Photosynthesis Research

, Volume 97, Issue 1, pp 91–114 | Cite as

Computational insights into the O2-evolving complex of photosystem II

  • Eduardo M. Sproviero
  • James P. McEvoy
  • José A. Gascón
  • Gary W. Brudvig
  • Victor S. Batista


Mechanistic investigations of the water-splitting reaction of the oxygen-evolving complex (OEC) of photosystem II (PSII) are fundamentally informed by structural studies. Many physical techniques have provided important insights into the OEC structure and function, including X-ray diffraction (XRD) and extended X-ray absorption fine structure (EXAFS) spectroscopy as well as mass spectrometry (MS), electron paramagnetic resonance (EPR) spectroscopy, and Fourier transform infrared spectroscopy applied in conjunction with mutagenesis studies. However, experimental studies have yet to yield consensus as to the exact configuration of the catalytic metal cluster and its ligation scheme. Computational modeling studies, including density functional (DFT) theory combined with quantum mechanics/molecular mechanics (QM/MM) hybrid methods for explicitly including the influence of the surrounding protein, have proposed chemically satisfactory models of the fully ligated OEC within PSII that are maximally consistent with experimental results. The inorganic core of these models is similar to the crystallographic model upon which they were based, but comprises important modifications due to structural refinement, hydration, and proteinaceous ligation which improve agreement with a wide range of experimental data. The computational models are useful for rationalizing spectroscopic and crystallographic results and for building a complete structure-based mechanism of water-splitting in PSII as described by the intermediate oxidation states of the OEC. This review summarizes these recent advances in QM/MM modeling of PSII within the context of recent experimental studies.


Oxomanganese complexes Photosystem II Water oxidation Oxygen evolution Oxygen evolving center Photosynthesis Quantum mechanics/molecular mechanics (QM/MM) Density functional theory (DFT) 



V.S.B. acknowledges supercomputer time from the National Energy Research Scientific Computing (NERSC) center and financial support from Research Corporation, Research Innovation Award # RI0702, a Petroleum Research Fund Award from the American Chemical Society PRF # 37789-G6, a junior faculty award from the F. Warren Hellman Family, the National Science Foundation (NSF) Career Program Award CHE # 0345984, the NSF Award ECCS # 0725118, the Alfred P. Sloan Fellowship (2005–2006), a Camille Dreyfus Teacher-Scholar Award for 2005–2006, the National Institutes of Health (NIH) grant 2R01-GM043278-14 and a Yale Junior Faculty Fellowship in the Natural Sciences (2005–2006). G.W.B acknowledges support from the NIH grant GM32715. J.A.G acknowledges support from the Pittsburgh Supercomputer Center, teragrid project TG-CHEM060028T, and the Camille & Henry Dreyfus New Faculty Award for 2006.


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Copyright information

© Springer Science+Business Media B.V. 2008

Authors and Affiliations

  • Eduardo M. Sproviero
    • 1
  • James P. McEvoy
    • 1
    • 2
  • José A. Gascón
    • 1
    • 3
  • Gary W. Brudvig
    • 1
  • Victor S. Batista
    • 1
  1. 1.Department of ChemistryYale UniversityNew HavenUSA
  2. 2.Department of ChemistryRegis UniversityDenverUSA
  3. 3.Department of ChemistryUniversity of ConnecticutStorrsUSA

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