Cross pathway regulation: Tryptophan mediated control of histidine and arginine biosynthetic enzymes in Neurospora crassa

Abstract

In N. crassa, the starvation of tryptophan mutants for tryptophan resulted in the derepression of tryptophan, histidine, and arginine biosynthetic enzymes. This tryptophan mediated depression of histidine and arginine biosynthetic enzymes occurred despite the fact that tryptophan starved cells had a higher intracellular concentration of histidine and arginine than did nonstarved cells.