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Updated: Feb 12, 2026

Rapid Scan Electron Paramagnetic Resonance Opens New Avenues for Imaging Physiologically Important Parameters In Vivo
Published on: September 26, 2016
Magnetic structure of manganese cluster in photosystem II investigated by electron paramagnetic resonance
Hiroki Nagashima1, Mizue Asada1, Hiroyuki Mino1
1Division of Material Science (Physics), Graduate School of Science, Nagoya University, Nagoya, Aichi 464-8602, Japan.
Abstract:
The electronic structure of manganese (Mn) cluster in photosystem II was investigated by electron paramagnetic resonance (EPR) spectroscopy. In order to determine the spin density distribution in magnetically coupled Mn in the S2 state Mn cluster, pulsed electron-electron double resonance (PELDOR) measurement was performed. The local environment of the Mn cluster was investigated by electron-nuclear double resonance (ENDOR). Using spin projections determined by PELDOR, ENDOR signals were assigned to the water molecules ligated to the Mn cluster. The location of a high-affinity Mn2+ site in apo-photosystem II, which is the initial site of photoactivation of the Mn cluster, was determined by PELDOR.
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