REDOX IMBALANCE AT THE START OF EACH MORPHOGENETIC STEP OF NEUROSPORA-CRASSA CONIDIATION

The conidiation process of Neurospora crassa is characterized by three morphogenetic steps: hyphal adhesion, aerial hyphal formation, and pr oduction of conidia. Total protein oxidation and specific enzyme oxida tion coincided with an increased oxygen-dependent chemiluminescence an d indicated the occurrence of a hyperoxidant state at the onset of all three morphogenetic steps. Oxidation of NAD(P)H and excretion of glut athione disulfide was detected at the start of hyphae adhesion. Here w e show that NAD(P)H and glutathione redox imbalance also occurred at t he beginning of aerial hyphal growth and just before formation of coni dia in the isolated cell structures. An increased loss and oxidation o f NAD(P)(H) and glutathione were detected with each morphogenetic tran sition. These results give further support to our proposal that a hype roxidant state develops at the start of each of the three morphogeneti c processes during N. crassa conidiation. (C) 1995 Academic Press, Inc .