Analysis of the oxidative stress response of Penicillium chrysogenum to menadione

The intracellular superoxide and glutathione disulphide concentrations incr eased in Penicillium chrysogeum treated with 50, 250 or 500 mu M menadione (MQ). A significant increase in the intracellular peroxide concentration wa s also observed when mycelia were exposed to 250 or 500 mu M MQ. The specif ic activity of Cu,Zn and Mn superoxide dismutases, glutathione reductase an d glutathione S-transferase as well as the glutathione producing activity i ncreased in the presence of MQ while glutathione peroxidase and gamma-gluta myltranspeptidase were only induced by high intracellular peroxide levels. The glucose-6-phosphate dehydrogenase and catalase activities did not respo nd to the oxidative stress caused by MQ.