The mechanism for proton-coupled electron transfer from tyrosine in a model complex and comparisons with Y(Z) oxidation in photosystem II
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Updated: Sep 28, 2026

A New Approach for the Comparative Analysis of Multiprotein Complexes Based on 15N Metabolic Labeling and Quantitative Mass Spectrometry
Published on: March 13, 2014
Martin Sjödin1, Stenbjörn Styring, Björn Akermark
1Department of Physical Chemistry, Uppsala University, Box 532, S-751 21 Uppsala, Sweden.
Abstract:
In the water-oxidizing reactions of photosystem II (PSII), a tyrosine residue plays a key part as an intermediate electron-transfer reactant between the primary donor chlorophylls (the pigment P(680)) and the water-oxidizing Mn cluster. The tyrosine is deprotonated upon oxidation, and the coupling between the proton reaction and electron transfer is of great mechanistic importance for the understanding of the water-oxidation mechanism. Within a programme on artificial photosynthesis, we have made and studied the proton-coupled tyrosine oxidation in a model system and been able to draw mechanistic conclusions that we use to interpret the analogous reactions in PSII.
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