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Alkaline phosphatase inactivation by mixed function oxidation systems.

A Mordente·G A Miggiano·G E Martorana·E Meucci·S A Santini·A Castelli
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Abstract

Alkaline phosphatase is inactivated by mixed function oxidation systems. OH. radicals, generated via an ascorbate-modified Haber-Weiss cycle or a Fenton-type reaction, seem to be responsible for the protein oxidative damage. Experiments with hydroxyl radical scavengers, enzyme substrates, products, and metal cofactors suggest that a "site-specific" radical attack takes place at or near the active center. Vitamin E fails to protect alkaline phosphatase; uric acid, instead, is particularly effective in shielding the protein against covalent modifications.

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Alkaline PhosphataseAntioxidantsAscorbic AcidCatalaseCations, DivalentCopperFerric CompoundsFerrous CompoundsFree RadicalsGlutathioneHydrogen PeroxideHydroxidesHydroxyl RadicalKineticsMercaptoethanolMetalsMixed Function OxygenasesOxidation-ReductionPeroxidaseSuperoxide DismutaseThioureaUric AcidVitamin EXanthine OxidaseComparative StudyJournal Article

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A Mordente, G A Miggiano, G E Martorana, E Meucci, S A Santini, A Castelli. 1987. Alkaline phosphatase inactivation by mixed function oxidation systems.. https://doi.org/10.1016/0003-9861(87)90334-1

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