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PubMed · 3103684

Hydrogen peroxide as an alternate substrate for the oxygen-evolving complex.

W D Frasch·R Mei
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Abstract

Photosystem II reaction centers evolve O2 in the dark when H2O2 is added as a substrate. Although some of this activity can be attributed to catalase, as much as 75% of the activity was not affected by the addition of 1 mM KCN. Several lines of evidence demonstrate that this KCN-insensitive O2 evolution from H2O2 in the dark is catalyzed by the cycling of S states in the oxygen-evolving complex including: inactivation of H2O2-mediated O2 evolution by Ca/EDTA washing; susceptibility of the activity to inhibition by amines like ammonia and Tris; inhibition by CCCP which is known to accelerate the rate of deactivation of the S2 state and; a direct dependence of the rate of O2 evolution on the presence of calcium and chloride.

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CalciumCarbonyl Cyanide m-Chlorophenyl HydrazoneChloridesChlorophyllEdetic AcidHydrogen PeroxideLight-Harvesting Protein ComplexesManganeseOxygenPhotosynthetic Reaction Center Complex ProteinsPhotosystem II Protein ComplexPlant ProteinsPotassium CyanideJournal ArticleResearch Support, U.S. Gov't, Non-P.H.S.Research Support, U.S. Gov't, P.H.S.

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W D Frasch, R Mei. 1987-03-25. Hydrogen peroxide as an alternate substrate for the oxygen-evolving complex.. https://doi.org/10.1016/0005-2728(87)90077-6

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