Oxidative stress sensitivity inDebaryomyces hansenii

Abstract

Debaryomyces hansenii is an osmotolerant and halotolerant yeast of increasing interest for fundamental and applied research. In this work, we have performed a first study on the effect of oxidative stress on the performance of this yeast. We have used Saccharomyces cerevisiae as a well-known reference yeast. We show that D. hansenii is much more susceptible than S. cerevisiae to cadmium chloride, hydrogen peroxide or 1,4-dithiothreitol. These substances induced the formation of reactive oxygen species (ROS) in both yeasts, the amounts measured being significantly higher in the case of D. hansenii. We also show that NaCl exerted a protective effect against oxidative stress in Debaryomyces, but that this was not the case in Saccharomyces because sodium protected that yeast only when toxicity was induced with cadmium. On the basis of the present results, we raised the hypothesis that the sensitivity to oxidative stress in D. hansenii is related to the high amounts of ROS formed in that yeast and that observations such as low glutathione amounts, low basal superoxide dismutase and peroxidase activities, decrease in ATP levels produced in the presence of ROS inducers and high cadmium accumulation are determinants directly or indirectly involved in the sensitivity process.

Exogenous Calcium Improves Viability of Biocontrol Yeasts Under Heat Stress by Reducing ROS Accumulation and Oxidative Damage of Cellular Protein

“…In this study, we found that the activities of SOD and POD of D. hansenii increased markedly when treated with exogenous calcium (Table 1). Similar results have been reported by Navarrete et al [17], who found that NaCl exerted a protective effect against oxidative stress in D. hansenii. Fig.…”

Salt and oxidative stress tolerance inDebaryomyces hanseniiandDebaryomyces fabryi

“…Recent reports have related salt and oxidative stress tolerance in D. hansenii (Navarrete et al ., ; Calderon‐Torres et al ., ). To further investigate the phenotypic differences among the strains in study, tolerance to oxidative stress was checked by exposing the cells to hydrogen peroxide and analyzing their survival along time (Fig.…”

Monovalent cations regulate expression and activity of the Hak1 potassium transporter in Debaryomyces hansenii

“…hansenii is a salt tolerant yeast that somehow uses sodium to protect itself against some abiotic stress factors (Almagro et al, 2000;Papouskova and Sychrova, 2007;Navarrete et al, 2009) and that withstands high levels of intracellular sodium. In fact it has been reported that, for example, in media with low K + , Na + is able to substitute for K + , restoring the specific growth rate (Prista et al, 1997).…”