1. S-state cycle of water oxidation by the manganese cluster (shown as circles with roman numerals representing the manganese ion oxidation states) within the PSII oxygen-evolving complex
S-state cycle of water oxidation by the manganese cluster (shown as circles with roman numerals representing the manganese ion oxidation states) within the PSII oxygen-evolving complex Progressive extraction of electrons from the manganese cluster is driven by the oxidation of P680 within PSII by light. Each of the electrons given up by the cluster is eventually repaid at the S4 to S0 transition when molecular oxygen (O2) is formed. The protons extracted from water during the process are deposited into the lumen and contribute to the protonmotive force.
Matthew P. Johnson Essays Biochem. 2016;60:
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