Alkaline phosphatase inactivation by mixed function oxidation systems.
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.
Mordente
A
A
Istituto di Chimica Biologica, Università Cattolica del S. Cuore Facoltà di Medicina e Chirurgia Agostino Gemelli, Roma, Italy.
Miggiano
G A
GA
Martorana
G E
GE
Meucci
E
E
Santini
S A
SA
Castelli
A
A
D000469:Alkaline Phosphatase / Q000037:antagonists & inhibitors*; D000975:Antioxidants / Q000494:pharmacology; D001205:Ascorbic Acid / Q000378:metabolism / Q000494:pharmacology; D002374:Catalase / Q000494:pharmacology; D002413:Cations, Divalent; D003300:Copper / Q000494:pharmacology; D005290:Ferric Compounds / Q000494:pharmacology; D005296:Ferrous Compounds / Q000494:pharmacology; D005609:Free Radicals; D005978:Glutathione / Q000494:pharmacology; D006861:Hydrogen Peroxide / Q000494:pharmacology; D006878:Hydroxides / Q000494:pharmacology; D017665:Hydroxyl Radical; D007700:Kinetics; D008623:Mercaptoethanol / Q000494:pharmacology; D008670:Metals / Q000494:pharmacology; D006899:Mixed Function Oxygenases / Q000378:metabolism*; D010084:Oxidation-Reduction; D009195:Peroxidase / Q000494:pharmacology; D013482:Superoxide Dismutase / Q000494:pharmacology; D013890:Thiourea / Q000494:pharmacology; D014527:Uric Acid / Q000494:pharmacology; D014810:Vitamin E / Q000494:pharmacology; D014969:Xanthine Oxidase / Q000494:pharmacology
D000975:Antioxidants; D002413:Cations, Divalent; D005290:Ferric Compounds; D005296:Ferrous Compounds; D005609:Free Radicals; D006878:Hydroxides; D008670:Metals; D014810:Vitamin E; D014527:Uric Acid; D017665:Hydroxyl Radical; D008623:Mercaptoethanol; D003300:Copper; D006861:Hydrogen Peroxide; D006899:Mixed Function Oxygenases; D002374:Catalase; D009195:Peroxidase; D013482:Superoxide Dismutase; D014969:Xanthine Oxidase; D000469:Alkaline Phosphatase; D005978:Glutathione; D013890:Thiourea; D001205:Ascorbic Acid