Abstract

The oxygen-evolving complex (OEC) of Photosystem II (PSII) in green plants, algae and cyanobacteria contains a cluster of four manganese atoms as the catalytic site of photo induced oxidation of water to dioxygen. Manganese K-edge x-ray absorption spectroscopy (XAS) studies have done much to help elucidate the structure of this active site, allowing a working model to be proposed. However, to determine the structure of the calcium cofactor binding site, and clarify its possible proximity to the Mn cluster, another approach is required. This proposal seeks to apply extended x-ray absorption fine structure (EXAFS) experiments at the Ca K-edge to target the calcium cofactor present in PSII membranes from spinach and cyanobacteria. The method outlined is element-specific and should be a more direct, sensitive probe of the Ca binding site in as close to a native, unperturbed state as possible. The structure of the functional calcium binding site will also be probed at various intermediate S-states (S0-S3) of the OEC, allowing us to discern the crucial role of calcium in the mechanism of water oxidation.

  Funding Agency

Agency
National Institute of Health (NIH)
Institute
National Center for Research Resources (NCRR)
Type
Biotechnology Resource Grants (P41)
Project #
5P41RR001209-20
Application #
6119621
Study Section
Project Start
1999-03-01
Project End
2000-04-14
Budget Start
1998-10-01
Budget End
1999-09-30
Support Year
20
Fiscal Year
1999
Total Cost
Indirect Cost

  Institution

Name
Stanford University
Department
Type
DUNS #
800771545
City
Stanford
State
CA
Country
United States
Zip Code
94305

  Publications

Lal, Neeraj K; Nagalakshmi, Ugrappa; Hurlburt, Nicholas K et al. (2018) The Receptor-like Cytoplasmic Kinase BIK1 Localizes to the Nucleus and Regulates Defense Hormone Expression during Plant Innate Immunity. Cell Host Microbe 23:485-497.e5
Pluvinage, Benjamin; Grondin, Julie M; Amundsen, Carolyn et al. (2018) Molecular basis of an agarose metabolic pathway acquired by a human intestinal symbiont. Nat Commun 9:1043
Beyerlein, Kenneth R; Jönsson, H Olof; Alonso-Mori, Roberto et al. (2018) Ultrafast nonthermal heating of water initiated by an X-ray Free-Electron Laser. Proc Natl Acad Sci U S A 115:5652-5657
Yoshizawa, Takuya; Ali, Rustam; Jiou, Jenny et al. (2018) Nuclear Import Receptor Inhibits Phase Separation of FUS through Binding to Multiple Sites. Cell 173:693-705.e22
Vickers, Chelsea; Liu, Feng; Abe, Kento et al. (2018) Endo-fucoidan hydrolases from glycoside hydrolase family 107 (GH107) display structural and mechanistic similarities to ?-l-fucosidases from GH29. J Biol Chem 293:18296-18308
Nguyen, Phong T; Lai, Jeffrey Y; Lee, Allen T et al. (2018) Noncanonical role for the binding protein in substrate uptake by the MetNI methionine ATP Binding Cassette (ABC) transporter. Proc Natl Acad Sci U S A 115:E10596-E10604
Aleman, Fernando; Tzarum, Netanel; Kong, Leopold et al. (2018) Immunogenetic and structural analysis of a class of HCV broadly neutralizing antibodies and their precursors. Proc Natl Acad Sci U S A 115:7569-7574
Herrera, Nadia; Maksaev, Grigory; Haswell, Elizabeth S et al. (2018) Elucidating a role for the cytoplasmic domain in the Mycobacterium tuberculosis mechanosensitive channel of large conductance. Sci Rep 8:14566
Dods, Robert; Båth, Petra; Arnlund, David et al. (2017) From Macrocrystals to Microcrystals: A Strategy for Membrane Protein Serial Crystallography. Structure 25:1461-1468.e2
de Vries, Robert P; Tzarum, Netanel; Peng, Wenjie et al. (2017) A single mutation in Taiwanese H6N1 influenza hemagglutinin switches binding to human-type receptors. EMBO Mol Med 9:1314-1325

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