. Structurally, the PSII reaction center core is composed of five proteins: D1, D2, the α-and β-subunits of cytochrome b 559 , and PsbI. These components bind all of the redox-active cofactors of PSII.Excitation energy transfer and electron transport within PSII are unavoidably associated with production of reactive oxygen species (ROS) when the absorption of light by the chlorophyll antenna exceeds the capacity for energy utilization. Many mechanisms for ROS production have been proposed (for reviews, see refs. 7 and 8). Briefly, singlet oxygen ( 1 O 2 ) may be formed by excitation energy transfer from triplet chlorophylls (formed either by the change in orientation of the spin of an excited electron in the PSII antenna complex, or via charge recombination of the primary radical pair 3 [P 680 •+ Pheo •− ]) to O 2 (9, 10). ROS production by electron transport involves either the two-electron oxidation of water or the one-electron reduction of O 2 on the PSII electron donor and acceptor sides, respectively. On the PSII electron donor side, a twoelectron oxidation of water leads to the formation of hydrogen peroxide (H 2 O 2 ), which may be oxidized to the superoxide anion radical (O 2•−

show abstract

Environmental pH and a Glu364 to Gln mutation in the chlorophyll‐binding CP47 protein affect redox‐active TyrD and charge recombination in Photosystem II

et al. 2018

View full text Add to dashboard Cite

In Photosystem II, loop E of the chlorophyll‐binding CP47 protein is located near a redox‐active tyrosine, YD, forming a symmetrical analog to loop E in CP43, which provides a ligand to the oxygen‐evolving complex (OEC). A Glu364 to Gln substitution in CP47, near YD, does not affect growth in the cyanobacterium Synechocystis sp. PCC 6803; however, deletion of the extrinsic protein PsbV in this mutant leads to a strain displaying a pH‐sensitive phenotype. Using thermoluminescence, chlorophyll fluorescence, and flash‐induced oxygen evolution analyses, we demonstrate that Glu364 influences the stability of YD and the redox state of the OEC, and highlight the effects of external pH on photosynthetic electron transfer in intact cyanobacterial cells.

show abstract

Photosystem II: The Reaction Center of Oxygenic Photosynthesis

Cited by 335 publications

References 203 publications

Solar water splitting in a molecular photoelectrochemical cell

Solar water splitting in a molecular photoelectrochemical cell

Amino acid oxidation of the D1 and D2 proteins by oxygen radicals during photoinhibition of Photosystem II

Environmental pH and a Glu364 to Gln mutation in the chlorophyll‐binding CP47 protein affect redox‐active TyrD and charge recombination in Photosystem II

Contact Info

Product

Resources

About