Naumenko, E. A.Naumov, A. V.Suvorova, E. S.Gerlach, RobinZiganshin, Ayrat M.Lozhkin, A. P.Silkin, N. I.Naumova, R. P.2017-07-072017-07-072008-04Naumenko EA, Naumova AV, Suvorova ES, Gerlach R, Ziganshin AM, Lozhkin AP, Silkin NI, Naumova RP, "Participation of oxygen in the bacterial transformation of 2,4,6-trinitrotoluene," Biochemistry (Moscow) 73(4):463-469 (2008)0006-2979https://scholarworks.montana.edu/handle/1/13192The exposure of Bacillus cereus ZS18 cell suspensions to 2,4,6-trinitrotoluene (TNT) in the absence of other oxidizable substrates increases oxygen uptake, exceeding the basal level of respiration of the bacterium 1.5- and 2-fold with 50 and 100 mg/liter of TNT, respectively. The interaction of both living and to less extent dead bacterial cells with TNT results in the accumulation of superoxide anion (O2-) in the extracellular medium, which was revealed by the EPR spectroscopy. The accumulation of O2- decreased by 50-70% in the presence of Cu,Zn-superoxide dismutase of animal origin. In the presence of living bacterial cells, the level of TNT decreased progressively, yielding hydroxylaminodinitrotoluenes together with O2-. In the presence of heat-killed cells, a moderate decrease in TNT was observed, and the appearance of O2- was not accompanied by the production of any detectable TNT metabolites. Chelating agents inhibited the transformation of TNT and decreased the formation of O2-. The demonstrated generation of O2- during the interaction of TNT with K4[Fe(CN)6] together with the observed effects of chelating agents suggest the participation of iron in the one-electron reduction of TNT and the functioning of an extracellular redox cycle with the involvement of molecular oxygen.Article