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PubMed · 8557101

Ascorbate is the natural substrate for plant peroxidases.

H Mehlhorn·M Lelandais·H G Korth·C H Foyer
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Abstract

Ascorbate-dependent detoxification of hydrogen peroxide by guaiacol-type peroxidases is increased considerably in the presence of 3,4-dihydroxyphenolic compounds, suggesting that ascorbate is the natural substrate for many types of peroxidase in situ and not just the ascorbate-specific peroxidases. The ascorbate-dependent destruction of hydrogen peroxide in the more acidic cellular compartments such as the vacuole may be an important function of such non-specific peroxidases. The stress-induced production of phenolic compounds would render the guaiacol peroxidases in other less acidic-cellular sites effective as ascorbate-dependent H2O2-detoxifying enzymes.

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AntibodiesAscorbate PeroxidasesAscorbic AcidCaffeic AcidsChlorogenic AcidElectron Spin Resonance SpectroscopyElectrophoresis, Polyacrylamide GelHorseradish PeroxidaseHydrogen PeroxideIsoelectric FocusingKineticsPeroxidasesPhenolsPlantsSubstrate SpecificityTeaJournal ArticleResearch Support, Non-U.S. Gov't

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H Mehlhorn, M Lelandais, H G Korth, C H Foyer. 1996-01-15. Ascorbate is the natural substrate for plant peroxidases.. https://doi.org/10.1016/0014-5793(95)01448-9

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