Cadmium induced MTs synthesis via oxidative stress in yeast Saccharomyces cerevisiae

Yeast, Saccharomyces cerevisiae, exposed to CdCl2 for 17 h was analysed with reference to survival, MTs and oxidative stress biomarkers. An enhanced accumulation of MDA and the increased activities of SOD and GPx in the Cd-treated yeasts under aerobic condition indicated CdCl2-caused oxidative stress in S. cerevisiae. MTs were significantly induced by CdCl2 under aerobic condition and the induced MTs contents were positively correlated with the accumulation of MDA in this study. However, MTs induction can be prominently inhibited by coincubation with NAC or anaerobic culture via eliminating ROS. This oxidative stress reduction was reflected by the decreases in MDA level and SOD and GPx activities. The results suggest that MTs inductive activity of cadmium in yeast cells was mediated by oxidative stress. In addition, increase of MTs contents was observed in cells untreated with CdCl2 under anaerobic conditions or coincubation with NAC, suggesting MTs are also susceptive to reductive stress. (Mol Cell Biochem xxx: 139–145, 2005)