OYE Flavoprotein Reductases Initiate the Condensation of TNT-Derived Intermediates to Secondary Diarylamines and Nitrite
Rolf-Michael Wittich
Alí Haïdour
Pieter Van Dillewijn
Juan-Luis Ramos
10.1021/es071449w.s001
https://acs.figshare.com/articles/journal_contribution/OYE_Flavoprotein_Reductases_Initiate_the_Condensation_of_TNT_Derived_Intermediates_to_Secondary_Diarylamines_and_Nitrite/2960056
Polynitroaromatic explosives such as 2,4,6-trinitrophenol (picric acid) and 2,4,6-trinitrotoluene (TNT) are toxic and recalcitrant environmental pollutants. They persist in the environment due to the highly inactivated π system of their aromatic rings, which are inaccessible to dioxygenases that normally initiate the bacterial aerobic catabolism of (nitro-) aromatic compounds. Aside from reductive transformation of nitro side groups to hydroxylamines, trinitroarenes are prone to aromatic ring reductions by some flavin reductases to yield Meisenheimer mono and dihydride complexes. Here we show that the simultaneous accumulation of Meisenheimer complexes and aromatic hydroxylamines derived from TNT gives rise to the condensation of both types of reactive intermediates to secondary diarylamines and nitrite as the end-products of this environmentally relevant reaction sequence. As a consequence, overall mass balances of aerobic biotransformations of TNT become possible for the first time. In our study, the process of TNT activation was enzymatically initiated by the xenobiotic reductase B (XenB)-like flavin reductase of Pseudomonas putida JLR11 and then completed chemically by autodimerization. The structures of the formed end products were unequivocally elucidated by NMR.
2008-02-01 00:00:00
hydroxylamine
OYE Flavoprotein Reductases Initiate
reaction sequence
picric acid
dihydride complexes
NitritePolynitroaromatic explosives
reactive intermediates
Pseudomonas putida JLR 11
ring reductions
π system
xenobiotic reductase B
flavin reductases
NMR
nitro side groups
reductive transformation
end products
Meisenheimer complexes
Secondary Diarylamines
TNT activation
mass balances