Crystal structure of oxygen-evolving photosystem II at a resolution of 1.9 Å

  title={Crystal structure of oxygen-evolving photosystem II at a resolution of 1.9 {\AA}},
  author={Yasufumi Umena and Keisuke Kawakami and Jian-Ren Shen and Nobuo Kamiya},
Photosystem II is the site of photosynthetic water oxidation and contains 20 subunits with a total molecular mass of 350 kDa. The structure of photosystem II has been reported at resolutions from 3.8 to 2.9 Å. These resolutions have provided much information on the arrangement of protein subunits and cofactors but are insufficient to reveal the detailed structure of the catalytic centre of water splitting. Here we report the crystal structure of photosystem II at a resolution of 1.9 Å. From our… 

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An apparent elongation in the bond distance between Sr and one of the two terminal water ligands of Ca2+, W3, whereas that of the Sr-W4 distance was not much changed may contribute to the decrease of oxygen evolution upon Sr2+-substitution, and suggests a weak binding and rather mobile nature of this particular water molecule (W3).

The Structure of Photosystem II and the Mechanism of Water Oxidation in Photosynthesis.

The overall structure of PSII is provided followed by detailed descriptions of the specific structure of the Mn4CaO5 cluster and its surrounding protein environment, based on the geometric organization revealed by the crystallographic analysis.

Oxygen‐evolving Photosystem II

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Photosystem II: the water-splitting enzyme of photosynthesis.

  • J. Barber
  • Chemistry
    Cold Spring Harbor symposia on quantitative biology
  • 2012
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Heterogeneous Composition of Oxygen-Evolving Complexes in Crystal Structures of Dark-Adapted Photosystem II.

It is found that the two OECs of dark-adapted PSII dimers in crystals are not fully synchronized in the S1 state, indicating heterogeneity in the OEC composition.

Structure of photosystem II and substrate binding at room temperature

Ammonia, a water analogue, has been used as a marker, as it binds to the Mn4CaO5 cluster in the S2 and S3 states, and this approach, together with a comparison of the native dark and 2F states, is used to discriminate between proposed O–O bond formation mechanisms.

Electronic structure of the oxygen-evolving complex in photosystem II prior to O-O bond formation

Frequency, multidimensional magnetic resonance spectroscopy reveals that all four manganese ions of the catalyst are structurally and electronically similar immediately before the final oxygen evolution step; they all exhibit a 4+ formal oxidation state and octahedral local geometry.

Rationalizing the 1.9 Å crystal structure of photosystem II--A remarkable Jahn-Teller balancing act induced by a single proton transfer.

XRD structures of PS II at progressively improved resolution reveal the positions of bridging O atoms within the Mn4Ca core of the WOC for the first time, and an atomic resolution structure at 1.9 is produced, the most resolved to date.

Water oxidation in photosystem II

How magnetic resonance techniques, particularly EPR, complemented by quantum chemical calculations, have played an important role in understanding the electronic structure of the cofactor is described and shown that these data are instrumental for developing a model of the biological water oxidation cycle.



Crystal structure of photosystem II from Synechococcus elongatus at 3.8 Å resolution

The X-ray structure of photosystem II is described on the basis of crystals fully active in water oxidation, shows how protein subunits and cofactors are spatially organized and the larger subunits are assigned and the locations and orientations of the cofacters are defined.

Architecture of the Photosynthetic Oxygen-Evolving Center

The data strongly suggest that the OEC contains a cubane-like Mn3CaO4 cluster linked to a fourth Mn by a mono-μ-oxo bridge, and the details of the surrounding coordination sphere of the metal cluster and the implications for a possible oxygen-evolving mechanism are discussed.

An evaluation of structural models for the photosynthetic water-oxidizing complex derived from spectroscopic and X-ray diffraction signatures

A unified interpretation of debated structural proposals and Mn oxidation states is provided, based on an integrated analysis of the published data, particularly from Mn X-ray absorption spectroscopy (XAS) and EPR/ENDOR data.

Crystal Structure of Monomeric Photosystem II from Thermosynechococcus elongatus at 3.6-Å Resolution*

The first crystallization and structural analysis of the monomeric form of PSIIcc with high oxygen evolution capacity, isolated from Thermosynechococcus elongatus is reported, and the roles of lipids and protein subunits in dimer formation of PS IIcc are discussed.

Protein Ligation of the Photosynthetic Oxygen-Evolving Center.

  • R. Debus
  • Chemistry
    Coordination chemistry reviews
  • 2008

Cyanobacterial photosystem II at 2.9-Å resolution and the role of quinones, lipids, channels and chloride

Putative oxygen positions obtained from a Xenon derivative indicate a role for lipids in oxygen diffusion to the cytoplasmic side of PSII, and the chloride position suggests a role in proton-transfer reactions.

Crystallization and the crystal properties of the oxygen-evolving photosystem II from Synechococcus vulcanus.

A photosystem II (PSII) complex highly active in oxygen evolution was purified and crystallized from a thermophilic cyanobacterium, Synechococcus vulcanus, indicating that the PSII crystallized is a dimer.

X-ray crystallography identifies two chloride binding sites in the oxygen evolving centre of Photosystem II

Bromide anomalous X-ray diffraction analyses have been used to locate chloride binding sites in the vicinity of the water splitting/oxygen evolving centre (OEC) of Photosystem II. Three-dimensional

Excited-state dynamics in photosystem II: Insights from the x-ray crystal structure

A kinetic model for PSII, based on the x-ray crystal structure coordinates of 37 antenna and reaction center pigment molecules, allows us to map the major energy transfer routes from the antenna chlorophylls to the reaction center chromophores and predicts a value for the intrinsic photochemical rate constant that is 4 times that found in bacterial reaction centers.

Location of chloride and its possible functions in oxygen-evolving photosystem II revealed by X-ray crystallography

Results indicate that these 2 Cl− anions are required to maintain the coordination structure of the Mn4Ca cluster as well as the proposed proton channel, thereby keeping the oxygen-evolving complex fully active.