Enzymatic Reduction of Aromatic Nitro, Nitroso and Hydroxyl amino Compounds

Abstract

Abstract 1) A cell-free enzyme preparation of a halotolerant bacterium activates aromatic nitroso and hydroxylamino compounds as well as nitro compounds and accelerates their reduction by hydrogen donator systems. 2) The enzymatic reduction of nitroso and hydroxylamino was more strongly inhibited by cyanide and azide than that of nitro. 3) Methylene blue, which can not be used as an intermediary hydrogen carrier in the case of nitro reduction, can be used in the cases of nitroso and hydroxylamino reduction. 4) From these facts, we have been led to the consideration that there exist special enzymes such as nitroso-reductase and hydroxylamino-reductase besides nitro-reductase. 5) Azoxy, azo, and hydrazo compound cannot be reduced by the enzyme preparation. 6) From the studies of reaction velocity and paper chromatography of the intermediates and the end products, we proposed a scheme concerning the enzymatic reduction of nitro to amino, namely: (Remark: Graphics omitted.)