Involvement of glutathione peroxidase 1 in growth and peroxisome formation in Saccharomyces cerevisiae in oleic acid medium

Saccharomyces cerevisiae is able to use some fatty acids, such as oleic acid, as a sole source of carbon. beta-oxidation, which occurs in a single membrane-enveloped organelle or peroxisome, is responsible for the assimilation of fatty acids. In S. cerevisiae, beta-oxidation occurs only in peroxisomes, and H2O2 is generated during this fatty acid-metabolizing pathway. S. cerevisiae has three GPX genes (GPX1. GPX2, and GPX3) encoding atypical 2-Cys peroxiredoxins. Here we show that expression of GPX1 was induced in medium containing oleic acid as a carbon source in an Msn2/Msn4-dependent manner. We found that Gpx1 was located in the peroxisomal matrix. The peroxisomal Gpx1 showed peroxidase activity using thioredoxin or glutathione as a reducing power. Peroxisome biogenesis was induced when cells were cultured with oleic acid. Peroxisome biogenesis was impaired in gpx1 Delta cells, and subsequently, the growth of gpx1 Delta, cells was lowered in oleic acid-containing medium. Gpx1 contains six cysteine residues. Of the cysteine-substituted mutants of Gpx1, Gpx1(c36S) was not able to restore growth and peroxisome formation in oleic acid-containing medium, therefore, redox regulation of Gpxl seems to be involved in the mechanism of peroxisome formation. (C) 2012 Elsevier B.V. All rights reserved.