Oxygen, Water, Proton and Quinone Channels in PSII

  • James Murray
  • James Barber

Abstract

Using the crystal structure of Photosystem II (PSII) we have investigated the presence of channels for the entry of substrates, and exits of products, from catalytic sites within the complex. We identify three channels from the oxygen evolving centre, which we associate with possible water entry and the exit of proton and dioxygen. At the acceptor side, we examine the cavity adjacent to the QB site, and discuss its possible role as channel for plastoquinone/plastoquinol diffusion in and out of PSII.

Keywords

photosystem II crystal structure substrate channels oxygen pathways structural bioinformatics 

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Copyright information

© Springer Science + Business Media, B.V. 2008

Authors and Affiliations

  • James Murray
    • 1
  • James Barber
    • 1
  1. 1.Wolfson Laboratories, Division of Molecular Biosciences, Faculty of Natural SciencesImperial College LondonLondonUK

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