Glutathione reductase from Oryza sativa increases acquired tolerance to abiotic stresses in a genetically modified Saccharomyces cerevisiae strain.

Abstract

Glutathione reductase (GR, E.C. 1.6.4.2) is an important enzyme that reduces glutathione disulfide (GSSG) to a sulfydryl form (GSH) in the presence of an NADPH-dependent system. This is a critical antioxidant mechanism. Owing to the significance of GR, this enzyme has been examined in a number of animals, plants, and microbes. We performed a study to evaluate the molecular properties of GR (OsGR) from rice (Oryza sativa). To determine whether heterologous expression of OsGR can reduce the deleterious effects of unfavorable abiotic conditions, we constructed a transgenic Saccharomyces cerevisiae strain expressing the GR gene cloned into the yeast expression vector p426GPD. OsGR expression was confirmed by a semiquantitative reverse transcriptase polymerase chain reaction (semiquantitative RT-PCR) assay, Western-blotting, and a test for enzyme activity. OsGR expression increased the ability of the yeast cells to adapt and recover from H2O2-induced oxidative stress and various stimuli including heat shock and exposure to menadione, heavy metals (iron, zinc, copper, and cadmium), sodium dodecyl sulfate (SDS), ethanol, and sulfuric acid. However, augmented OsGR expression did not affect the yeast fermentation capacity owing to reduction of OsGR by multiple factors produced during the fermentation process. These results suggest that ectopic OsGR expression conferred acquired tolerance by improving cellular homeostasis and resistance against different stresses in the genetically modified yeast strain, but did not affect fermentation ability.

• Authors: Il-Sup Kim, Young-Saeng Kim, Ho-Sung Yoon
• Journal: Journal of microbiology and biotechnology (J Microbiol Biotechnol) Vol. 22 Issue 11 Pg. 1557-67 (Nov 2012) ISSN: 1738-8872 [Electronic] Korea (South)
• PMID: 23124348 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• Plant Proteins
• Hydrogen Peroxide
• Glutathione Reductase

Topics

• Gene Expression
• Genetic Engineering
• Glutathione Reductase (genetics, metabolism)
• Hydrogen Peroxide (metabolism)
• Oryza (enzymology)
• Oxidative Stress
• Plant Proteins (genetics, metabolism)
• Saccharomyces cerevisiae (genetics, metabolism)