Note to users. If you're seeing this message, it means that your browser cannot find this page's style/presentation instructions -- or possibly that you are using a browser that does not support current Web standards. Find out more about why this message is appearing, and what you can do to make your experience of our site the best it can be.
GoGreen Membership

Site Tools

  • AAAS
  • Subscribe
  • Feedback

Site Search

Search Advanced

Science 3 November 2006:
Vol. 314. no. 5800, pp. 821 - 825
DOI: 10.1126/science.1128186
Prev | Table of Contents | Next

Reports

Where Water Is Oxidized to Dioxygen: Structure of the Photosynthetic Mn4Ca Cluster

Junko Yano,1,2* Jan Kern,3* Kenneth Sauer,1,2 Matthew J. Latimer,4 Yulia Pushkar,1,2 Jacek Biesiadka,5 Bernhard Loll,5{dagger} Wolfram Saenger,5 Johannes Messinger,6{ddagger} Athina Zouni,3{ddagger} Vittal K. Yachandra1{ddagger}

The oxidation of water to dioxygen is catalyzed within photosystem II (PSII) by a Mn4Ca cluster, the structure of which remains elusive. Polarized extended x-ray absorption fine structure (EXAFS) measurements on PSII single crystals constrain the Mn4Ca cluster geometry to a set of three similar high-resolution structures. Combining polarized EXAFS and x-ray diffraction data, the cluster was placed within PSII, taking into account the overall trend of the electron density of the metal site and the putative ligands. The structure of the cluster from the present study is unlike either the 3.0 or 3.5 angstrom–resolution x-ray structures or other previously proposed models.

1 Melvin Calvin Laboratory, Physical Biosciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA.
2 Department of Chemistry, University of California, Berkeley, CA 94720, USA.
3 Max-Volmer-Laboratorium für Biophysikalische Chemie, Technische Universität, Strasse des 17 Juni 135, D-10623 Berlin, Germany.
4 Stanford Synchrotron Radiation Laboratory, 2575 Sand Hill Road, Menlo Park, CA 94305, USA.
5 Institut für Chemie und Biochemie/Kristallographie, Freie Universität, Takustrasse 6, D-14195 Berlin, Germany.
6 Max-Planck-Institut für Bioanorganische Chemie, Stiftstrasse 34–36, D-45470 Mülheim an der Ruhr, Germany.

* These authors contributed equally to this work.

{dagger} Present address: Max-Planck-Institut für Medizinische Forschung, Abteilung für Biomolekulare Mechanismen, Jahnstrasse 29, D-69120 Heidelberg, Germany.

{ddagger} To whom correspondence should be addressed. E-mail: messinger{at}mpi-muelheim.mpg.de (J.M.); zouni{at}phosis1.chem.tu-berlin.de (A.Z.); vkyachandra{at}lbl.gov (V.K.Y.)

Read the Full Text


THIS ARTICLE HAS BEEN CITED BY OTHER ARTICLES:
Biosynthetic Exchange of Bromide for Chloride and Strontium for Calcium in the Photosystem II Oxygen-evolving Enzymes.
N. Ishida, M. Sugiura, F. Rappaport, T.-L. Lai, A. W. Rutherford, and A. Boussac (2008)
J. Biol. Chem. 283, 13330-13340
   Abstract »    Full Text »    PDF »
Enthalpy Changes during Photosynthetic Water Oxidation Tracked by Time-Resolved Calorimetry Using a Photothermal Beam Deflection Technique.
R. Krivanek, H. Dau, and M. Haumann (2008)
Biophys. J. 94, 1890-1903
   Abstract »    Full Text »    PDF »
Structural changes in the Mn4Ca cluster and the mechanism of photosynthetic water splitting.
Y. Pushkar, J. Yano, K. Sauer, A. Boussac, and V. K. Yachandra (2008)
PNAS 105, 1879-1884
   Abstract »    Full Text »    PDF »
Structure and Orientation of the Mn4Ca Cluster in Plant Photosystem II Membranes Studied by Polarized Range-extended X-ray Absorption Spectroscopy.
Y. Pushkar, J. Yano, P. Glatzel, J. Messinger, A. Lewis, K. Sauer, U. Bergmann, and V. Yachandra (2007)
J. Biol. Chem. 282, 7198-7208
   Abstract »    Full Text »    PDF »


ADVERTISEMENT
Click Me!

ADVERTISEMENT
Click Me!

To Advertise     Find Products

Science. ISSN 0036-8075 (print), 1095-9203 (online)