ELIMINATION OF NITRITE FROM THE EXPLOSIVE 2,4,6-TRINITROPHENYLMETHYLNITRAMINE (TETRYL) CATALYZED BY FERREDOXIN NADP OXIDOREDUCTASE FROM SPINACH

Nitroreductase enzymes generally catalyze the reduction of nitroaromat ic compounds to the corresponding amines. In contrast, ferredoxin NADP oxidoreductase (FNR), glutathione reductase, xanthine oxidase, and cy tochrome c reductase catalyze the NADPH dependent elimination of the n itramine nitro group from 2,4,6-trinitrophenylmethylnitramine to form N-methylpicramide (NMP). Nitrite elimination was inhibited under aerob ic conditions. Our results suggest that under aerobic conditions, tetr yl is enzymatically reduced to the nitroanion radical which is then in volved in the reduction of molecular oxygen. Under anaerobic condition s, the radical is reduced to NMP and nitrite is eliminated. (C) 1996 A cademic Press, Inc.