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Updated: Jun 30, 2026

Synthesis and Evaluation of a Ruthenium-based Mitochondrial Calcium Uptake Inhibitor
Published on: October 26, 2017
Disorganization of the Mn4Ca complex of photosystem II by ruthenium red: a thermoluminescence study
Alain Gauthier1, Robert Carpentier
1Groupe de Recherche en Biologie Végétale (GRBV), Université du Québec à Trois-Rivières, C.P. 500 Trois-Rivières, Québec, Canada.
Abstract:
Ruthenium red (RR) is known to be an inhibitor that binds to Ca2+ sites. It releases Ca2+ and Cl(-) together with the extrinsic polypeptide of 17 kDa associated with the oxygen evolving complex of photosystem II. In this work we used thermoluminescence to study S2/3QB(-) and S2QA(-) charge recombination. It is shown that RR produced a deeper inhibition of oxygen evolution compared with the effect of extrinsic polypeptide or Ca2+/Cl(-) depletion. Even though Mn is not released, the Mn cluster is disorganized by RR and the S1-->S2 transition is inhibited.
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