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PubMed · 2996545

Full, reversible copper removal from ascorbate oxidase.

I Savini·L Morpurgo·L Avigliano
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Abstract

Anaerobic treatment with cyanide of reduced ascorbate oxidase causes total depletion of copper. No significant amount of the metal is reincorporated when the apo-enzyme is incubated with cupric ions, but it is upon incubation with a stoichiometric amount (eight mol per mol of native enzyme) of a Cu(I) complex stable in air [Cu(I)(thiourea)3]Cl. The yield in reconstituted protein is higher under anaerobic conditions (85-90%) than in air (70-75%). By treatment with less than stoichiometric amounts of [Cu(I)(thiourea)3]Cl the apo-protein binds copper preferentially at the blue copper site. As a consequence the recovery of enzymatic activity is percentually lower than copper reincorporation.

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ApoenzymesApoproteinsAscorbate OxidaseChemical PhenomenaChemistryCopperCyanidesElectron Spin Resonance SpectroscopyOrganometallic CompoundsOxidoreductasesOxygenSpectrophotometryThioureaJournal Article

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BibTeXRIS

I Savini, L Morpurgo, L Avigliano. 1985-09-30. Full, reversible copper removal from ascorbate oxidase.. https://doi.org/10.1016/0006-291x(85)90225-6

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