Inhibition of Metal-Catalyzed Oxidation Systems by a Yeast Protector Protein in the Presence of Thioredoxin

doi:10.1006/bbrc.1994.1662

Biochemical and Biophysical Research Communications

Volume 201, Issue 1, 30 May 1994, Pages 8-15

https://doi.org/10.1006/bbrc.1994.1662 Get rights and content

Abstract

A protector protein from Saccharomyces cerevisiae specifically prevents the inactivation of enzymes caused by a thiol/Fe³⁺/O₂ metal-catalyzed oxidation system but not by an ascorbate/Fe³⁺/O₂ system. Ascorbate/Fe³⁺/O₂-mediated damage of enzymes could be prevented by the protector protein only in the presence of reduced thiol. We demonstrate that two proteins from yeast, thioredoxin plus another protein having properties similar to that expected to thioredoxin reductase, when presented with NADPH and the yeast protector protein prevented inactivation of E. coli glutamine synthetase by the ascorbate/Fe³⁺/O₂, system. This system also removes hydrogen peroxide effectively. We also demonstrate evidence suggesting that the NADPH-dependent thioredoxin system reactivates protector protein by reversible disulfide-dithiols exchange.

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Citation Excerpt :
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Regular ArticleInhibition of Metal-Catalyzed Oxidation Systems by a Yeast Protector Protein in the Presence of Thioredoxin

Abstract

Regular Article
Inhibition of Metal-Catalyzed Oxidation Systems by a Yeast Protector Protein in the Presence of Thioredoxin