Oxidative stress responses of the yeastSaccharomyces cerevisiae

Abstract

All aerobically growing organisms suffer exposure to oxidative stress, caused by partially reduced forms of molecular oxygen, known as reactive oxygen species (ROS). These are highly reactive and capable of damaging cellular constituents such as DNA, lipids and proteins. Consequently, cells from many different organisms have evolved mechanisms to protect their components against ROS. This review concentrates on the oxidant defence systems of the budding yeast Saccharomyces cerevisiae , which appears to have a number of inducible adaptive stress responses to oxidants, such as H2 O2 , superoxide anion and lipid peroxidation products. The oxidative stress responses appear to be regulated, at least in part, at the level of transcription and there is considerable overlap between them and many diverse stress responses, allowing the yeast cell to integrate its response towards environmental stress. © 1998 John Wiley & Sons, Ltd.

Melatonin Reduces Oxidative Stress Damage Induced by Hydrogen Peroxide in Saccharomyces cerevisiae

“…Yeast cells are constantly monitoring ROS concentrations in an attempt to maintain them at a basal level by invoking antioxidant defense mechanisms, which are grouped into enzymatic and non-enzymatic systems that operate at different levels (Jamieson, 1998; Moradas-Ferreira and Costa, 2000; Costa and Moradas-Ferreira, 2001). Enzymatic systems, which include catalase, superoxide dismutase, and glutathione peroxidase, are primary defenses that function to neutralize ROS.…”

“…Enzymatic systems, which include catalase, superoxide dismutase, and glutathione peroxidase, are primary defenses that function to neutralize ROS. In contrast, non-enzymatic systems, such as the glutathione, glutaredoxin family or thioredoxins, are secondary defenses that repair or remove the products of oxidative damage (Jamieson, 1998). To eliminate ROS, cells need to be equipped with regulatory molecules that rapidly sense and respond to oxidative stress.…”

“…In yeast, the parallel glutathione/glutaredoxin and thioredoxins pathways (essential under aerobic and anaerobic conditions) (Herrero et al, 2008) make a large contribution to protection against oxidative damage by reacting with ROS (Auchère et al, 2008). Glutathione (GSH) is well known as the main and most abundant endogenous antioxidant in cells (Izawa et al, 1995; Moradas-Ferreira et al, 1996; Jamieson, 1998). GSH reacts with ROS, donating an electron to neutralize them and becoming reactive itself, resulting in the formation of GSSG, the oxidized state, through the combination of two reactive forms of GSH.…”

“…Catalase A and catalase T decompose H 2 O 2 to oxygen and water in the peroxisome and the cytosol, respectively. Superoxide dismutases catalyze the conversion of superoxide anion to oxygen and H 2 O 2 in the cytoplasm (Cu/ZnSOD) and in mitochondria (Mn/ZnSOD) (Jamieson, 1998; Costa and Moradas-Ferreira, 2001; Auchère et al, 2008). Most of these antioxidant mechanisms are considered universal in living organisms, and regulating expression of the genes involved as well as enzyme activity is crucial for cell survival.…”

“…To accomplish this, we evaluated ROS production, intracellular glutathione levels (GSH/GSSG), and expression of certain genes involved in the oxidative stress response in a commercial wine yeast strain in both the presence and absence of MEL (5 μM) and oxidative stress (addition of 2 mM H 2 O 2 ). Furthermore, as several studies have demonstrated that yeast cells in the stationary phase exhibit a significant degree of resistance toward oxidants (Jamieson, 1998; Gibson et al, 2008), the effect of MEL was evaluated in both the exponential and stationary phases.…”