Hyponitrite Reductase in Neurospora

Abstract

THERE is much uncertainty in regard to the pathway of nitrite reduction in micro-organisms and in higher plants. Although nitrite and hydroxylamine reductases have been found in some bacteria¹, Neurospora and in higher plants^2,3, the immediate reduction product of nitrite has not been identified. Several workers⁴ have suggested that hyponitrite is the intermediate, but Taniguchi et al.¹ have shown that hyponitrite was not reduced by crude extracts of a bacterium tolerant to halogens containing all the enzyme systems for the successive reduction of nitrate to ammonia. In the denitrification process, too, hyponitrite as well as nitramide have been postulated to be intermediates in nitrite reduction. Lees⁵, however, found that hyponitrite was not utilized by washed cells of Nitrosomonas.