N-Acetyl cysteine improves cellular growth in respiratory-deficient yeast

Abstract

Background: Reactive oxygen species (ROS) is a main factor that alters cellular physiology and functionality. Many strategies are used in order to control excessive oxidative stress. One strategy includes the use of antioxidants like N-acetyl cysteine (NAC). The aim of this study was to compare the effect of this antioxidant on ROS production and cellular growth of a wild-type and a respiratory-deficient Saccharomyces cerevisiae strain. Methods: Using a simple system such as yeast allows oxidative stress investigations on which numerous factors are more manageable or circumscribed than in a higher organism. We grew cells in a complex medium and incubated them during 72 h. Later, cellular viability and ROS production was evaluated. ROS level was estimated by use of fluorescence signal with 2′,7′-dichlorofluorescein diacetate (DCFH-DA). Results: As it is found in the present work, a reducing environment exerted by NAC presence during incubation of the cells allows a respiratory-deficient Saccharomyces cerevisiae strain to improve its cellular growth. Conclusions: It seems likely that the energy production or the phenotype which characterizes a deficient strain is incapable of palliating ROS growth inhibition while NAC helps to overcome this limitation.