Phytodetoxification of TNT by transgenic plants expressing a bacterial nitroreductase

There is major international concern over the wide-scale contamination of s oil and associated ground water by persistent explosives residues. 2,4,6-Tr initrotoluene (TNT) is one of the most recalcitrant and toxic of all the mi litary explosives. The lack of affordable and effective cleanup technologie s for explosives contamination requires the development of better processes . Significant effort has recently been directed toward the use of plants to extract and detoxify TNT. To explore the possibility of overcoming the hig h phytotoxic effects of TNT, we expressed bacterial nitroreductase in tobac co plants. Nitroreductase catalyzes the reduction of TNT to hydroxyaminodin itrotoluene (HADNT), which is subsequently reduced to aminodinitrotoluene d erivatives (ADNTs). Transgenic plants expressing nitroreductase show a stri king increase in ability to tolerate, take up, and detoxify TNT. Our work s uggests that expression of nitroreductase (NR) in plants suitable for phyto remediation could facilitate the effective cleanup of sites contaminated wi th high levels of explosives.