ArticleProceedings of the National Academy of Sciences of the United States of America2013
Ammonia binding to the oxygen-evolving complex of photosystem II identifies the solvent-exchangeable oxygen bridge (μ-oxo) of the manganese tetramer.
Article in Proceedings of the National Academy of Sciences of the United States of America, 2013. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 41 papers.
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41 citing papers in PubMed.
- Probing substrate water access through the O1 channel of Photosystem II by single site mutations and membrane inlet mass spectrometry.Photosynthesis research · 2025Article
- Ammonia Binding to the Oxygen-Evolving Complex Probed by High-Energy Resolution Fluorescence Detected X-Ray Absorption Spectroscopy.The journal of physical chemistry. B · 2025Article
- Insights from CaPhotosynthesis research · 2024Review
- The SPhotosynthesis research · 2024Article
- On the simulation and interpretation of substrate-water exchange experiments in photosynthetic water oxidation.Photosynthesis research · 2024Article
- Assignment of the slowly exchanging substrate water of nature's water-splitting cofactor.Proceedings of the National Academy of Sciences of the United States of America · 2024Article
- Comprehensive Evaluation of Models for Ammonia Binding to the Oxygen Evolving Complex of Photosystem II.The journal of physical chemistry. B · 2024Article
- Interplay of two low-barrier hydrogen bonds in long-distance proton-coupled electron transfer for water oxidation.PNAS nexus · 2023Article
- Solar energy conversion by photosystem II: principles and structures.Photosynthesis research · 2023Review
- Does Serial Femtosecond Crystallography Depict State-Specific Catalytic Intermediates of the Oxygen-Evolving Complex?Journal of the American Chemical Society · 2023Article
- Functional Water Networks in Fully Hydrated Photosystem II.Journal of the American Chemical Society · 2022Article
- Magnetic and Electronic Structural Properties of the SACS omega · 2022Article
- Protonation structure of the closed-cubane conformation of the OPNAS nexus · 2022Article
- Reversible Structural Isomerization of Nature's Water Oxidation Catalyst Prior to O-O Bond Formation.Journal of the American Chemical Society · 2022Article
- The exchange of the fast substrate water in the SChemical science · 2021Article
- CaMnAngewandte Chemie (International ed. in English) · 2021Article
- Orientational Jahn-Teller Isomerism in the Dark-Stable State of Nature's Water Oxidase.Angewandte Chemie (International ed. in English) · 2021Article
- Effects of Monochromatic Illumination with LEDs Lights on the Growth and Photosynthetic Performance ofPlants (Basel, Switzerland) · 2021Article
- pKCommunications chemistry · 2020Article
- Water oxidation in photosystem II.Photosynthesis research · 2019Review
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12 authors.
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Abstract
The assignment of the two substrate water sites of the tetra-manganese penta-oxygen calcium (Mn4O5Ca) cluster of photosystem II is essential for the elucidation of the mechanism of biological O-O bond formation and the subsequent design of bio-inspired water-splitting catalysts. We recently demonstrated using pulsed EPR spectroscopy that one of the five oxygen bridges (μ-oxo) exchanges unusually rapidly with bulk water and is thus a likely candidate for one of the substrates. Ammonia, a water analog, was previously shown to bind to the Mn4O5Ca cluster, potentially displacing a water/substrate ligand [Britt RD, et al. (1989) J Am Chem Soc 111(10):3522-3532]. Here we show by a combination of EPR and time-resolved membrane inlet mass spectrometry that the binding of ammonia perturbs the exchangeable μ-oxo bridge without drastically altering the binding/exchange kinetics of the two substrates. In combination with broken-symmetry density functional theory, our results show that (i) the exchangable μ-oxo bridge is O5 {using the labeling of the current crystal structure [Umena Y, et al. (2011) Nature 473(7345):55-60]}; (ii) ammonia displaces a water ligand to the outer manganese (MnA4-W1); and (iii) as W1 is trans to O5, ammonia binding elongates the MnA4-O5 bond, leading to the perturbation of the μ-oxo bridge resonance and to a small change in the water exchange rates. These experimental results support O-O bond formation between O5 and possibly an oxyl radical as proposed by Siegbahn and exclude W1 as the second substrate water.
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