The Effect of Molybdenum Deficiency on the Catalase and Peroxidase Content of Neurospora crassa

Abstract

Catalase and peroxidase were markedly decreased in quantity in molybdenum-deficient felts of N. crassa. Addition of Mo aseptically and in vivo restored the activities of the 2 enzymes. Infiltration of hydrogen peroxide to growing felts, deficient in Mo, after 3 days growth, resulted in a partial reconstitution of catalase to 18% and peroxidase to 50% of the control levels after a further 2 days growth but the weight of mycelium remained unchanged. The purified enzymes were not activated by Mo. The effect of Mo deficiency is probably indirect, resulting from a decrease in the activity of molybdenum-dependent flavoproteins which produce hydrogen peroxide, the common substrate for catalase and peroxidase.